NUCLEAR ENERGY – thoughts round about

At a time when humanity needs more and more energy, nuclear energy raises many questions and controversies about the prospects for its development. You may not hear the rational voice of professionals among a variety of different opinions of nuclear defenders, competitors and opponents. Therefore, the Uatom.org Editorial Board is launching a platform for discussions between nuclear experts in the form of authors blogs.

Former ChNPP Chief Engineer, Chairman of the State Committee of Ukraine for Nuclear and Radiation Safety and Deputy Minister of Fuel and Energy of Ukraine Mykola Shteinberg is the first to open a new section. Its text is an invitation for experts to join the discussion.

Please note that Uatom.org editors may not share the position of authors in Section “Blogs”. The authors of the texts are solely responsible for the information in Section “Blogs”.

A consequence follows from a certain definite cause, and on the other hand,

if there is no definite cause, then a consequence is impossible.

Baruch Spinoza

 

Before doing something, you need to ask: what to do and why? Let’s ask ourselves: why do we need nuclear energy, and if so, what nuclear energy?

For thousands of years, people burned firewood, then coal, and then used oil and gas. Curiosity led them to nuclear energy. In August 1945, the effectiveness was tested and … for the vast majority of the planet’s inhabitants, word “nuclear” is associated with an explosion of colossal power (and relevant consequences) and with invisible and deadly radiation. We, power engineers, also did our best: Three Mile Island, Chornobyl.

Let’s focus on two aspects: do we need nuclear energy and why?

Without energy, life is not life. In the last 150 years, the world’s energy has increased 35 (!) times and passed three stages of development, whose duration decreased: 70, 50 and 30 years. The growth rate of energy consumption also slowed down: by 4.8, 4.2 and 1.6 times. It is predicted that the consumption of primary energy in the world will increase by 40% (on average by 1.1% annually) by 2040 compared to the period by 2010 – this is three times less than the average annual GDP growth, and the growth of energy consumption rates over the past 30 is also noticeably slower.

No radical changes to the global fuel basket are expected. Hydrocarbons will dominate. It is assumed that their share by 2040 will be 51-52%. The “slate stone breakthrough” has pushed back the threat of depletion of oil and gas resources.

According to the US Energy Information Administration, in 2007, the following was used as primary energy sources: oil – 36%, coal – 27.4%, natural gas – 23%. The share of fossil fuels was 86.4% of all primary energy sources in the world. Proven reserves of fossil fuels (in the years of production at the current rate): coal – 148 years; oil – 43 years; natural gas – 61 years.

The share of primary energy used for electricity production grows: 47% by 2040 compared to 36% by 2010. The transport sector remains an important driver of demand for fossil fuels (up to 80% of total oil demand by 2040). Efficiency increase of vehicles is the main constraining factor for the growth of fuel consumption. On average, car power in the world increased by 42% between 1990 and 2013, and fuel consumption decreased by more than a third (by 37%).

The increase in the consumption of fossil fuels leads to an increase in greenhouse gas emissions, primarily CO₂. Developed countries may be able to stabilize and even reduce CO₂ emissions, but this will not change the situation on a global scale.

Global warming, the term that has recently entered our lives, means an increase in the average temperature of the Earth’s climate system. It has been going on for over a century and its main cause is considered to be human activity. Not everyone agrees with this, however, the issue itself does disappear due to this, and its consequences do not become less serious, no matter is it recognized or not.

Currently, CO₂ concentration in the Earth’s atmosphere has reached 0.02-0.045 total % (250-450 ppm) – the maximum for the last 800 thousand years and possibly for the last 14 or 20 million years.

On 9 May 1992, the UN Framework Convention on Climate Change was adopted, whose essence is to achieve: “… stabilization of greenhouse gas concentrations in the atmosphere at a level that would not allow hazardous anthropogenic impact on the climate system …”. It is believed that it is necessary to keep warming in the range of 1.5-2.0 ° C until the end of the century. If more, it will be bad.

