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Energy Strategy Reviews (Jul 2020)

Assessment of the French nuclear energy system – A case study

• Carlos E. Velasquez,
• Fidéllis B.G. L. e Estanislau,
• Antonella L. Costa,
• Claubia Pereira

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The country with the highest nuclear power contribution to its energy matrix is France with 72.28%. The French nuclear history reveals that they trust in reprocessing option since an early stage of the nuclear power plants. Therefore, this work is devoted to studying the two options of a fuel cycle, i.e., Open Fuel Cycle (OFC) and Closed Fuel Cycle (CFC) for this country and the economics of each scenario. The assessment begins using the MESSAGE, since the first official registration by the International Atomic Energy Agency (IAEA), which is in 1970 and tries to follow the model until 2016. After that, the MESSAGE adjusts the energy planning to fit best until 2034 remaining the nuclear activity in this country. The results show the best reactor option to supply 50000 MWyr until 2034 using the two fuel cycle models. Finally, it is shown the amount of resources needed to maintain the nuclear power industry in France and justify the French option of the fuel cycle based on the economic results. The results show the use of nuclear resources taking advantage of a closed fuel cycle. The idea is to show the sustainability of a closed fuel cycle, applying this methodology to countries in nuclear development with a different scenario.

• Nuclear energy system
• Nuclear fuel cycle options

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• 06 September 2022

Daily briefing: France’s nuclear industry faces uncertainty

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A crate with Japanese text on it was among the plastic debris collected by researchers studying the North Pacific garbage patch. Credit: The Ocean Cleanup

Fishers are feeding the great garbage patch

Fishing gear makes up most of the large plastic debris in the ‘North Pacific garbage patch’ , an area of the ocean where currents converge and an estimated 80,000 tonnes of plastic have accumulated. One-third of the identified things in a survey of more than 6,000 floating items came from Japan — possibly in part because of the tsunami that hit the country in 2011. The finding suggests that rubbish expelled from rivers — thought to be the source of most ocean plastic — ends up in coastal areas, not the garbage patch. “What this paper and other investigations have shown is that there is really one sector — fishing — responsible for this plastic,” says ocean researcher Lisa Erdle.

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Nature | 12 min read

France’s nuclear industry faces uncertainty

No other country produces as much nuclear power per capita as France, and its leadership in the field has long been a source of national pride. The need to phase out fossil fuels has even tempted some long-time opponents to grudgingly support nuclear energy. And it has taken on fresh saliency as global energy prices spike in response to Russia’s invasion of Ukraine. But half of France’s nuclear reactors are now offline because they need maintenance or because the ongoing heatwave has curtailed the supply of water needed to cool the reactors. And government support for the technology has run hot and cold.

Nature | 8 min read

This article is part of Nature Spotlight: Science in France , an editorially independent supplement.

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The US government announced last month that research articles and most underlying data generated with federal funds should be made publicly available without cost. But that policy, and ones like it, will not achieve the goal of making data more accessible, because most of those data will be unfindable. Policies and infrastructure are needed to organize metadata , says biomedical informaticist Mark Musen. “Because the metadata are so ad hoc, automated searches fail, and investigators waste enormous amounts of time,” he writes. “Metadata for data sets must stand on their own.”

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• France’s Nuclear Power: Current Difficulties, New Policies, and 100% Renationalization
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France’s Nuclear Power Current Difficulties, New Policies, and 100% Renationalization

Romain Zissler, Senior Researcher, Renewable Energy Institute

23 August 2022

in Japanese

Because of reliability failures France’s nuclear power is currently underperforming. Despite this problem the French government remains supportive of nuclear power as demonstrated by the new policies announced by President Emmanuel Macron in favor of this technology on February 10, 2022. Nevertheless, implementing these policies will be challenging and require a strong business operation structure in Électricité de France (EDF). EDF is France’s former national vertically integrated monopoly for electricity and the world’s #1 nuclear power company – the cornerstone of the French power system. On July 6, 2022, French Prime Minister Elisabeth Borne confirmed the State’s intention to control 100% of EDF (instead of 84%). 1 In the status quo, because of EDF’s economic fragility, resulting from issues related to nuclear power and detrimental political choices, the government does not consider the company capable of executing the planification of the country’s energy transition in the power sector – and notably its new nuclear power program. However, this 100% renationalization will certainly not make EDF and nuclear power suddenly thrive. Key actions will be needed regarding new financing schemes for nuclear power, end user price increases, and the reorganization of the company.

Current difficulties of nuclear power in France

In May 2022, EDF, the sole owner and operator of France’s 56 nuclear reactors (61 GW), projected electricity generation from nuclear power to significantly decrease to 280-300 TWh in 2022 and slightly rebound to 300-330 TWh in 2023. Both projections are well-below the country’s nuclear electricity generation peak of 430 TWh reached in 2005 – approximately -33% and -27%, respectively (Chart 1).

These negative projections are due to five factors currently affecting the output of French nuclear power. First, the “Grand Carénage”, a program focusing on safety upgrades and reactor lifetime extensions taking place from 2014 to 2025 – covering all existing reactors (average age of the fleet: 37 years), limits the availability of nuclear reactors. 2 Second, the COVID-19 pandemic has derailed the maintenance of reactors which is usually tuned like clockwork. Third, discoveries of cracks in pipes resulting from stress corrosion have led to the temporary shutdowns of 12 reactors of the most recent reactors for inspections. Fourth, unfavorably dry and warm weather conditions make it more complicated to cool reactors which must either reduce their output or temporary shut down. And fifth, the endless delays to start operating Flamanville-3 under construction since 2007 (completion originally planned for 2012 and now expected for 2023 at the earliest) results in a lack of 1,630 MW. As a result, since the beginning of 2022 more than half of French nuclear reactors have sometimes been unavailable leaving a deep hole in the French power system.

Finally, it may be noted that because of these underperformances, as well as the closures of almost all coal and oil power plants in France – which have not been sufficiently replaced by renewable energy, the country has become short on power supply capacity. Therefore, it now needs to rely on expensive imports. In this regard, on April 3, 2022, France’s power imports reached a new record of almost 14 GW (out of which more than half from Germany). 3 This is an upset for a country that is traditionally one of the world’s largest net exporters of electricity.

Despite difficulties France supportive of nuclear power again

On February 10, 2022, French President Macron announced his optimistic intention to extend the lifetime beyond 50 years of all the country’s existing reactors and to build 6 to 14 new large reactors as well as some small modular reactors (additional 25 GW by 2050). 4 The construction of the first new large reactor should start in 2028 with commissioning targeted in 2035. The first prototype of small modular reactor is forecasted for 2030. This announcement is the first positive set of objectives for the French nuclear industry in decades. It also has the merit to be clear after a period of very confusing energy policies between 2012 and 2021.

Two reasons may explain French policymakers’ recent change of heart in favor of nuclear power:

First, a report by the national transmission system operator Réseau de Transport d'Électricité (RTE), “Energy Futures 2050”, a long-term outlook of the French power system in the context of carbon neutrality by 2050 and beyond. The highlighted economic finding in this analysis is that: Under an electricity consumption scenario of reference, an electricity supply based on 50% nuclear power and 50% renewable energy would be the most cost-efficient electricity generation mix for the French power system in 2060. This scenario would require massive reactor lifetime extensions and constructing 14 new large reactors as well as some small modular reactors. It is hard not to see the similarities with President Macron’s announcement, which undoubtedly found a source of inspiration in RTE’s report. Earlier this year, Renewable Energy Institute already debated France’s new nuclear power plans in a column , questioning their feasibility because of the techno-economic difficulties they actually face [published on January 28, 2022].

Second, because of the ongoing energy crisis, energy security is under the spotlight again as during the oil shocks of the 1970s. At that time, France’s bold answer was to launch an unequaled nuclear power program to reduce the country’s exposure to fossil fuel imports. About a half century later the legacy of this program is significant with almost 70% of France’s electricity generation in 2021 still coming from nuclear power – by far the highest share in the world – thanks to the 56 reactors all connected to the grid between 1978 and 1999. So, what the French government sees in nuclear power is a good old remedy. To justify this stance, it considers that even if natural uranium is not mined in the country – and therefore needs to be imported (essentially from Niger, Kazakhstan, Uzbekistan, and Australia in the case of France), uranium is relatively easy to transport and store. However, this approach is controversial because it necessarily implies a contradictory continued dependance on foreign countries.

Finally, despite its recent underperformances, the domestic nuclear industry remains seen as one of the last few industrial strengths of France. This is not the case of the country’s renewable energy industry, which is not well-positioned: Neither in terms of access to critical minerals as inputs, nor in terms of manufacturing capacity of key technologies such as solar photovoltaic modules or wind turbines.

EDF’s 100% renationalization

Under these circumstances, the French government made the decision to turn back the clock by resuming EDF as a 100% nationalized entity. The following sub-sections answer the main questions about this renationalization.

The double objective of this strategical decision is (1) to retake full control of the country’s power sector energy transition & energy security and (2) put an end to the unsustainable situation of continuously frustrating minority shareholders with political decisions penalizing the company’s interests to protect customers. This is a clear signal the French government considers that in the status quo EDF is not capable of executing the planification of the country’s energy policy in the power sector which will require more low carbon electricity to decarbonize the transportation and the heating & cooling sectors. That is because of the economic difficulties the company is confronted with. Therefore, a major shake-up of EDF is needed and having a single decisionmaker should facilitate this process. The takeover bid on the 16% of the capital remaining to be acquired (i.e., shares and convertible bonds) is estimated at €9.7 billion. 5

In the first half of 2022 the company recorded an historical loss of €5.3 billion (Chart 2). There are two main reasons for EDF’s present economic difficulties: (1) worsening performances of the French nuclear industry, especially in the first half of this year (already presented in the first section of this column) – a terrible timing given the invasion of Ukraine by Russia causing severe turmoil on energy markets, and (2) two key harmful political choices by French governments; the “Regulated Access to Historic Nuclear Electricity” (abbreviated ARENH in French and used in hereinafter) and the tariff shield. Because neither the issues related to French nuclear power nor those related to French energy policies will be solved in 2022 H2, further deterioration of EDF’s net income may be expected by the end of this year.  

Moreover, in the past 15 years EDF’s net financial debt quasi tripled: From €16.3 billion at the end of 2007 to €42.8 billion at the end of June 2022. This is mainly because of EDF’s appetite for internationalization translating into costly acquisition of foreign companies (e.g., British Energy for €19 billion in 2009 and Edison for €5 billion in 2012), and because of major investments into two domestic major nuclear power projects: the “Grand Carénage” program (about €50 billion) and the country’s single reactor under construction Flamanville-3 (around €23 billion).

This level of indebtment limits EDF’s ability to finance France’s energy transition that requires massive investments in nuclear power, renewable energy, and power grids.    

Enacted in 2010 and into force since 2011 to theoretically encourage supply competition in the framework of France’s electricity system reform, the ARENH mechanism forces EDF to sell up to 100 TWh per year of its own nuclear power-based electricity to new entrants (e.g., ENGIE, Iberdrola, Vattenfall…) who could not have otherwise competed with EDF until the recent emergence of cost competitive renewable energy, enabling arbitrage among electricity generating technologies. The price of the ARENH should reflect the cost of existing nuclear power without a profit for EDF (i.e., sale at cost price). The original price was €40/MWh in 2011 and it marginally increased to €42/MWh from 2012. ARENH prices have often been competitive compared to power exchange prices, especially in 2021-2022 (Chart 3). Despite the heavy investments of the “Grand Carénage” program, the ARENH price remained at the same level for a decade resulting in prolonged underpayments of EDF’s assets (it will, at last, increase in 2023 – €49.5/MWh). 6

Moreover, because of the ongoing global energy crisis the French government implemented a tariff shield as a protective means in a tense social context marked by increasing energy poverty and the traumatic memory of the yellow vest protests (notably against the high cost of living) still haunting policymakers. Thus, despite skyrocketing wholesale electricity prices, the increases of EDF’s regulated electricity retail tariffs for residential and some professional customers are temporarily capped at only 4%. 7 Furthermore, EDF was forced to sell an extra 20 TWh to its competitors in the framework of the ARENH at a price of €46.2/MWh, and to buy 20 TWh from its competitors at a price of €257/MWh. 8 This decision was made to protect EDF’s competitors from a wave of bankruptcies and keep a parody of competition in the supply market alive. In reaction to this situation, on August 9, 2022, EDF filed a legal claim against the French government for indemnification for an amount estimated to date at €8.3 billion. 9 This absurd outcome demonstrates the failure of the French electricity system reform. Instead, diversifying cost competitive generating sources of electricity such as solar photovoltaic and wind should have been a priority. An area where, unfortunately, efforts have been insufficient until now – preventing true competition.

Finally, it may be noted that in 2020, because it was the country’s oldest nuclear power plant (two reactors of 880 MW each: both 42 years of commercial operations), Fessenheim was forced to permanently shut down. According to EDF, this decision was motivated by political opportunism to respect an outdated election promise which had no economic justification. On environmental and safety grounds, the cautious French nuclear safety authority was not opposed to the continuing the operations of the plant. The European Commission authorized a compensation (i.e., State aid) of more than €370 million to EDF for closing the plant. 10

As of mid-August 2022, it is challenging to predict the outcome of EDF’s 100% renationalization because of the lack of available details. Nevertheless, this strategic move will certainly not make EDF and nuclear power suddenly thrive. Moreover, key painful decisions will need to be adopted regarding end user tariffs and the reorganization of the company.

EDF’s 100% renationalization as well as the inclusion of nuclear power in the European Union Taxonomy are favorable developments for both the company and the technology. On the renationalization side, it is notably envisioned that fully owning the company will give French energy policymakers additional leverage when it comes to providing and accessing better financing conditions for nuclear power that is very capital-intensive with high financial costs (e.g., out of the €23 billion of Flamanville-3’s cost, approximately 20% are financing costs). 11 Yet, this will probably not be sufficient, and new financing schemes for nuclear power are likely to be necessary (e.g., contract for difference as in the United Kingdom).

Furthermore, given the enormous debt of the company and the need for massive investments, significant end user price increases are inevitable. The French government will be on a tight rope to strike the right balance between the interests of the company and those of the customers. This should start by finding solutions to stop sacrificing EDF on the altar of social peace. Pragmatism, pedagogy, and assistance to the most vulnerable customers will be critical. 

Finally, this renationalization is an opportunity to reorganize the company. Powerful unions have already expressed a strong opposition to the dismantling of the company into different completely separated businesses (i.e., “Hercules” restructuring deal: Nuclear / hydro / other renewable energy, distribution & supply). Even if this pathway is abandoned, French policymakers should not miss the chance to ambitiously rebalance the company’s activities. Possibly in favor of distribution and renewable energy two segments which performances – compared to the segment “France – Generation & Supply” (including nuclear power) – give satisfaction in terms of operating profit despite relatively low sales (Chart 4).

• 1 EDF, Capital Structure – updated July 25, 2022 (accessed August 4, 2022).
• 2 International Atomic Energy Agency, Power Reactor Information System: Countries, France – updated August 14, 2022 (accessed August 15, 2022).
• 3 RTE, eCO2mix - Key figures: Commercial Exchanges in France (accessed August 15, 2022).
• 4 French government, La nouvelle stratégie énergétique de la France – updated July 20, 2022 (accessed August 4, 2022) (in French).
• 5 Le Monde, Marjorie Cessac, EDF: l’État annonce une renationalisation à 9,7 milliards d’euros – July 19, 2022 (accessed August 4, 2022) (in French).
• 6 Les Échos, Julien Dupont-Calbo, Crise de l'énergie: le Parlement allège la facture pour EDF – August 2, 2022 (accessed August 4, 2022) (in French).
• 7 EDF, Exceptional measures announced by the French Government – January 13, 2022 (accessed August 4, 2022).
• 8 EDF, Publication of the decree and orders relating to the additional allocation of 20 TWh of ARENH volumes for 2022: update of the impact on the 2022 EBITDA outlook – March 14, 2022 (accessed August 4, 2022).
• 9 EDF, Legal claim concerning the allocation of additional electricity volumes at a regulated price for 2022 – August 9, 2022 (accessed August 15, 2022).
• 10 European Commission, Aides d'État: la Commission autorise l'indemnisation d'EDF pour la fermeture anticipée de la centrale nucléaire de Fessenheim en France – March 23, 2021 (accessed August 4, 2022) (in French).
• 11 Cour des Comptes, La Filière EPR (July 2020) (in French).
• 12 RTE, Rapport de Gestion 2021 (March 2022) (in French).

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An Overview of Nuclear Energy in France

Emanuel pinilla february 17, 2018, submitted as coursework for ph241 , stanford university, winter 2018, introduction.

France is amongst the top economic powers in the world and it has considerable political influence on the international level. With over 63 million inhabitants, France has the second largest population in the EU behind Germany. [1] Nuclear energy has long been a staple of Frances energy contribution and has led to significant interest in exploring the possibilities of nuclear energy. France has long been one of the most successful countries with respect to nuclear energy and this is exhibited by their merits. With 77% of the electricity in the country coming from nuclear power and accounting for 47% of all nuclear electricity in the EU, France has demonstrated the impact nuclear electricity may have. [1,2] France has built nuclear power plants throughout the country, including the Dampierre Plant seen in Fig. 1 and the Cattenom Plant seen in Fig. 2 - making the presence and success of nuclear energy very strong. Despite the success France has had with nuclear energy, safety concerns have risen over the past years as well as anti-nuclear protests which have led France to begin transitioning away from nuclear energy as the public has begun to change their stance on the idea of long term nuclear power in favor of more renewable methods of energy production and because of the government fully controlling the nuclear energy production process and not disclosing information to the public. [3,4] Policies have been set in place to further regulate the nuclear industry and have aimed to decrease the amount of nuclear power plants in the future. [5]

Strong Nuclear Presence

Nuclear energy has long been a staple of France and has had a significant impact on France. France's economy was severely affected by oil shocks in the 1970s and it was because of this that the French Government had decided to turn to nuclear power in efforts to restructure the countrys energy dependency on oil as well as to gain energy independence. [6] This has led to the development of a strong nuclear presence in France and decreasing CO 2 emissions in France dating back to 1980 to 2000. France contributes the least CO 2 out of major European powers as nuclear energy is envisaged to contribute to only 6% of Global CO 2 emissions come 2050. [7] France's nuclear industry has been consistently supported by the government and policies and has set up an impermeable institutional setup to assure that nuclear power remains one of France's stable means of energy production. [8]

Issues with Nuclear in France

Despite the significant positive impact which nuclear energy has had on France's energy production, France has had issues in relation to nuclear energy. These issues include health risks, lack of communication with the public and civilian protests. One case of nuclear energy leading to significant health risks in France was the case of increased children and young adults with Leukemia living within the vicinity of nuclear plants and nuclear waste centers. A nationwide included 2,753 cases diagnosed in mainland France over 2002-2007 and 30,000 contemporaneous population controls. The last addresses were geocoded and located around the 19 nuclear power plants. [9] This issue calls into question the process of nuclear waste management in France as well as how much the public knows regarding nuclear plants and waste management. Another key issue is that the nuclear process is controlled by a centralized institution, the government, from start to finish keeping civilians unaware of the ongoing aspects of nuclear energy. Despite efforts from the French government to ensure that nuclear is not a political controversy, anti-nuclear protesters have been present in France since the 1980s. [10,11]

Transition Away

Due to issues with nuclear energy in France, the future of nuclear energy in France is not clear. Public opinion regarding nuclear energy production has begun to shift and this is largely due to how the government manages all information regarding nuclear energy and keeps the public in the dark. [10] This has led to growing protests regarding the government protection of the nuclear industry. [3] France has also passed a law to decrease their amount of nuclear energy production to 25% by 2050 in favor of promoting more renewable forms of energy production. [11] The lofty goal of 25% has been called into question and reports have fluctuated reporting that nuclear production will only decrease to 50% by 2050. [4,12]

In conclusion, the presence of nuclear energy in France has been strong in the past but there is currently a transition away from nuclear energy scheduled for 2050. Nuclear energy has been extremely imperative to the energy production of France. Initially starting as a means to gain energy independence and reduce CO 2 emissions, the nuclear energy program in France grew quickly and has resulted in 58 nuclear plants, like the Dampierre Plant seen in Fig. 1 and the Cattenom Plant seen in Fig. 2, and these 58 nuclear plants contribute to nearly 80% of the country's energy production. [1] Despite the immense presence nuclear energy has in France, issues regarding safety and government transparency with the people have led to protests against the heavy nuclear presence. [3,9] Public opinion and policy have begun to transition away from nuclear energy and have turned their attention towards more renewable forms of energy with efforts to reduce the amount of nuclear energy production to between 25% and 50% come 2050. [4,12]

© Emanuel Pinilla. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.

[1] M. Schneider, " Nuclear Power in France: Beyond the Myth ," Greens-EFA Group in European Parliament, December 2008.

[2] M. Hlaing, " The Push to Cut Nuclear Energy in France ," Physics 240, Stanford University, Fall 2017.

[3] D. Rucht, "Campaigns, Skirmishes and Battles: Anti-Nuclear Movements in the USA, France and West Germany ," Organ. Environ. 4 , 193 (1990).

[4] N. Maizi and E. Assoumou, "Future Prospects for Nuclear Power in France," Appl. Energy 136 , 849 (2014).

[5] C. Mathieu, "France: Reducing Nuclear Dominance and Promoting a Low-Carbon Energy System," in Sustainable Energy in the G20 , ed by S. Roehrkasten, S. Thielges and R. Quitzow, Institute for Advanced Sustaintable studies, December 2016, p. 45.

[6] J. B Ang, "CO 2 Emissions, Energy Consumption, and Output in France," Energy Policy 35 , 4772 (2007).

[7] N. Apergis et. al., "On the Causal Dynamics Between Emissions, Nuclear Energy, Renewable Energy, and Economic Growth," Ecol. Econ. 69 , 2255 (2010).

[8] M. Delmas and B. Heiman, "Government Credible Commitment to the French and American Nuclear Power Industries," J. Policy Anal. Manage. 20 , 433 (2001).

[9] C. Sermage-Faure et. al. , "Childhood Leukemia Around French Nuclear Power Plants - The Geocap Study, 2002-2007," Int. J. Cancer 131 , E769 (2012).

[10] F. R. Baumgartner, "Independent and Politicized Policy Communities: Education and Nuclear Energy in France and in the United States ," Governance 2 , 42 (1989).

[11] " ADEME Energy Transition Scenarios 2030/2050 ," French Environment and Energy Management Agency [Agence de l'Environnement et de la Maîtrise de l'Énergie], May 2014.

[12] G. Dubois and J. P. Ceron, "Tourism/Leisure Greenhouse Gas Emissions Forecasts for 2050: Factors for Change in France ," J. Sustain. Tour. 14 , 172 (2006).

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Edf: EDF estimates higher nuclear power generation in France for 2024

• Sep 3, 2024 Sep 3, 2024 2:42 am GMT

EDF estimates higher nuclear power generation in France for 2024

Thanks to the good industrial performance of France's nuclear fleet, EDF revises higher its estimate nuclear power generation in France for 2024. Initially estimated between 315-345TWh, nuclear power generation is now estimated between 340-360TWh 1 .

This higher nuclear power generation estimate is based on improved performance of outages and industrial control of stress corrosion inspections and repair work, and the absence of major climatic event during summer.

The Group has implemented the START 2 2025 action plan aimed at improving the operational efficiency of outages, since 2019. It covers various areas: industrialisation, capitalisation, and standardisation of outages preparation methods, a refined strategy for allocating resources and skills, including the setting up of pooled teams and more employee training in sensitive actions.

Since early 2024, eleven reactors have been reconnected to the grid before the scheduled date.

About EDF The EDF Group is a key player in the energy transition, as an integrated energy operator engaged in all aspects of the energy business: power generation, distribution, trading, energy sales and energy services. The Group is a world leader in low-carbon energy, with a low carbon output of 434TWh (1), a diverse generation mix based mainly on nuclear and renewable energy (including hydropower). It is also investing in new technologies to support the energy transition. EDF’s raison d’être is to build a net zero energy future with electricity and innovative solutions and services, to help save the planet and drive well-being and economic development . The Group supplies energy and services to approximately 40.9 million customers (2) and generated consolidated sales of €139.7 billion in 2023.

(1) See EDF’s 2024 URD sections 1.2.3, 1.3.2 and 3.1 (2) Customers are counted per delivery site. A customer may have two delivery points.

<hr />

1 Nuclear power generation estimated for its facilities currently in service (Detailed information on the Flamanville 3 project on REMIT publication sites). 2 START: Let’s all ensure successful unit shutdowns

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Nuclear Power in a Clean Energy System

About this report.

With nuclear power facing an uncertain future in many countries, the world risks a steep decline in its use in advanced economies that could result in billions of tonnes of additional carbon emissions. Some countries have opted out of nuclear power in light of concerns about safety and other issues. Many others, however, still see a role for nuclear in their energy transitions but are not doing enough to meet their goals.

The publication of the IEA's first report addressing nuclear power in nearly two decades brings this important topic back into the global energy debate.

Key findings

Nuclear power is the second-largest source of low-carbon electricity today.

Nuclear power is the second-largest source of low-carbon electricity today, with 452 operating reactors providing 2700 TWh of electricity in 2018, or 10% of global electricity supply.

In advanced economies, nuclear has long been the largest source of low-carbon electricity, providing 18% of supply in 2018. Yet nuclear is quickly losing ground. While 11.2 GW of new nuclear capacity was connected to power grids globally in 2018 – the highest total since 1990 – these additions were concentrated in China and Russia.

Global low-carbon power generation by source, 2018

Cumulative co2 emissions avoided by global nuclear power in selected countries, 1971-2018, an aging nuclear fleet.