To strengthen the UN Framework Convention on Climate Change, on 12 December 2015, at a conference in Paris, an agreement was adopted regulating further measures to reduce CO₂ content in the atmosphere starting from 2020. Laurent Fabius, French foreign minister at the time, said this “ambitious and balanced” plan became a “landmark pivotal moment” in the fight against global warming. Unfortunately, it did not become, neither pivotal, nor landmark.

For almost 30 years, humanity has been struggling with climate issues without real progress towards the goal: the lack of rules and procedures to manage the process caused inconsistencies between political statements and actual state of affairs. According to estimates, it is still possible to meet this limit – 2.0 ° C, if no more than 500 billion tons of CO₂ will be released into the atmosphere from 2020 to the end of the century. However, the world already emits 40 billion tons of CO₂ a year. For example, the climate policies of China, Russia and Canada lead to warming by 5 ° C by the end of the century, the United States and Australia do not look much better (above 4 ° C). For EU, this index is 3-3.5 ° C. Calculations have shown that in order to meet 2.0 ° C, new fossil fuel power plants should no longer be commissioned in the world. Is it real? And what instead? What to do?

After all, the world needs electricity. The electrification of end users (industry, agriculture, transport, air conditioning, household appliances, and others) is a key element of development. It should be recalled that 11% of the world’s population still lacks access to electricity.

Renewable energy sources can and should play an important role, the increase in whose capacity by 2040 is expected to be more than 75% to the current level. Among renewable energy sources, hydroelectric power plants and pumped storage power plants are the most competitive. Geothermal installations shoe also good results, but the regions of their use are very limited.

The competitiveness of WPP (wind power plants) and SPP (solar power plants) is still supported by the state and, obviously, in the coming decades a significant part of renewable energy source technologies will need this support. The unpredictable operating mode of wind power plants and solar power plants (dispatchers of power systems have not yet learned how to control the wind and the sun) has more than once put even large power systems on the brink of collapse. These are intermittent (unstable) sources with unpredictable power generation schedules and these problems cannot be hidden. Almost everywhere, in parallel with WPPs and SPPs, standby capacities are being constructed, whose construction costs, as a rule, are “dissolved” in the state budgets. Yes, of course, you can compete, but what will it lead to? And how long will it last?

The issue is theoretically solved by forming economically and technically acceptable systems of energy accumulation and storage. Some progress has been made here, but the issue is still far from being solved, so the share of such renewable energy sources as WPP and SPP cannot exceed 30-40% of the installed capacity of the energy system if it is not possible to obtain electricity “from outside”.

In 2020, the world produced 26,659 TWh of electricity, including 7,166 in China, 4,461 in the United States, 3,277 in EU, and 1,579 in India. However, about 65% of this electricity is generated by power plants that burn organic fuel. It was assumed that their share will fall to 48% by 2040, but … Recent estimates suggest otherwise: the share of electricity produced using fossil fuels may be increased by 15-16% by 2040. Thermal power plants have made significant progress in increasing thermal efficiency, but emissions … For example, the world’s largest coal power plant with a power of 5780 MW in Taichung (Taiwan) is also the world’s largest source of CO₂ emissions (over 40 × 106 tons per year).

Currently in the world:

– 75.5% of all electricity is generated by non-renewable energy sources: coal (38.3%), natural gas (23.1%), oil (3.7%) and nuclear energy (10.4%);

– 24.5% of electricity is generated by renewable energy sources, including hydraulic energy, biomass, wind, geothermal, solar and tidal energy.

In general, the situation is far from optimistic. For the decarbonization of electricity by 2050, it is necessary that the share of low-carbon generation in electricity production be at least 83-85%, and the share of coal and gas be reduced to 12-15%. It is obvious that only renewable energy sources cannot solve the issue. So, what to do?

For more than 70 years, there is a nuclear energy sector in the world electrical energy industry. Globally, NPPs reduce CO₂ emissions by about 2.5 billion tons annually. It is the second largest source of low-carbon electricity production after hydraulic energy (in 2017, NPPs produced about 30% of all low-carbon electricity in the world).