In the absense of further lifetime extensions and new projects could result in an additional 4 billion tonnes of CO2 emissions, underlining the importance of the nuclear fleet to low-carbon energy transitions around the globe. In emerging and developing economies, particularly China, the nuclear fleet will provide low-carbon electricity for decades to come.

However the nuclear fleet in advanced economies is 35 years old on average and many plants are nearing the end of their designed lifetimes. Given their age, plants are beginning to close, with 25% of existing nuclear capacity in advanced economies expected to be shut down by 2025.

It is considerably cheaper to extend the life of a reactor than build a new plant, and costs of extensions are competitive with other clean energy options, including new solar PV and wind projects. Nevertheless they still represent a substantial capital investment. The estimated cost of extending the operational life of 1 GW of nuclear capacity for at least 10 years ranges from $500 million to just over $1 billion depending on the condition of the site.

However difficult market conditions are a barrier to lifetime extension investments. An extended period of low wholesale electricity prices in most advanced economies has sharply reduced or eliminated margins for many technologies, putting nuclear at risk of shutting down early if additional investments are needed. As such, the feasibility of extensions depends largely on domestic market conditions.

Age profile of nuclear power capacity in selected regions, 2019

United states, levelised cost of electricity in the united states, 2040, european union, levelised cost of electricity in the european union, 2040, levelised cost of electricity in japan, 2040, the nuclear fade case, nuclear capacity operating in selected advanced economies in the nuclear fade case, 2018-2040, wind and solar pv generation by scenario 2019-2040, policy recommendations.

In this context, countries that intend to retain the option of nuclear power should consider the following actions:

• Keep the option open:  Authorise lifetime extensions of existing nuclear plants for as long as safely possible. 
• Value dispatchability:  Design the electricity market in a way that properly values the system services needed to maintain electricity security, including capacity availability and frequency control services. Make sure that the providers of these services, including nuclear power plants, are compensated in a competitive and non-discriminatory manner.
• Value non-market benefits:  Establish a level playing field for nuclear power with other low-carbon energy sources in recognition of its environmental and energy security benefits and remunerate it accordingly.
• Update safety regulations:  Where necessary, update safety regulations in order to ensure the continued safe operation of nuclear plants. Where technically possible, this should include allowing flexible operation of nuclear power plants to supply ancillary services.
• Create a favourable financing framework:  Create risk management and financing frameworks that facilitate the mobilisation of capital for new and existing plants at an acceptable cost taking the risk profile and long time-horizons of nuclear projects into consideration.
• Support new construction:  Ensure that licensing processes do not lead to project delays and cost increases that are not justified by safety requirements.
• Support innovative new reactor designs:  Accelerate innovation in new reactor designs with lower capital costs and shorter lead times and technologies that improve the operating flexibility of nuclear power plants to facilitate the integration of growing wind and solar capacity into the electricity system.
• Maintain human capital:  Protect and develop the human capital and project management capabilities in nuclear engineering.

Executive summary

Nuclear power can play an important role in clean energy transitions.

Nuclear power today makes a significant contribution to electricity generation, providing 10% of global electricity supply in 2018.  In advanced economies 1 , nuclear power accounts for 18% of generation and is the largest low-carbon source of electricity. However, its share of global electricity supply has been declining in recent years. That has been driven by advanced economies, where nuclear fleets are ageing, additions of new capacity have dwindled to a trickle, and some plants built in the 1970s and 1980s have been retired. This has slowed the transition towards a clean electricity system. Despite the impressive growth of solar and wind power, the overall share of clean energy sources in total electricity supply in 2018, at 36%, was the same as it was 20 years earlier because of the decline in nuclear. Halting that slide will be vital to stepping up the pace of the decarbonisation of electricity supply.

A range of technologies, including nuclear power, will be needed for clean energy transitions around the world.  Global energy is increasingly based around electricity. That means the key to making energy systems clean is to turn the electricity sector from the largest producer of CO 2 emissions into a low-carbon source that reduces fossil fuel emissions in areas like transport, heating and industry. While renewables are expected to continue to lead, nuclear power can also play an important part along with fossil fuels using carbon capture, utilisation and storage. Countries envisaging a future role for nuclear account for the bulk of global energy demand and CO 2 emissions. But to achieve a trajectory consistent with sustainability targets – including international climate goals – the expansion of clean electricity would need to be three times faster than at present. It would require 85% of global electricity to come from clean sources by 2040, compared with just 36% today. Along with massive investments in efficiency and renewables, the trajectory would need an 80% increase in global nuclear power production by 2040.

Nuclear power plants contribute to electricity security in multiple ways.  Nuclear plants help to keep power grids stable. To a certain extent, they can adjust their operations to follow demand and supply shifts. As the share of variable renewables like wind and solar photovoltaics (PV) rises, the need for such services will increase. Nuclear plants can help to limit the impacts from seasonal fluctuations in output from renewables and bolster energy security by reducing dependence on imported fuels.

Lifetime extensions of nuclear power plants are crucial to getting the energy transition back on track

Policy and regulatory decisions remain critical to the fate of ageing reactors in advanced economies.  The average age of their nuclear fleets is 35 years. The European Union and the United States have the largest active nuclear fleets (over 100 gigawatts each), and they are also among the oldest: the average reactor is 35 years old in the European Union and 39 years old in the United States. The original design lifetime for operations was 40 years in most cases. Around one quarter of the current nuclear capacity in advanced economies is set to be shut down by 2025 – mainly because of policies to reduce nuclear’s role. The fate of the remaining capacity depends on decisions about lifetime extensions in the coming years. In the United States, for example, some 90 reactors have 60-year operating licenses, yet several have already been retired early and many more are at risk. In Europe, Japan and other advanced economies, extensions of plants’ lifetimes also face uncertain prospects.

Economic factors are also at play.  Lifetime extensions are considerably cheaper than new construction and are generally cost-competitive with other electricity generation technologies, including new wind and solar projects. However, they still need significant investment to replace and refurbish key components that enable plants to continue operating safely. Low wholesale electricity and carbon prices, together with new regulations on the use of water for cooling reactors, are making some plants in the United States financially unviable. In addition, markets and regulatory systems often penalise nuclear power by not pricing in its value as a clean energy source and its contribution to electricity security. As a result, most nuclear power plants in advanced economies are at risk of closing prematurely.

The hurdles to investment in new nuclear projects in advanced economies are daunting

What happens with plans to build new nuclear plants will significantly affect the chances of achieving clean energy transitions.  Preventing premature decommissioning and enabling longer extensions would reduce the need to ramp up renewables. But without new construction, nuclear power can only provide temporary support for the shift to cleaner energy systems. The biggest barrier to new nuclear construction is mobilising investment.  Plans to build new nuclear plants face concerns about competitiveness with other power generation technologies and the very large size of nuclear projects that require billions of dollars in upfront investment. Those doubts are especially strong in countries that have introduced competitive wholesale markets.

A number of challenges specific to the nature of nuclear power technology may prevent investment from going ahead.  The main obstacles relate to the sheer scale of investment and long lead times; the risk of construction problems, delays and cost overruns; and the possibility of future changes in policy or the electricity system itself. There have been long delays in completing advanced reactors that are still being built in Finland, France and the United States. They have turned out to cost far more than originally expected and dampened investor interest in new projects. For example, Korea has a much better record of completing construction of new projects on time and on budget, although the country plans to reduce its reliance on nuclear power.

Without nuclear investment, achieving a sustainable energy system will be much harder

A collapse in investment in existing and new nuclear plants in advanced economies would have implications for emissions, costs and energy security.  In the case where no further investments are made in advanced economies to extend the operating lifetime of existing nuclear power plants or to develop new projects, nuclear power capacity in those countries would decline by around two-thirds by 2040. Under the current policy ambitions of governments, while renewable investment would continue to grow, gas and, to a lesser extent, coal would play significant roles in replacing nuclear. This would further increase the importance of gas for countries’ electricity security. Cumulative CO 2 emissions would rise by 4 billion tonnes by 2040, adding to the already considerable difficulties of reaching emissions targets. Investment needs would increase by almost USD 340 billion as new power generation capacity and supporting grid infrastructure is built to offset retiring nuclear plants.

Achieving the clean energy transition with less nuclear power is possible but would require an extraordinary effort.  Policy makers and regulators would have to find ways to create the conditions to spur the necessary investment in other clean energy technologies. Advanced economies would face a sizeable shortfall of low-carbon electricity. Wind and solar PV would be the main sources called upon to replace nuclear, and their pace of growth would need to accelerate at an unprecedented rate. Over the past 20 years, wind and solar PV capacity has increased by about 580 GW in advanced economies. But in the next 20 years, nearly five times that much would need to be built to offset nuclear’s decline. For wind and solar PV to achieve that growth, various non-market barriers would need to be overcome such as public and social acceptance of the projects themselves and the associated expansion in network infrastructure. Nuclear power, meanwhile, can contribute to easing the technical difficulties of integrating renewables and lowering the cost of transforming the electricity system.

With nuclear power fading away, electricity systems become less flexible.  Options to offset this include new gas-fired power plants, increased storage (such as pumped storage, batteries or chemical technologies like hydrogen) and demand-side actions (in which consumers are encouraged to shift or lower their consumption in real time in response to price signals). Increasing interconnection with neighbouring systems would also provide additional flexibility, but its effectiveness diminishes when all systems in a region have very high shares of wind and solar PV.

Offsetting less nuclear power with more renewables would cost more

Taking nuclear out of the equation results in higher electricity prices for consumers.  A sharp decline in nuclear in advanced economies would mean a substantial increase in investment needs for other forms of power generation and the electricity network. Around USD 1.6 trillion in additional investment would be required in the electricity sector in advanced economies from 2018 to 2040. Despite recent declines in wind and solar costs, adding new renewable capacity requires considerably more capital investment than extending the lifetimes of existing nuclear reactors. The need to extend the transmission grid to connect new plants and upgrade existing lines to handle the extra power output also increases costs. The additional investment required in advanced economies would not be offset by savings in operational costs, as fuel costs for nuclear power are low, and operation and maintenance make up a minor portion of total electricity supply costs. Without widespread lifetime extensions or new projects, electricity supply costs would be close to USD 80 billion higher per year on average for advanced economies as a whole.

Strong policy support is needed to secure investment in existing and new nuclear plants

Countries that have kept the option of using nuclear power need to reform their policies to ensure competition on a level playing field.  They also need to address barriers to investment in lifetime extensions and new capacity. The focus should be on designing electricity markets in a way that values the clean energy and energy security attributes of low-carbon technologies, including nuclear power.

Securing investment in new nuclear plants would require more intrusive policy intervention given the very high cost of projects and unfavourable recent experiences in some countries.  Investment policies need to overcome financing barriers through a combination of long-term contracts, price guarantees and direct state investment.

Interest is rising in advanced nuclear technologies that suit private investment such as small modular reactors (SMRs).  This technology is still at the development stage. There is a case for governments to promote it through funding for research and development, public-private partnerships for venture capital and early deployment grants. Standardisation of reactor designs would be crucial to benefit from economies of scale in the manufacturing of SMRs.

Continued activity in the operation and development of nuclear technology is required to maintain skills and expertise.  The relatively slow pace of nuclear deployment in advanced economies in recent years means there is a risk of losing human capital and technical know-how. Maintaining human skills and industrial expertise should be a priority for countries that aim to continue relying on nuclear power.

The following recommendations are directed at countries that intend to retain the option of nuclear power. The IEA makes no recommendations to countries that have chosen not to use nuclear power in their clean energy transition and respects their choice to do so.

• Keep the option open:  Authorise lifetime extensions of existing nuclear plants for as long as safely possible.
• Value non-market benefits:  Establish a level playing field for nuclear power with other low carbon energy sources in recognition of its environmental and energy security benefits and remunerate it accordingly.
• Create an attractive financing framework:  Set up risk management and financing frameworks that can help mobilise capital for new and existing plants at an acceptable cost, taking the risk profile and long time horizons of nuclear projects into consideration.
• Support new construction:  Ensure that licensing processes do not lead to project delays and cost increases that are not justified by safety requirements. Support standardisation and enable learning-by-doing across the industry.
• Support innovative new reactor designs:  Accelerate innovation in new reactor designs, such as small modular reactors (SMRs), with lower capital costs and shorter lead times and technologies that improve the operating flexibility of nuclear power plants to facilitate the integration of growing wind and solar capacity into the electricity system.

Advanced economies consist of Australia, Canada, Chile, the 28 members of the European Union, Iceland, Israel, Japan, Korea, Mexico, New Zealand, Norway, Switzerland, Turkey and the United States.

Reference 1

Cite report.

IEA (2019), Nuclear Power in a Clean Energy System , IEA, Paris https://www.iea.org/reports/nuclear-power-in-a-clean-energy-system, Licence: CC BY 4.0

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Edf: edf estimates higher nuclear power generation in france for 2024.

EDF estimates higher nuclear power generation in France for 2024

Thanks to the good industrial performance of France's nuclear fleet, EDF revises higher its estimate nuclear power generation in France for 2024. Initially estimated between 315-345TWh, nuclear power generation is now estimated between 340-360TWh 1 .

This higher nuclear power generation estimate is based on improved performance of outages and industrial control of stress corrosion inspections and repair work, and the absence of major climatic event during summer.

The Group has implemented the START 2 2025 action plan aimed at improving the operational efficiency of outages, since 2019. It covers various areas: industrialisation, capitalisation, and standardisation of outages preparation methods, a refined strategy for allocating resources and skills, including the setting up of pooled teams and more employee training in sensitive actions.

Since early 2024, eleven reactors have been reconnected to the grid before the scheduled date.

About EDF The EDF Group is a key player in the energy transition, as an integrated energy operator engaged in all aspects of the energy business: power generation, distribution, trading, energy sales and energy services. The Group is a world leader in low-carbon energy, with a low carbon output of 434TWh (1), a diverse generation mix based mainly on nuclear and renewable energy (including hydropower). It is also investing in new technologies to support the energy transition. EDF’s raison d’être is to build a net zero energy future with electricity and innovative solutions and services, to help save the planet and drive well-being and economic development . The Group supplies energy and services to approximately 40.9 million customers (2) and generated consolidated sales of €139.7 billion in 2023.

(1) See EDF’s 2024 URD sections 1.2.3, 1.3.2 and 3.1 (2) Customers are counted per delivery site. A customer may have two delivery points.

1 Nuclear power generation estimated for its facilities currently in service (Detailed information on the Flamanville 3 project on REMIT publication sites). 2 START: Let’s all ensure successful unit shutdowns

PR-2024 Nuclear output estimate

Geoelectric studies in earthquake hazard assessment: the case of the Kozlodui nuclear power plant, Bulgaria

• Original Paper
• Open access
• Published: 02 September 2024

Cite this article

You have full access to this open access article

• S. Kovacikova   ORCID: orcid.org/0000-0003-2600-175X 1 ,
• G. Boyadzhiev 2 &
• I. Logvinov 3  

The study presents the results of geoelectric research for seismic risk assessment on the example of the Kozlodui nuclear power plant in Bulgaria. The image of the geoelectric structure in the study area was obtained using one-dimensional inverse electrical resistivity modeling of the full five-component magnetotelluric data and quasi-three-dimensional inverse conductivity modeling of the geomagnetic responses recorded during the summer 2021 field campaign. According to the presented results, the geoelectrically anomalous structure is divided into two levels. The near-surface anomalous structure in the immediate reach of human geotechnical activity corresponds to the electrically conductive sedimentary fill. The mid-crustal layer is coincident with the low seismic velocity zone at the brittle and ductile crust interface, revealed in previous studies. The presented results imply that the geological environment is not affected by large faults capable of transmitting seismic energy from tectonically active areas, however, in further studies, attention should be paid to the strike-slip fault systems adjacent to the study area.

Avoid common mistakes on your manuscript.

1 Introduction

Due to the contrasting electrical properties of the geological environment, geoelectric methods can be used to address a variety of engineering geological tasks related to the natural hazard assessment in karst (Satitpittakul et al. 2013 ) or landslide studies (Lapenna et al. 2003 ), in quarry operation (Magnusson et al. 2010 ), in hydrogeology (Parks et al. 2011 ) or in the construction of critical infrastructure facilities (Di et al. 2020 ).

The construction and operation of civil nuclear installations are governed by strict safety regulations issued by the International Atomic Energy Agency (IAEA). Their neglect or underestimation can lead to tragic consequences. Designing and installing nuclear facilities in tectonically active areas always pose a danger (Nadirov and Rzayev 2017 ; Ahmed et al. 2018 ), but unexpected intraplate seismicity can also be documented in stable ancient terranes (e.g. Chattopadhyay et al. 2020 ) and even apparently historically inactive faults can be potentially risky (Faure Walker 2021 ). Although these strategic facilities are currently equipped with seismic early warning systems (Wieland et al. 2000 ) and spatial displacements are monitored by geodetic networks implementing Global Navigation Satellite (GPS) System data (e.g. Savchyn and Vaskovets 2018 or Manevich et al. 2021 ), integration of other geological and geophysical data is desirable to ensure maximum safety. Seismic events can be accompanied or preceded by a range of phenomena such as isotopes emissions (Sano et al. 2016 ; Zafrir et al. 2020 ) or meteorological phenomena (Morozova 2012 ; Guangmeng and Jie 2013 ). A correlation has been observed between earthquakes and tides (Scholz et al. 2019 ). Prior to an earthquake, electromagnetic (EM) emissions may be recorded around the future epicenter as a result of tectonic forces (Mavrodiev et al. 2015 ; Petraki et al. 2015 ). When assessing seismic risk, however, recording of the natural EM field variations can be used not only for above-mentioned immediate monitoring of earthquake precursors. Due to the enhanced electrical conductivity of mineralized fluids migrating in faults and fracture systems, magnetotelluric (MT) and magnetovariational (MV exploiting only the magnetic EM field components) methods with a depth range covering levels from the earth’s surface through the crust to the mantle are established procedures, for example in geothermal exploration (e.g. Gasperikova et al. 2015 ) or studies of magmatic systems (Wynn et al. 2016 ). Likewise, the contrasting electrical properties of fluids can also be used in seismic risk studies to identify fluid pathways in faults and delineate potential hazard zones. Numerous studies address the topic of the association of low resistivity zones and seismicity with active strike-slip zones (Bourlange et al. 2012 ; Hoskin et al. 2015 ; Adam et al. 2016 ), and different scenarios are presented depending on the zone geometry, mechanical conditions of rocks, degree of deformation, porosity and hydrogeology, with both highly permeable and mechanically locked segments (e.g. Unsworth and Bedrosian 2004 ; Kaya et al. 2009 ; Ritter et al. 2014 ). Water and fluids of both surface meteoric and deep origin, penetrating fault systems, play substantial role in these systems. Shear deformation promotes the formation of interconnected networks for fluid migration, and high-pressure fluids promote fault creep. Creeping segments tend to be subject to frequent microseismicity, while rare strong earthquakes may occur at the transition between creeping and locked zones. Earthquake foci typically trace the boundary between high- and low-resistivity features, corresponding to the stress accumulation and brittle deformation zones (e.g. Convertito et al. 2020 ). Within the conductors themselves the stress is redistributed to meet the equivalent rheology and the fluid hydrodynamics. The measured MT data can thus help identify potentially risky areas and delineate zones of increased seismicity, which is crucial when designing large-scale engineering facilities.

When studying seismic hazard, it is important not only to map surface weakened geological structures with which human geotechnical activities directly interact, but also to track the deep course of faults and trace the deep origin of phenomena observed on the earth’s surface (Suzuki et al. 2000 ). The use of the MT method in solving strategic projects, such as site selection for nuclear power plants, was proposed by Adam and Vero ( 1990 ). Thus, the MT method can expand knowledge about the tectonic structure in the vicinity of objects of interest and provide additional information that can be used in evaluating the measures necessary to increase the safety of strategic facilities. As an example of such a procedure, in this paper we present the results of a case study of the deep geoelectric structure in the area of the Kozlodui nuclear power plant in Bulgaria, initiated by the National Institute of Geophysics, Geodesy and Geography of the Bulgarian Academy of Sciences (NIGGG-BAS) and the National Science Fund to update the National Emergency Prevention Action Plan.

2 Geologic setting and geophysical data

The position of the Balkan region is controlled by the dynamics of the Mediterranean seismic belt, and although the Moesian Plate, as a promontory of the East European Platform, nestled between the Southern and Serbian Carpathians and the Northern Balkans, seems to be a relatively rigid block, it nevertheless participates in the relative movements of the Eurasian, African and Arabian tectonic plates (Stanciu and Ioane 2017 ). As a result, the Moesia and its Danube part is cut by the faults of the Carpathian-Balkan arch trend and by transverse faults into a system of basement blocks and has a complex deformation behavior with neotectonic activity along a number of fault structures.

Kozlodui nuclear power plant (KNPP) is located in the southwestern, seismically least active part of the Moesian Plate (Fig.  1 a). However, the relative proximity of continuously tectonically active fault systems may carry the risk of noticeable earth movements. About 300 km northeast (see inset in Fig.  1 a) is located persistently highly geodynamically active Vrancea area with four-to-five medium depth events with magnitudes M ≥ 6.5 per century and the largest recorded shock of 7.9 (e.g. Petrescu et al. 2021 ). From the west, the Moesian Plate is bounded by a continuously tectonically active fault system (M reaching 4), including the Timok and Cerna faults (TF-CF, inset in Fig.  1 a), linking the Carpathians with the Balkanides (Bala et al. 2015 ; Vangelov et al. 2016 ; Mladenovic et al. 2019 ; Krstekanic et al. 2021 ; Oros et al. 2021 ).

Geological setting— a The major tectonic zones of Bulgaria with the position of the Moesian Plate and Vrancea seismicity zone in the incut (from Cavazza et al. 2004 ): TF-CF—Timok-Cerna fault zone, KNPP—Kozlodui nuclear power plant, PAG—Panagjurishte geomagnetic observatory, green rectangle—study area; b Simplified tectonic map of the northwestern Bulgaria (modified after Cavazza et al. 2004 ; Kounov et al. 2017 ) with red crosses of experimental site network—MV (small) and full MT (big); faults (cross-hatched belts): Blk-Sub-Balkan, NFB-Northern Forebalkan, Vlm-Vinishte-Lom (Gostilski), Tsb—Tsibritsa, Ogs—Ogosta, Isk—Iskar, SMs – South Moesian, Dnb—Danube, Mtr—Motru, Jiu—Jiu fault (Dachev and Kornea 1980 ; Georgiev and Shanov 1991 ), thick dashed line—southern border of the Moesian Plate, magenta line—electrified railway (Bulgarian State Railways: https://www.bdz.bg ), M-BS—Makresh-Black Sea seismic profile (Dachev 1988 )

Several structural complexes can be identified within the Moesian Plate. Precambrian metamorphic rocks and Upper Paleozoic (Carboniferous to Permian) formations are covered by Triassic to Cenozoic sediments. On the Bulgarian territory, two large tectonic structures are distinguished on the Moesian Plate, the Lom depression, where the KNPP is located, and the North-Bulgarian uplift. East and north-east of the Lom depression, mainly on the Romanian territory, the Alexandria depression is delimited (Chemberski and Botoucharov 2013 ). Based on geophysical data (Dachev and Kornea 1980 ; Dachev et al. 1994 ), the total thickness of sediments of the Lom and Alexandria depressions reaches about 9 km (Fig.  2 a). The thickness of the Cenozoic sediments of the Lom depression reaches 1000 m (Fig.  2 b) (Zagorchev 2009 ). The Lom depression basement is formed by lowest tectonic blocks nested among the Danube fault in the north, Northern Forebalkan in the south and Vinischte-Lom and Iskar faults in the west and east respectively, separated from each other by the Ogosta and Tsibritsa faults (Fig.  1 b). The Vinishte-Lom fault is a strike-slip feature of the larger Oltenia tectonic zone cutting across a series of tectonic structures in the central part of the Balkan peninsula (Bala et al. 2015 ).

a Depth contours of the consolidated basement in km (dashed lines); b Contours (in m) of the top of the Upper Cretaceous complex (Zagorchev 2009 ); c Schematic section of sedimentary rock resistivity in Northern Bulgaria (solid line) and the Balkan region (dotted line) (Dobrev et al. 1975 ); d Schematic S sed map of sedimentary rocks (dashed contours in Siemens) of the KNPP area (red star in all subfigures) according to Abramova et al. ( 1994 ) (private comm.); Green line—Lom depression boundary

2.1 Geoelectric characteristics

According to the results of laboratory and geoelectric field experiments (Hermance 1995 ; Haak and Hutton 1986 ; Nover 2005 and others), the electrical resistivity (ρ) of crystalline rocks of the continental crust significantly exceeds 1000 Ω∙m. Below is information on the lithological composition of sedimentary rocks and their resistivity according to Dobrev et al. ( 1975 ).

The geological section of Northern Bulgaria is characterized by a wide distribution of two types of red-bed strata: Permian–Triassic (compacted clay rocks, conglomerates, breccia conglomerates, sandstones – with ρ varying from 16 to 45 Ω∙m) and Triassic-Jurassic. Middle Triassic oil and gas bearing limestones and dolomites up to 650 m thick are characterized by ρ varying between 100 and 400 Ω m. A thick Malm-Valanginian (late Jurassic-early Kretaceous) complex with ρ varying from 130 to 3600 Ω m appears in the Moesian section. Cretaceous and Pliocene carbonate facies of the Lom depression are characterized by ρ of 40–250 Ω∙m. Regional features of the ρ distribution of sedimentary rocks according to logging data are shown in (Fig.  2 c). Similar values are also given in other publications (Nikolova 1980 ; Dachev 1988 ; Chemberski and Botoucharov 2013 ).