In 2018, NPPs generated 2710 TWh of electricity, which is about 10% of total electricity consumption in the world. If 10% of the electricity generated today by nuclear energy were replaced by gas, pure fossil fuel, an additional 1,300 million tons of CO₂ would be emitted into the atmosphere (equivalent to the operation of an additional 250 million vehicles).

Calculations show that without nuclear energy the decarbonization issue cannot be solved. The US Energy Information Administration estimates that renewable energy sources and natural gas will be the most common energy sources in the world in 2015-2040. Renewable energy sources will be increased at a rate of 2.6-2.8% per year and by 2040 will provide 31% of electricity generation (the same share is given to coal). Models of smart and sustainable economic growth show that the low-carbon future requires nuclear energy to provide 17% of electricity generation (7617 TWh) in 2050-2060 (the installed capacity of NPP is estimated at 989 GW).

It seems that nuclear energy should “strive upwards”, because without it the issue of the global warming cannot be solved. Indeed, warming fighters starts, sometimes quite clearly, to speak in favor of increasing the role of nuclear energy. However, they do not want to understand that until the numerous discriminatory measures accumulated over three decades of anti-nuclear policy are eliminated, the situation will not change. First of all, it concerns the policy on the electricity markets.

The advantage of nuclear energy is low dependence of electricity prices on fuel costs, which is important to maintain a stable basis for economic development. The low level of CO₂ emissions puts it among the leaders in supplies of basic low-carbon electricity. According to these indexes, nuclear energy has no competitors.

According to IAEA, nuclear energy capacities will increase from 392.6 GW (2020) to 511 – by 2030, 641 GW – by 2040 and 748 GW by 2050. IAEA assumes that due to existing discrimination against nuclear energy in world markets, a significant and long-term decrease in the share of nuclear energy in world electricity production is possible. The total capacity of nuclear energy may decrease to 352 GW by 2030 and to 323 GW by 2040. The restoration to 356 GW is possible only until 2050.

IAEA prediction is conservative but probable. Many NPPs are expected to be decommissioned in the coming decades, which will not be compensated by introducing new capacities. This means that the goal of the Paris Agreement will not be achieved.

The World Nuclear Association (WNA) has published its own prediction: 930 GW of nuclear capacities by 2050 (17% of total electricity generation in the world). Achieving this goal requires the annual introduction of 10 GW at NPPs today, 25 GW by 2025 and 33 GW by 2050. In the mid-1980s, up to 31 GW per year were introduced.

There are other predictions, but all state one thing: the share of nuclear energy in electricity generation in 2040-2050 should be from 17 to 25%. Conceptually, nuclear energy can take up this challenge, but to implement its potential it is necessary to:

– equal conditions in the electricity markets for all generation types;

– harmonize regulatory control;

– form an integrated approach to safety of the electrical power system.

However, businesses are not interested in nuclear energy: they require guarantees against various political and economic risks, and they do not get them. Therefore, there is no reason to assume that in the period until 2040 the share of electricity production at NPPs at the global level will increase, so hot calls to combat global warming mean nothing – it is just a political chatter that is well known to all of us.

However, let’s switch off from environmental and political issues. What is nuclear energy in the world today? What can it offer?

The largest share belongs to pressurized water reactors (PWR): about 67% of the total amount. The second largest share – boiling water reactors (BWR): about 16% of the total amount. The third group – heavy water reactors (PHWR): about 11%. In 10-15 years, the operation of advanced gas-cooled reactors (AGR), as well as graphite water reactors (RBMK) will be mainly terminated within 10-15 years.

In recent years, Generation III + high safety reactors (all PWRs) have been commissioned. Russia has commissioned VVER-1200. China has started operation of EPR-1660 developed by AREVA (France) and AP-1000 constructed by Westinghouse (USA). APR-1400 units (South Korea) were put into operation in the South Korea and UAE.