The most characteristic geoelectric parameter of the sedimentary cover is the integrated longitudinal conductivity (conductance) S sed  = D/ρ, where D is the layer thickness. Based on geological-geophysical and well logging data, L.M. Abramova (2013 personal communication), the initiator of previous deep EM studies in Bulgaria (Abramova et al. 1994 ), has compiled a schematic S sed map of the Balkanides and the Moesian Plate in Bulgaria. This map has been updated with new information on the thickness, composition, and geoelectric parameters of the Cenozoic sediments of the Lom depression, obtained as a result of the interpretation of MTS (MT sounding) curves (Logvinov et al. 2021 ). Using a similar method, a schematic S sed map was constructed for the Romanian territory (Demetrescu 2013 ). According to rough estimates (based on data on the thickness of sediments and their ρ), S sed of surface sediments overlying the crystalline basement rocks on the territory of the Balkanides does not exceed 50 Siemens. Figure  2 d shows the S sed map for the south of the Moesian Plate and the adjacent part of the Balkans.

2.2 Seismic results and seismicity

The study area is intersected by the quasi-latitudinal regional seismic Makresh-Black Sea profile (Figs. 1 , 3 ). From west to east along the profile, the thickness of sediments of all ages decreases. P-wave Seismic velocities for terrigenous and terrigenous-carbonate sedimentary formations of the Moesian Plate along the M-BS profile (Fig.  3 a) vary from 2 to 4.5 km/s (Dachev 1988 ). Lower velocities are typical for Cenozoic sediments.

a Structure of the earth's crust along the Makresh-Black Sea (M-BS) seismic profile (Dachev 1988 ; Dachev et al. 1994 ). 1—sedimentary layer and seismic boundaries in it, 2—the Moesian Plate basement (numbers—seismic velocities, km/s), 3—Moho boundary, 4—supposed crustal zones of reduced seismic velocity. b , c Seismicity of the KNPP region for the period of years 1973–2020 (see sources in the text); fault zones Tsb, Dnb, SMs, Isk, Mtr, Jiu, NFB—see Fig.  1 b: b earthquake hypocenters by depth (in km); c) earthquakes by magnitude (thick circles with a numeral—strongest events with M > 3); crosses—unknown magnitude. Differences in the distribution of earthquake foci in subfigures ( b ) and ( c ) are given by the absence of depths/magnitudes for some events in the catalogues mainly before 2007

According to the seismic logging results, the seismic velocity of Paleogene-Neogene terrigenous deposits does not exceed 3.2 km/s (Volvovsky and Starostenko 1996 ). Both in the upper and lower consolidated earth's crust, low-velocity layers are distinguished along the profile (Fig.  3 a). The depth to the upper boundary of these layers is about 15 km and 27–30 km, their thickness is about 5 km and the seismic wave velocity decrease with respect to the surrounding environment is 0.5–0.7 km/s (Dachev et al. 1994 ).

Earthquakes are one of the most disastrous natural phenomena, the impact of which must be taken into account in the operation of nuclear facilities. Over the past 50 years, more than 15,000 earthquakes have been registered in Bulgaria, including the area belonging to the Moesian Plate, and some 750 events have been documented in the vicinity of the KNPP ( http://crustal.usgs.gov/geophysics/htm ; http://www.isc.ac.uk/iscbulletin/search/catalogue ; http://www.emsc-csem.org/Earthquake ; http://service.iris.edu/irisws/fedcatalog/1/ ; https:// earthquake.usgs.gov/earthquakes/search/; https://doi.org/10.7914/SN/BS ). The strongest events in the area around the KNPP occurred in 1987 in the northwestern tip of the Lom depression at the Tsibritsa, Motru and Danube faults tectonic knot at a depth of 10 km with a magnitude 3.3; another with a magnitude 3.7, and apparently related to the contact of the Danube fault with the branch of the Jiu fault, occurred in 1994 at the depth of 10 km, and another, with a magnitude of 4.4, took place in 2014 northeast of the study area in Romania at a depth of 12.1 km, near the junction of the Iskar, Danube and Jiu faults. The distribution of the events closest to the KNPP by depths and magnitudes is shown in Fig.  3 b and c respectively. For some events (specifically before 2007), depths or magnitudes are not specified in the catalogs cited above (hence the differences in the Figs.  3 b and c). It can be seen that a significant number of events occur south of the KNPP within a radius of 50 km (mainly already in the Pre-Balkans). The earthquakes seem to be linked to the intercrossing of the Ogosta, Tsibritsa and Iskar faults with the Northern Forebalkan fault (Fig.  3 b, c). The last represents an element of the Balkan fold-thrust belt, a complex system thrust onto Moesia from the south and dissected by transverse and oblique faults along which lateral displacements occur. Along the Ogosta fault with its hanging NW flank, there is a step-like dip towards the west. According to Georgiev and Shanov ( 1991 ), the block between Tsibritsa and Ogosta faults is still subsiding and the seismic activity of the Ogosta, Tsibritsa and Iskar faults is likely associated with the relative subsidence of the blocks between them. In recent years, several earthquakes with a magnitude exceeding 2 have been observed to the north and west of the KNNP. Tsibritsa fault with its hanging western flank is considered a satellite of the Motru fault, stretching north of the Danube in Romanian territory, which in turn is genetically connected to the Timok–Cerna fault system linking the Carpathians with the Balkanides (see Geological setting). Motru fault is also one of sources of seismic activity in the study area. It is deep-rooted, in the northwest, on Romanian territory, it is noticeably seismically active, and both left-lateral translation and descending movements occur along it. Some events seem to be related to the contact of the Danube fault with the Jiu fault–another active fault running on the Romanian territory from the Southern Carpathians in the NW–SE direction.

3 MT experimental data and inversion results

Geoelectric measurements were performed in the summer of 2021 using two GEOMAG-2 fluxgate magnetometers owned by the Institute of Geophysics of the National Academy of Sciences of Ukraine and the Institute of Mathematics and Informatics of the Bulgarian Academy of Sciences, ensuring registration of variations of MT field components with high sensitivity threshold (Dobrodnyak et al. 2014 ). The studies belong to the category of regional experiments, the purpose of which is to identify possible conductivity anomalies in the KNPP region. MT field observations were carried out at 21 points (Fig.  1 b). The distance between observation points was 10–15 km. The density and selection of locations for the installation of observation points were limited by local infrastructure and agricultural conditions.

EM field records in the study area were affected by significant disturbances associated with the proximity of electrified railroads, pipelines, power lines and other installations. Typically, interferences from these sources can have a significant impact at distances of up to 15–20 km. Figure  1 b shows the position of the KNPP and the nearest electrified railway, the presence of which automatically limited the area of the experiment. Interference on the magnetic components of the MT field decreases in proportion to the cube of the distance from the interference source. Taking into account the above, it was decided to register the magnetic components at the closest possible distance from the KNPP.

A detailed description of the processing of the recorded data and the distortion and dimensionality analysis were presented in Logvinov et al. ( 2021 ). Data processing was performed using Ladanivsky ( 2003 ) and Varentsov ( 2007 ) codes. The first phase of the geoelectric study was completed by estimating the parameters of impedance (Z) and the vertical magnetic transfer functions (VMTF) within the single-site processing scheme. Conditioned registration of the EM field electrical components was performed at four sites (Btn, Frn, Brv, Brn, see Fig.  1 b) and as a result, Z estimates (and derived apparent resistivity and impedance phase) were obtained for periods from 20 to 6400–8100 s. Meanwhile, the VMTF parameters were estimated at all observation points in the form of real (C u ) and imaginary (C v ) induction vectors (Schmucker 1970 ), presented on maps in the form of induction arrows, for the periods from 10–20 to 4900–10800 s.

3.1 1D inversion of MTS data

The nearby electrified railway and the measuring sites layout limited the data interpretation. Therefore, the first step was to estimate the geoelectric section parameters at the sites Btn, Frn, Brv, Brn by one-dimensional (1D) inversion of the interpreted MTS curves over the entire recorded period range. The results of 1D interpretation using two different inversion codes were also presented in Logvinov et al. ( 2021 ). The D + algorithm (Parker and Whaler 1981 ) approximates the geoelectric section through a finite number of layers of zero thickness and finite conductance isolated by a non-conductive medium, while the OCCAM 1D inversion (Constable et al. 1987 ) results in a section with smoothly varying conductivity. The minimum and maximum MTS curves obtained using the Eggers ( 1982 ) method were taken as experimental in the period range from a few seconds to 10 4  s. Before applying the inversion procedure, the MTS curves had to be normalized to eliminate galvanic effects on the MT field. Galvanic distortions arise as a result of the interaction of near-surface geoelectric heterogeneities and lead to a static shift of MTS amplitude curves (Berdichevsky and Dmitriev 2008 ). The normalization consisted in restoring the position of low-frequency asymptotes reflecting the electrical conductivity of the lower levels of the tectonosphere. It is assumed that at depths exceeding 400 km, horizontal changes in electrical conductivity are small, and the MTS curves obtained in different regions should converge at periods exceeding 3 h. In practice, the normalization of MTS curves usually consists in shifting the low-frequency branches of the MTS amplitude curves (ρ curves) along the vertical axis so that they match the ρ curve corresponding to the regional geoelectric structure of the study region (if the MTS phase curves agree with the reference curve). For the study area, data from the Panagjurishte geomagnetic observatory (PAG, 24.177°E, 42.515°N, Fig.  1 a) for the years 1988–2015 were used as a reference curve (Srebrov et al. 2013 ; Ladanivskyy et al. 2019 ). For 1D inversion, the recorded MTS curves were integrated with the reference curve at periods 2⋅10 4 –2⋅10 7  s (Fig.  4 ).

Minimum and maximum experimental (circles) and model MTS curves at the sites Frn, Brv, Btn, Brn for two azimuths integrated at the period of 2·10 4  s with the reference data from the PAG observatory using D+ , OCCAM (from Logvinov et al. 2021 ) and 1D anisotropic inversion codes (Pek and Santos 2006 )

The 1D interpretation of the MT data already presented in Logvinov et al. ( 2021 ) was newly supplemented by a 1D anisotropic inversion using all components of the impedance tensor (Pek and Santos 2006 ). It should be noted here that the technique does not mean searching for real physical anisotropy in the earth and is used purely to apply the equivalent of a 1D anisotropic layered medium to the MTS curves in two directions at each site. To accommodate all impedance tensor components, the anisotropic inversion error floor in the anisotropic inversion was preset to 5%. Anomalous layers (conductors) with ρ much smaller than those lying above and below are identified on the inverse 1D models (Fig.  5 a). The differences in the distribution of geoelectric parameters calculated by OCCAM and anisotropic inversions are mainly due to the fact that in the OCCAM method, the experimental MTS curves were corrected to take into account galvanic distortion. Low resistivities of sedimentary rocks according to both inversion methods appear at depths of less than 1 km. According to the results of the anisotropic inversion, a low resistivity feature (ρ of about 10 ohmm) is identified at the Brv site at depths of about 4 km.

a Geoelectric resistivity sections according to 1D models calculated using Occam inversion procedure (from Logvinov et al. 2021 ) and 1D anisotropic inversion by Pek and Santos ( 2006 ). 1—supposed zones of reduced seismic velocity along the M-BS seismic profile (Figs. 1 , 3 ). b Earth’s crust structure along the corresponding segment of the M-BS seismic profile (see Fig.  3 a), stars—seismic events within a distance of 10 km from the sites Frn, Btn, Brv and Brn ( a ) and from the M-BS seismic profile ( b )

The resistivity of the rocks underlying the sediments exceeds 100 ohmm. In both inverse models, at Frn, Brv and Brn, a conductor with a resistivity of 10 ohmm is distinguished at depths of 20 (+/− 5) km. The most distorted records of MT field variations were obtained at Btn, which was caused by the proximity of the high-voltage power line and affected the interpretation parameters and the inversion results. Comparison of the obtained geoelectric 1D models with the seismic section along the M-BS profile (Fig.  5 b) shows the coincidence of conductors with low-velocity layers in the depth interval 15–20 km.

3.2 Quasi-3D inversion of MV data

The next step in the interpretation of the 2021 geoelectric survey data was the modeling of the conductance S distribution of the sedimentary cover and the earth's crust using a quasi-3D inverse technique based on the Price thin-sheet approach and data fitting using Tikhonov parametric functional minimization with conjugate gradient optimization and the maximum smoothness stabilizing (Kováčiková et al. 2005 ). The purpose of the quasi-3D inversion application was: (1) to determine the spatial position of anomalous features in the studied area and explain the behavior of MV parameters; (2) to compare the obtained results with other geological and geophysical data.

The thin-sheet method involves only the magnetic MT field components. VMTF data from 21 stations over the entire period range of 50–2500 s were used in the inversion. The study area (90 km × 90 km) was divided into tiles with a side of 6 km × 6 km. The cell size was chosen with respect to the applied periods and the distance between observation points. The vertical conductivity distribution in the quasi-3D model was represented by a 1D layered section (Fig.  6 a–c) selected taking into account previous geophysical and geological data, geoelectrical characteristics of the sedimentary cover (see the previous divisions) and an earlier MT survey in the Bulgarian territory by Srebrov et al. ( 2013 ). Analysis of equivalent current systems at different depths commonly used in thin-sheet modeling (Banks 1979 ) did not provide the expected depth estimate of the upper level of the crustal anomaly source due to shielding by conductive surface sediments filling the Lom depression. The smooth pattern of the current function distribution becomes unstable and breaks down at a depth of 4 km as an effect of the continuation of the field below the upper boundary of the source, in this case represented by the conductive sediments of the Lom depression (see supplementary material). Therefore, the depth of the upper boundary of the crustal anomaly was taken from the 1D inversion results, which assumed the most conductive crustal objects in the depth interval of about 15–20 km (Fig.  5 ). The initial thin-sheet model for the iterative inversion procedure was represented by a homogeneous sheet with a uniform normal conductance distribution, located at a fixed depth.

Results of the quasi-3D inversion—distribution of the conductance S (Siemens) in the thin sheet with corresponding input 1D sections: a thin sheet at the surface and recorded real and imaginary induction arrows for the period of 50 s; b thin sheet at the depth of 15 km and real and imaginary experimental induction arrows for the period of 2500 s; c two sheet model with the surface sheet (subfigure a ) and a crustal sheet at 15 km and real experimental and model induction arrows for the period of 2500 s; d experimental and model imaginary induction arrows for the same model as in the subfigure c . Faults (cross-hatched belts and other details as in Fig.  1 b; L—Lom depression, M—Moesian Plate, B—Balkans (Fore-Balkan)

Generally, the validity of the thin sheet approach is limited from below at short periods by near-surface disturbances and from above at long periods by source effects. Although given the geoelectric conditions in the Lom depression, the penetration depth at the shortest periods 50 and 100 s should allow reaching 20 and 30 km respectively, a series of inversions of geomagnetic responses at different depths at these periods showed that the best fit of the model geomagnetic responses and the experimental ones was achieved when the conductive thin sheet was placed on the surface, i.e. the resulting conductivity models reflect mainly the distribution of subsurface conductive sediments. The surface sheet substituted a sedimentary layer with an average depth of 4 km and a conductivity of 0.025 S/m (Fig.  6 a). Starting with the period of 900 s, the geoelectric image of crustal depths predominates in the conductivity models. This is accompanied by the reversal of the imaginary induction arrows pointing at short periods (50, 100 s) in the direction corresponding (or close) to the real arrows to the opposite orientation (Fig.  6 a, b). To depict the distribution of conductivity in the earth's crust, in inversions at periods of 900, 1600 and 2500 s, a thin sheet was placed at a depth of 15 km. However, the resulting conductivity model seemed to be influenced by the sub-surface sediments (Fig.  6 b). Therefore, to separate the effect of conductive sediments and the crustal anomaly source, a two-sheet model was chosen in the inversion of the VMTF’s at the periods 900, 1600 and 2500 s. The first layer with a thickness of 4 km corresponding to the average thickness of sediments of the Lom depression (Fig.  2 c) was substituted by a surface thin sheet with a fixed conductance derived from the single-sheet inversion at the period of 50 s (Fig.  6 a). The second sheet was immersed at a depth of 15 km (Fig.  6 c, d).

Modelling experiments to select the normal conductance at the thin sheet edges showed that the best data fit was obtained with a value of 100 S for the surface sheet simulating the sedimentary cover. The most satisfactory normal conductance for the crustal sheet was 1000 S (Fig.  6 a–c). In the inversion, the data weight multiplying the parametric functional (squared during the procedure) was uniform – 0.01, selected taking into account amplitudes of the recorded magnetic transfer functions (maximum 0.3). Starting with the normal conductance in the thin sheet (or two sheets), the inversion procedure converged typically after 20–35 iterations and finished reaching the data weight value between two iterations. Specifically, the presented surface model at a period of 50 s (Fig.  6 a) converged after 32 iterations, the one-sheet crustal model at 2500 s (Fig.  6 b) stopped after 24 iterations, the two-sheet model (Fig.  6 c) converged after 29 iterations. Data fit for the final two-sheet model is shown in Fig.  6 c, d.

4 Discussion

On Fig.  7 , the correlation of conductivity both in near-surface sediments and at mid-crustal depths (sub-figures a and b respectively) with seismicity is imaged. As was mentioned before in the Introduction, earthquake foci at both subfigures appear outside or at the margins of the conductors (both horizontally and vertically).

Comparison of S near the surface ( a ) and at a depth of 15 km ( b ) (from Fig.  6 a and c respectively) and seismic events above (dots) and below (crosses with focal depths) the mid-crustal conductive layer. Faults (cross-hatched belts) and other details as in Fig.  1 b and Fig.  6 ; L—Lom depression, M—Moesian Plate, B—Balkans (Fore-Balkan)

According to the quasi-3D inversion results, near-surface anomalous conductivity distribution in the study area appears to be controlled by electrically conductive sediments of the Lom depression (Fig.  6 a). One anomaly close to the junction of the Iskar and Northern Forebalkan fault appears in the area of distribution of the Pleistocene loam complexes (Angelova 2001 ). Two anomalies west and east of the river Ogosta seem to correspond to areas of Neogene (Pliocene) clays distribution (Angelova 2008 ). The anomalous conductivity area at the intersection of the Danube Tsibritsa and Motru faults (and in the confluence of the Danube and Tsibritsa rivers) may be related to the intrusion of highly mineralized water from a deeper aquifer (Toteva and Shanov 2021 ).

At mid-crustal depths (Figs. 6 c, 7 ), the basement of the most subsiding block is non-conductive, separated by the Ogs, Tsb and NFB faults from the more conductive surroundings. An anomalous electrical conductivity structure appears at the intersections of the Ogosta fault with the Danube and South Moesian faults. Moderate seismic activity and recent vertical movements have been documented on the Ogosta fault (Georgiev and Shanov 1991 ; Angelova 2008 ), however, the hypocenters are concentrated at its intersection with the Northern Forebalkan fault and mostly south of the latter, while the central part of the conductive feature itself remains unaffected by seismic events (Fig.  7 ). Most of the hypocenters are located above the depth of the mentioned conductor (black dots in Fig.  7 ). The entire western and southwestern margin of the study area is also significantly electrically conductive. This electrically anomalous area is located west of the Tsibritsa fault and southwest of the Northern Forebalkan fault, which delimits the area that already belongs to the Balkanides (Fore Balkans) from the north. The highly conductive area may be associated with the effect of the significantly strike–slip TF-CF zone west of the study area (see Fig.  1 a). It may also represent the deep source of the near-surface anomaly at the intersection of the Danube and Tsibrica faults in the above-mentioned area of occurrence of the mineralized water spring.

Previous 1D inverse models at 4 points indicated the existence of the low resistivity objects in the depth interval of 15–25 km (Fig.  5 a). This corresponds to the crustal conductive feature identified by quasi-3D modeling in the area around the Btn site; Frn and Brv are located at the edge of this conductor, while Brn is located outside the conductive area. Also, the results of the anisotropic 1D inversion do not indicate the existence of a significant decrease in electrical resistivity at crustal depths. The results of both methods also point to the existence of near-surface low-resistivity/conductive layers around the Btn and Brv points.

An anomalous conductivity mid-crustal layer with an upper boundary at approximately 15 km resulting from the thin-sheet inversion also correlates with the seismic low-velocity layer revealed by Dachev et al. ( 1994 ) (Figs. 3 a, 5 ). Earthquake foci within a 10 km radius around the Brn, Frn, Brv, Btn sites (Fig.  7 ) were also superimposed on their 1D resistivity depth distribution (Fig.  5 a). Similarly, events occurring within 10 km to both sides of the M-BS seismic profile were shown (Figs. 5 b, 7 ). From the presented sample, it can be seen that most of the events took place at shallow depths above the low-velocity layers (and none at their depths). Mid-crustal reflective low-seismic-velocity layers with an upper boundary at a depth of about 15 km were described by Gutenberg ( 1954 ) and further reported in various studies and various regions (e.g. Zorin et al. 2002 ; Zhan et al. 2020 ). In seismically active regions, low-velocity zones associated with the presence of partial melt, residual magma, heat escaping from the mantle, or frictional heating at fault zones exposed to shear between contact blocks act as waveguides channeling seismic waves during earthquakes (e.g. Zhao et al. 2000 ; Qin et al. 2018 ; Nagar et al. 2021 ). However, low velocity layers are also widespread in stable cold crust regions, where they cannot be explained by increased heat and the presence of melt. Low velocity layers can often correlate in space with electrically conductive layers (Eaton 1980 ; Vanyan et al. 2001 ) and their mutual mechanism can be interpreted as a consequence of rheological stratification and processes at the brittle/ductile crust transition, influencing the increase in porosity, geometry of pore spaces, the amount of pore fluids, their salinity and consequently controlling both elasticity and electrical conductivity of rocks (Gough 1986 ; Marquis and Hyndman 1992 ; Unsworth and Rondenay 2013 ), although graphitization along fission planes due to ductile shear is also mentioned as an alternative mechanism of increased conductivity (Simpson 1999 ; Glover and Adam 2008 ). The fluid origin is most likely associated with dehydration (Jones 1992 ), while the most reasonable explanation for the increase in porosity itself is, according to Pavlenkova ( 2004 ), the dilatancy phenomenon, again associated with the influx of hydrous fluids. The low velocity/high conductivity layers are thought to act as detachment zones, separating weak and brittle parts of the crust on which most faults, except deep fault zones cutting the whole crust, flatten. Episodic seismic events occur above such interfaces or at their periphery.

The presented results support the outputs of other available studies (Antonov 2000 ; Groudev and Petrova 2017 ) concerning the geodetic monitoring, stress tests and natural hazard assessment for the KNPP operation, which state the stability and safety of the geological environment in the study area. According to regional GPS studies by Kotzev et al. ( 2001 ) overall kinematic pattern shows that the only tectonically active structures in northern Bulgaria lie east of the domain hosting the Lom basin. The western and southern boundaries of the domain are characterized by N-S to NE-SW extension. In the northwest, a system of NE-trending faults (the Vinishte-Lom fault in the study area, Fig.  1 b) shows left-lateral movement. The eastern and southeastern boundaries of the domain (along the Yantra river east of the study area, Fig.  3 a) is not distinct, however, with moderate right-lateral strike-slip and NE-SW compression. As already mentioned in Sect.  2.2 Seismic results and seismicity, the northern boundary is formed by the Danube dip-slip fault with a recently uplifted (in response to extension) northern block. Geodetic survey by Valev et al. ( 2016 ) focused on the area around the KNPP registered only weak and slow deformation of a variable character in the KNPP area. Also, results of DInSAR studies (Differential Synthetic Aperture Radar Interferometry) by Drakatou et al. ( 2015 ) reported the stability of the region with a negligible rate of deformation ranging between − 1 and + 1.5 mm/year. Seismic surveys by the Common Depth Point (CDP) and refraction methods for the exploration of coal-bearing horizons (Yaneva and Shanov 2015 ) prove the uniformity of the tectonic regime from the end of the Dacian (Pliocene) period to the present. The oil and gas prospecting seismic studies (Toteva and Shanov 2021 ) have noted the deep Tsibritsa fault topographically predetermining the eponymous Danube tributary, however, they do not address the question of whether the fault is active.

Although the presented MT survey results are consistent with the mentioned above studies that suggest no special measures for the KNPP safety, further research should be directed towards the creation of a complete 3-D image of the study area using 3D-inversion procedures, which would depict the vertical geoelectrical structure in more detail. These would require a set of broadband fully 5-component MT measurements with reference measurements and inter-station processing, with the presented results serving as a-priori input information. The dataset should be also supplemented with MT and GDS results from the adjacent Romanian part of the Moesian platform in the north (Stanica and Stanica 2011 ) and with completely missing data from the Serbian territory, from the arched belt of faults, namely the TF-CF strike-slip system, bending The Moesian plate from the west.

5 Conclusion

Although the main focus of engineering geology is in the area within the reach of human activity and its interaction with earth processes, it should not be limited to the earth's surface, since deep tectonic processes can significantly affect any engineering and geotechnical work. The results of a case study of a geological structure in the area of the Kozlodui nuclear power plant in Bulgaria showed how the analysis of geoelectric features can complement the complex of geological and geophysical information for seismic hazard assessment.

1D inverse resistivity modeling based on MT data recorded during the summer 2021 field experiment indicated the existence of mid-crustal low-resistivity features coincident with a seismic low-velocity layer revealed by a previous regional seismic survey. The subsequent quasi-3D inversion provided insight into the sub-surface sedimentary structure as well as the electrical conductivity distribution in the mid-crust. An electrically anomalous feature with an upper boundry at a depth of about 15 km appears at the intersection of the Ogosta with South Moesian and Danube faults. The conductive western and southwestern margin of the investigated area is probably related to the strike-slip fault systems bounding the Moesian Plate from the west. The mid-crustal high electrical conductivity and low seismic velocity layer is assumed to correspond to the transition zone between the brittle and ductile crust. Seismic events may occur at its outer boundary, however, no large fault structures with the potential to transfer seismic energy from tectonically active areas were revealed in the study area. The presented results support the conclusions of previous seismic hazard studies and confirm that the Kozlodui nuclear power plant is located in an area with a stable geological environment, however, in further research, the results of studies covering the fault system linking the Carpathians with the Balkanides west of the studied area should be included.

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This work was carried out as part of the implementation a scientific project «Research on Partial Differential Equations and their applications in Modelling of non-linear processes», funded by Bulgarian National Science Fund, contract KP-06N42/2 and partially supported by scientific project 0117U000117 «Deep processes in the crust and upper mantle of Ukraine and formation of mineral deposits» funded by National Academy of Sciences of Ukraine. We thank the editor and the reviewers for their helpful comments and suggestions.

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Kovacikova, S., Boyadzhiev, G. & Logvinov, I. Geoelectric studies in earthquake hazard assessment: the case of the Kozlodui nuclear power plant, Bulgaria. Nat Hazards (2024). https://doi.org/10.1007/s11069-024-06867-9

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Applied Nuclear Science offers many tangible benefits to the United States and to the world. The Low Energy Nuclear Physics Community recognizes the societal importance of applied research, and strongly encourages support for this exciting and growing field with funding and beam time allocations that enable critical discovery science that will improve our lives and make us all safer.

Rare isotopes are necessary for research and innovation and must be available.  

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At the Democratic Convention, a Historic Nomination

What story did the democrats tell about kamala harris and will it be enough to win.

This transcript was created using speech recognition software. While it has been reviewed by human transcribers, it may contain errors. Please review the episode audio before quoting from this transcript and email [email protected] with any questions.

[BACKGROUND CHATTER]

I’m standing in a sea of people coming out of this vast convention. And people are holding signs, smiling. There’s confetti everywhere. There are balloons, white, red, and blue. And there’s a lot of excitement.

From “The New York Times,” I’m Sabrina Tavernise. And this is “The Daily” from inside the Democratic National Convention Hall, where Kamala Harris has just accepted her party’s nomination, becoming the first woman of color in US history to do so.

Today, the story this convention told about Harris and whether that story could be enough to win.

It’s Friday, August 23.

[SERENE MUSIC]

The work and prayers of centuries have brought us to this day. What shall our our legacy be? What will our children say? Let me in my heart, when my days are through, America, America, I gave my best to you.

On night one of the Democratic National Convention, the evening was really defined by this very emotional, quite bittersweet goodbye from President Biden.

And there’s nothing we cannot do when we do it together.

God bless you all. And may God protect our troops.

It was the closing of one chapter so that another could begin. It was Kamala Harris’s moment.

[UPBEAT JAZZ MUSIC]

So right now, it’s 7:40. We are on the floor at the Democratic National Convention. It is a crazy party atmosphere, which is like a massive understatement.

Day two kicked off with delegates gathering on the convention floor, casting their votes in a kind of symbolic way to make Harris the party’s nominee.

This giant festival of lights, people in cowboy hats, people with blinking bracelets, people with Christmas lights wrapped around their hats, heads, shoulders, people wearing donkey hats. I mean, it’s very, very, very celebratory in here.

We need to see that we’re moving on. We are turning a chapter in America.

How do you feel right now?

Awesome, excitement, energized. Ready to win this election.

I love it. I love it. People are just excited, electrified, and they’re just loving it, and they’re happy.

This has been the most electrifying event I’ve ever attended in my life. It’s my first convention. But what a convention to come for, right? To make history right now, as we charge forward to November 5, to elect the first female Black president. I’m excited.

So with Harris now the nominee, a new campaign slogan appeared everywhere. And that was, “A new way forward.” But in a campaign that’s just four weeks old, it was really an open question what “a new way forward” actually meant.

We’re not going back!

We’re not going back! We’re not going back!

And then over the course of the week, as speaker after speaker took the stage, we started to get an answer. The story of forward would be told through the story of Kamala Harris herself. And the question hanging over the week was really whether that story could appeal to a broad majority of Americans, voters outside of the convention hall who will ultimately decide the election.

[UPBEAT MUSIC]

Astead, welcome to the show.

Thank you for having me.

Again. The second time in a week. And I’m very excited for it.

So Astead, we had on the show on Monday to answer a question for us, that I think a lot of people have, which is, who is Kamala Harris? And you ended that conversation by saying that the Democratic Party also recognizes this reality, that for a lot of people, she is still this unknown quantity.

And that the party had a big task here at the convention this week, which was to find a way to finally tell her story. It does seem like they’ve tried to do that. Let’s walk through the case that they’re making for her. And what you’ve seen here in your reporting for your show, “The Run-Up.”

Yeah, I mean, I think that the Democrats have definitely laid out a case for her as a candidate, but also a story for her as a person. They have leaned into the different parts of her biography to really follow through on what, I think, is the best version of her campaign, which is a little bit for everybody. There is a story there about more moderate legislation, but pieces of progressive history. There’s different parts of her bio that speak to Black communities, immigrant communities.

Of course, the historic nature of her gender and the roles like that. And I really think it has followed through on what I expected for this week, which is that she seems to function politically as a mirror of some sort, where the party wants to position her as someone who basically, no matter what you’re looking for in terms of a vessel to beat Donald Trump, you can find it in this candidate.

Let’s dig into that more. Where did the convention start, that story?

Hello, Democrats!

Yeah, I think it really starts in her personal biography.

And I’m here tonight to tell you all about the Kamala Harris that I know.

They have told a story that she often tells about her being a first generation American.

Her mother moved here from India at 19.

And being a daughter of an immigrant mother who really raised two daughters in the Bay Area from working class roots. And that’s been a real thing that they’ve tried to own.

Kamala was not born into privilege. She had to work for what she’s got.

When she was young, she worked at McDonald’s.

They talk about her working at McDonald’s in college.

And she greeted every person without thousand watt smile and said, how can I help you?

I think it’s overall about trying to present this as someone who pulled himself up by bootstraps. It represents the American dream. And I think for Democrats, it really returns them back to the place they want to be. Democrats like thinking of themselves as a party who appeals to the diversity of America, both in racial ways, in gender ways, but also in class ways.

In Kamala Harris, we have a chance to elect a president who is for the middle class because she is from the middle class.

And I think they used other parts of her identity, specifically thinking about being the first Black woman to accept a major party’s nomination.

We know folks are going to do everything they can to distort her truth.

And I think Michelle Obama’s speech, specifically, spoke to the power and anxiety that sometimes that identity can bring.

My husband and I sadly know a little something about this.

For years, Donald Trump did everything in his power to try to make people fear us. See, his limited, narrow view of the world made him feel threatened by the existence of two hard-working, highly educated, successful people who happen to be Black.

And I would also say that it was an implicit response to what Republicans and others have been trying to say, talking about Kamala Harris as a DEI hire, someone who was only in their position because of their identity. But the way that Michelle Obama framed it was that those identities have power.

I want to know. I want to know. Who’s going to tell him, who’s going to tell him that the job he’s currently seeking might just be one of those Black jobs?

Just because someone the first to be in a position, does not mean that is the only reason in the position. But it also doesn’t make those identities meaningless. The fact that she is a Black woman should be seen as a strength, not as a weakness.

Is there a risk to that, though? I mean, by openly talking about race, is there a risk that goes too far and begins to alienate voters outside the convention out in the world who they need to win in November.

I mean, there’s always a risk. But I don’t really think so. Democrats have had increasing trouble with Black voters. There’s been a downturn in Black vote share all the way dating back to 2012.

In Biden’s now suspended candidacy, that was one of the things driving his polling weaknesses was kind of tepid reception from Black voters. A pitch to them is something that is a upside of the Kamala Harris campaign. And the hope that they could consolidate that community is where any Democratic nominee needs to be as a baseline.

We both got our start as young lawyers, helping children who were abused and neglected.

One thing I noticed that came up a lot during the speeches was her background as a prosecutor. How did the party present that part of her biography?

As a prosecutor, Kamala stood up for children who had been victims of sexual abuse.

She put rapists, child molesters, and murderers behind bars.

They talk about it in the way that I think fuels what they want to say is the reason she can take on Trump, that this is someone who has stood up to bullies before, who’s not going to be intimidated easily —

And Kamala is as tough as it comes.

— who’s tough, and who doesn’t shirk away from a challenge.

And she knows the best way to deal with a coward is to take him head on, because we all know cowards are weak. And Kamala Harris can smell weakness.

I think all of that adds up to say, you can trust this person to go up against Donald Trump. You can trust this person to go up against the Republican Party, because she’s not someone who is scared.

She never runs from a fight.

A woman, a fierce woman for the people.

But then, of course, we heard about another side of Kamala Harris, a more personal side.

Yeah, and I think this is the part of Kamala Harris where I think was kind of most missing in the presidential run. Frankly, it’s the part that she keeps most private. She is a warm family member and friend.

Hello to my big, beautiful blended family up there.

And I think what the speech from her husband did was really show and lay that out.

I got married, became a dad to Cole and Ella. Unfortunately, went through a divorce, but eventually started worrying about how I would make it all work. And that’s when something unexpected happened, I ended up with Kamala Harris’s phone number.

He talks about the kind of awkwardness of their first interaction.

I got Kamala’s voicemail, and I just started rambling. “Hey, it’s Doug.”

And I think you have a real kind of sense of their genuine connection to one another.

By the way, Kamala saved that voicemail. And she makes me listen to it on every anniversary.

Like, yes, this is someone who is tough, who is taking on corporations and cartels and all of that stuff by day. But this is someone who also makes a point to cook Sunday dinner for family every week.

And she makes a mean brisket for Passover.

And makes sure to really go close to his kids and is very close with her family.

That’s Kamala. She’s always been there for our children. And I know she’ll always be there for yours, too.

Going back to the last time the Democratic Party nominated a woman, Hillary Clinton, she had presented herself in a very different way. She kind of ran away from that stuff. She was saying, I don’t bake cookies, that’s not what I do. I’m kind of out there with the men, fighting.

And this convention and this candidate, Harris, is very different. She’s a newer generation. And she can do her career and bake cookies. Those things are not in conflict. This is a different type of woman leader.

This week we talked to Senator Elizabeth Warren on “The Run-Up,” and one of the things that she mentioned was she feels that there’s been a big change from 2016, even 2020 to now. Not just the amount of women in public office, but she said they don’t have to choose between sides of themselves. And I think that’s what diversity means.

Of course, Kamala Harris can be a tough politician and also bake cookies. Hillary Clinton did that, too. It was just that she was told that was not the way that she had to present herself. What Kamala Harris is benefiting from is there’s a greater space and ability to choose multiple things at once. And so particularly if others are going to talk more directly about gender or race or other things, that kind of frees her from having the burden of doing that herself.

And in fact, Hillary Clinton, herself, did speak, of course, on day one. She talked about that glass ceiling in the history that has led to now, including her own experience in 2016.

Yeah, I thought the Hillary Clinton speech was really powerful. I think a lot of the speakers put this moment in historical context, both politically and personally.

My mother, Dorothy, was born right here in Chicago before women had the right to vote. That changed 104 years ago yesterday. And since that day, every generation has carried the torch forward. In 1972, a fearless Black congresswoman named Shirley Chisholm —

— she ran for president. In 1984, I brought my daughter to see Geraldine Ferraro, the first woman nominated for vice president. And then there was 2016, when it was the honor of my life to accept our party’s nomination for president.

The last time I was here in my hometown was to memorialize my mother, the woman who showed me the power of my own voice. My mother volunteered at the local school.

I’m the proud granddaughter of a housekeeper, Sarah Daisy, who raised her three children in a one-bedroom apartment. It was her dream to work in government, to help people.

My grandmother, the woman who helped raise me as a child, a little old white lady born in a tiny town called Peru, Kansas.

I want to talk now about somebody who’s not with us tonight. Tessie Prevost Williams was born in New Orleans not long after the Supreme Court ruled that segregated public schools were unconstitutional. That was in 1954, same year I was born. Parents pulled their kids out of the school.

There was a way that I think the candidacy and the person was placed in a long legacy, both about gender identity and racial identity that kind of teed up this Thursday as a culminating moment, both politically and I think, in a broader historical context.

Together, we put a lot of cracks in the highest, hardest glass ceiling. And you know what? On the other side of that glass ceiling is Kamala Harris raising her hand and taking the oath of office as our 47th president of the United States!

I wish my mother and Kamala’s mother could see us. They would say, keep going. Shirley and Jerry would say, keep going!

I think you can do a lot to set up a candidate to be in a good position. All of this stuff adds up to some part of the puzzle, but the biggest piece is the candidate themself. At the end of the day, they have to close the deal. And I think this moment is her chance to tell her own story in a way that sometimes she has not decided to. And that’s still what this whole convention success and failure will ride on.

We’re going to watch tonight. We’re going to watch with our colleague, Reid Epstein. And you are going to have a great episode of “The Run-Up” on Friday. We will all be tuning in.

Thank you. I appreciate you doing this, Sabrina.

Really thanks a lot, Astead.

Are you a delegate?

Sorry, we caught you mid French fry eating. What’s your feeling about Kamala and what her story has been? Are you getting to know her this week? Are there things you’ve learned about her this week?

Yeah, I’m learning more and more as we go along. The more and more I learn about her, the more I’m impressed with her. I mean, she worked at McDonald’s when she was going to college to try to pay her way through.

Her very small beginnings. Not a trust fund baby type of thing. I relate to that. Like, I was on food stamps this year. So it’s like if she can do it with that background, it gives everybody hope.

Hillary was my girl. When Hillary ran, I championed her as well. But I didn’t feel this way as I feel about Harris. I’m like, do I want to run for office? If she can do it, I can. She looks just like me, right? She represents, she works at McDonald’s. She paid for every. It’s relatable. And that’s what everybody needs.

We’re going to break that glass ceiling. I’m getting teary, teary in my eyes. And it just means so much to be inclusive.

[WHIMSICAL MUSIC]

What does it mean to you that Kamala Harris is a woman? What does it mean to you that she’s a Black woman?

To have a Black woman become the president of the United States, and for her to turn the world upside down in 30 days, to know that I’m in the midst of this miraculous history is phenomenal.

One delegate who really stood out to us was Beverly Hatcher, a 76-year-old Black woman from Texas.

I was raised by a wonderful Baptist mama. I just lost her. But I am who I am because of my mother. We were always pushed to do whatever we wanted to do. I’ll never forget. I wanted to be a majorette. I taught myself, because we had no money for, what is it called, lessons

And a majorette is like the baton twirler, right?

Yes. And when I did finally try out in my 11th grade, I won right off. And my classmates, who were predominantly white, as years have gone by, have told me at class reunions and stuff, Beverly, the sleepy town of Wellington woke up.

Oh, my god, we got a Black girl getting ready to be the head majorette. But it happened because I had the drive and the will. My mother and my family stood behind me, and didn’t miss a parade, or a football game, or a basketball game.

And you see that in Harris?

Beverly, what would your mom say if she saw this?

My sisters have been telling me every day how proud my mom is. And I’m just happy. I’m happy to make her happy. Yeah.

We women, who have had mothers like Kamala, like Michelle, I remember Hillary’s mother, we women value their strength and their wisdom. And we’re just glad that they gave us a legacy to pass it on.

Thank you very much.

We’ll be right back.

Reid, hello.

OK. Kamala Harris just wrapped up her acceptance speech. Before we talk about what she said and the case she presented, tell us how her campaign was thinking about the stakes of this moment.

Sabrina, this evening was one of two opportunities, along with the debate next month, for her to speak to tens of millions of people at once. And so for that, the stakes were really high.

Her goal was to present herself as a serious person and a serious candidate, who was not the candidate who flamed out in 2019 or the unsteady vice president from the beginning of her term. She had to show that she had the gravitas to be the commander in chief, the political aptitude to reach out to the middle, and also to progressives in her party all at the same time.

A very tall order. Tell us how she went about doing that.

Good evening, everyone. Good evening.

Well, she started talking around 9:30 Chicago time to a packed United Center with 14,000 or 15,000 people, many, many wearing all white, the color of the suffragettes, a color that makes a statement just by wearing it. And when Harris took the stage —

— they erupted in a cheer that forced her for a couple of minutes to wait before she could start talking.

Thank you. OK, let’s get to business. Let’s get to business. All right.

And what did she finally say once she started talking?

She told the story of her life.

The path that led me here in recent weeks was, no doubt, unexpected. But I’m no stranger to unlikely journeys.

My mother, our mother, Shyamala Harris, had one of her own. And I miss her every day, and especially right now.

She talked about the influence of her mother, who raised her and her sister.

And she also taught us, “And never do anything half-assed.” And that is a direct quote. [LAUGHS]

She spoke about her family’s humble beginnings in Oakland.

Before she could finally afford to buy a home, she rented a small apartment in the East Bay.

Then she started talking about her career as a prosecutor.

In the courtroom, I stood proudly before a judge and I said five words.

She brought back one of the lines that she used in her 2020 campaign about how when she stood up in a courtroom, she began with the same words.

Kamala Harris for the people.

And she said she would bring that same philosophy to the White House, that she was not working for specific individuals, but for the people at large.

And so on behalf of the people —

Eventually she did a bigger wind up to formally accepting the nomination.

— on behalf of every American, regardless of party, race, gender, or the language your grandmother speaks —

And listed the people on whose behalf she did so.

— on behalf of everyone whose story could only be written in the greatest nation on Earth —

It was really a kind of a feat of speech writing to build up to this big emotional moment.

— I accept your nomination to be president of the United States of America.

And what did you make of that, how she was doing that?

It was building up this speech to be a serious political document and present her as a serious figure in this moment. And so she still has to prove to people that she is capable of being the commander in chief and running the country.

And how does she try to prove that she’s capable of being a commander in chief?

What she did was try to draw the distinction between herself and Donald Trump.

In many ways, Donald Trump is an unserious man. But the consequences, but the consequences of putting Donald Trump back in the White House are extremely serious.

And she warns that Trump would not have guardrails on him if he were elected to a second term.

Just imagine Donald Trump with no guardrails.

And how he would use the immense powers of the presidency of the United States not to improve your life, not to strengthen our national security, but to serve the only client he has ever had, himself.

The speech was very clear-eyed about the stakes of the election.

They know Trump won’t hold autocrats accountable because he wants to be an autocrat himself.

There was a whole section in the middle of the speech where she ticked through, one by one, a whole series of warnings about things that Trump would do to the country if he were back in the White House.

Get this, he plans to create a national anti-abortion coordinator and force states to report on women’s miscarriages and abortions.

Simply put, they are out of their minds.

What else stuck out to you?

It was remarkable, the section of the speech where she talked about Gaza.

President Biden and I are working around the clock, because now is the time to get a hostage deal and a ceasefire deal done.

She did not veer too far to the left.

I will always stand up for Israel’s right to defend itself.

She managed to say things that would be appealing to both sides.

President Biden and I are working to end this war, such that Israel is secure, the hostages are released, the suffering in Gaza ends, and the Palestinian people can realize their right to dignity, security, freedom, and self-determination.

It was a remarkable moment to hear the arena erupt at the end of that section, to hear her support for both the Israelis and the Palestinians reveal that kind of enthusiasm, after the party has been really ripped apart for months about how to handle the situation.

Fellow Americans, I love our country with all my heart.

She ended this speech with a paean to patriotism.

We are the heirs to the greatest democracy in the history of the world.

She dove headlong into the American exceptionalism argument that is native to Republicans and to older generations of politicians, like Joe Biden.

It is now our turn to do what generations before us have done. Guided by optimism and faith to fight for this country we love. To fight —

But is not something you always hear from younger Democrats, who are a little less comfortable with some of the flag waving.

Let’s vote for it. And together, let us write the next great chapter in the most extraordinary story ever told. Thank you. God bless you and may God bless the United States of America. Thank you all.

She seemed to really be taking aim at this criticism of her, which is that she’s this radical California liberal and she can’t be trusted with the keys to the country.

I mean, that was one of the tasks that she had tonight, was to make the argument, particularly to voters in the middle, the suburban voters that used to vote for Republicans, but have been repelled by Trump and driven to Democrats in the last several years, that they can vote for her without worrying that she’s some kind of Bernie Sanders acolyte.

And some of that is based on the way she ran her last presidential campaign. Some of it, frankly, is because she’s a Black woman from California. And that the voters who will determine this election are voters in less diverse states, for the most part.

So Reid stepping back here, it feels worth remembering just where we were at the end of the Republican National Convention that was just over a month ago. Things couldn’t have felt more different. The GOP was on top of the world, while the Democrats were in disarray over Biden’s refusal to leave the race.

And now here we are. And it feels like things couldn’t be better for the Democrats. At least that’s the feeling I’m having coming out of this convention.

I mean, the whole race has turned upside down from where it was when we left Milwaukee. And Democrats are upbeat. They are confident. It is a party that is remarkably united behind their candidate.

But you have to remember, this election will be very close. It is, indeed, a game of inches in the key battleground states. And what she was trying to do was to present herself as someone who can be trusted as commander in chief to win over the tiny slices of the electorate that will determine the winner in places like Wisconsin, and Michigan, and Pennsylvania, Georgia, and Arizona.

And those are the states that will determine the election. And they have made a calculated decision that those voters needed to see her as a commander in chief, something they had not seen from her before. And we will see in the coming days and weeks whether she’s accomplished that in a way that brings enough of those people on board for her to win a term as president.

Reid, thank you.

Thank you, Sabrina. [WHIMSICAL MUSIC]

Here’s what else you should know today. On Thursday, the Supreme Court allowed Arizona Republicans, for now, to impose tougher voting requirements, including a new rule that people registering to vote there before the coming election must show proof of citizenship.

As a result, Arizonans newly registering to vote for this year’s presidential election must provide copies of one of several documents, such as a birth certificate or a passport, in order to prove that they are US citizens. Democrats have denounced the new rule as an attempt to prevent legal immigrants from voting.

And US Health officials have approved the latest slate of annual COVID vaccines, clearing the way for Americans six months and older to receive updated shots in the coming days. The approvals come amid a prolonged surge of COVID infections, which have risen all summer.

Remember to catch a new episode of “The Interview” right here tomorrow. This week, Lulu Garcia-Navarro talks with Jenna Ortega, the star of the Netflix series “Wednesday,” and the new “Bettlejuice” sequel, about her head-spinning success over the past few years.

One day I just I woke up in somebody else’s shoes. I felt like I had entered somebody else’s life. And I didn’t know how to get back to mine.

Today’s episode was produced by Lynsea Garrison, Rob Szypko, Jessica Cheung, Asthaa Chaturvedi, and Shannon Lin. It was edited by Rachel Quester, contains original music by Rowan Niemisto, Dan Powell, Diane Wong, and Marion Lozano, and was engineered by Chris Wood. Our theme music is by Jim Brunberg and Ben Landsverk of Wonderly.

[THEME MUSIC]

That’s it for “The Daily.” I’m Sabrina Tavernise. See you on Monday.

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Hosted by Sabrina Tavernise

Featuring Astead W. Herndon and Reid J. Epstein

Produced by Lynsea Garrison Rob Szypko Jessica Cheung Asthaa Chaturvedi and Shannon Lin

Edited by Rachel Quester

Original music by Rowan Niemisto Marion Lozano Dan Powell and Diane Wong

Engineered by Chris Wood

Listen and follow ‘The Daily’ Apple Podcasts | Spotify | Amazon Music | YouTube | iHeartRadio

Last night, at the Democratic National Convention, Vice President Kamala Harris accepted her party’s nomination, becoming the first woman of color in U.S. history to do so.

Astead W. Herndon and Reid J. Epstein, who cover politics for The Times, discuss the story this convention told about Ms. Harris — and whether that story could be enough to win the presidential election.

On today’s episode

Astead W. Herndon , a national politics reporter and the host of the politics podcast “ The Run-Up ” for The New York Times.

Reid J. Epstein , who covers politics for The New York Times.

Background reading

Kamala Harris promised to chart a “new way forward” as she accepted the nomination.

“The Run-Up”: It’s her party now. What’s different?

There are a lot of ways to listen to The Daily. Here’s how.

We aim to make transcripts available the next workday after an episode’s publication. You can find them at the top of the page.

The Daily is made by Rachel Quester, Lynsea Garrison, Clare Toeniskoetter, Paige Cowett, Michael Simon Johnson, Brad Fisher, Chris Wood, Jessica Cheung, Stella Tan, Alexandra Leigh Young, Lisa Chow, Eric Krupke, Marc Georges, Luke Vander Ploeg, M.J. Davis Lin, Dan Powell, Sydney Harper, Michael Benoist, Liz O. Baylen, Asthaa Chaturvedi, Rachelle Bonja, Diana Nguyen, Marion Lozano, Corey Schreppel, Rob Szypko, Elisheba Ittoop, Mooj Zadie, Patricia Willens, Rowan Niemisto, Jody Becker, Rikki Novetsky, Nina Feldman, Will Reid, Carlos Prieto, Ben Calhoun, Susan Lee, Lexie Diao, Mary Wilson, Alex Stern, Sophia Lanman, Shannon Lin, Diane Wong, Devon Taylor, Alyssa Moxley, Olivia Natt, Daniel Ramirez and Brendan Klinkenberg.

Our theme music is by Jim Brunberg and Ben Landsverk of Wonderly. Special thanks to Sam Dolnick, Paula Szuchman, Lisa Tobin, Larissa Anderson, Julia Simon, Sofia Milan, Mahima Chablani, Elizabeth Davis-Moorer, Jeffrey Miranda, Maddy Masiello, Isabella Anderson, Nina Lassam and Nick Pitman.

Astead W. Herndon is a national politics reporter and the host of the politics podcast “The Run-Up.” More about Astead W. Herndon

Reid J. Epstein covers campaigns and elections from Washington. Before joining The Times in 2019, he worked at The Wall Street Journal, Politico, Newsday and The Milwaukee Journal Sentinel. More about Reid J. Epstein

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