The main area of Generation III + has been determined. This is PWR. An increase in the number of BWR is also possible. Both technologies are well-established for a long time both in terms of construction and in terms of operation. It is not worth expecting breakthrough technological solutions there. An increase in unit capacities is also not expected: the market does not require this. The power range of 900-1700 MW is covered and complies with large power systems requiring powerful units with a high safety level of the basic mode guaranteeing acceptable and stable electricity prices over a long period.

In recent years, small modular reactors (SMRs) have become a hot topic in discussions related to nuclear energy prospects. According to IAEA, about 70 SMR designs/concepts are being developed today. It is obvious that SMRs will not replace powerful nuclear units, but they occupy their niche, in particular, electricity and heat supply (also water desalination is possible) of remote settlements, metallurgical and chemical enterprises, military bases, etc., as well as implementation in countries that desperately need a sustainable electricity supply but do not have the necessary economic and social basis. The introduction of SMR in such countries will certainly make a significant contribution to reducing CO₂ and other greenhouse gas emissions.

Just in recent months, the interest of the thermal energy business has begun to show itself vigorously – fully understanding that environmental issues will force decommissioning of coal and then gas units, they became interested in the possibility of SMR placement on their sites.

SMR characteristics allow provision of their package supply and operation by operators of developed countries with the subsequent transfer to local operators as the relevant conditions are ensured. If legal issues of such an approach can be solved, the prospects for nuclear energy will become significantly more optimistic. A breakthrough is possible there, but it is unlikely to occur in 5-10 years.

The 20th anniversary of the Generation IV program (GEN IV) was celebrated in April 2021. It was founded by DOE (US Department of Energy) in 2000 and officially launched in mid-2001 to conduct studies for Generation IV nuclear systems, make them available for industrial use. The forum brings together 13 countries (Argentina, Australia, Brazil, Canada, China, France, Japan, South Korea, Russia, South Africa, Switzerland, the United Kingdom and the United States) and Euratom.

The program grew out of US plans to restart its nuclear program, which led to the recognition of a global approach to the deployment of new reactor technologies. Six reactor systems (five of them with fast neutron reactors) were selected with the purpose to:

– achieve a safety and reliability level, which eliminates the need for emergency response beyond the NPP site;

– form a sustainable nuclear energy with minimum waste;

– get advantages in life cycle cost in comparison with other energy sources and reduce the level of financial risk;

– prevent proliferation of nuclear material.

GEN IV systems should cover the entire fuel cycle, regardless of the size and type of facilities. That is why the attention of GEN IV is focused on breeder reactors and fuel cycle closure, because this is what places nuclear energy into the category of renewable energy sources and ensures a long-term energy well-being of mankind.

From 1973 to 2009, France operated the prototype of the Phénix fast reactor, whose main objectives development and operation objectives were to achieve the maximum possible fuel burnup and close the fuel cycle. Both tasks were successfully accomplished, and in 1997, the American Nuclear Society listed Phénix as a historical monument of nuclear energy.

Equally significant was the experience of EBR-II (USA), which was the basis of the American Integral Fast Reactor (IFR) Program, establishment of an integrated system of breeder-pyrometallurgical processing and fuel production system in a single package. When the possibility of fuel cycle closure was shown for the sodium-cooled breeder reactor, including fuel processing, the emphasis shifted to tests of materials and fuel (oxides of metals and ceramics, carbides and nitrides of uranium and plutonium)

Two unique tests were performed on EBR-II, which confirmed the inherent safety characteristics of this reactor type. In the first case, reactor coolant pumps were disconnected at full power when SCRAM was blocked. The reactor power dropped to zero in about five minutes. No damage of the reactor fuel was detected. In the second test, the reactor was operated also at full power, but secondary coolant flow rate was stopped. Reactor shutdown took place a few minutes later without SCRAM, operators and without damage. EBR-II is also listed as a historical monument of nuclear energy.

The list of countries and corporations included in the breeder – fuel cycle closure program is impressive. This suggests that the economy of the breeder – closed cycle system shows promising prospects, existing knowledge and experience confirm the possibility to achieve practical results. It is the area of the breeder – fuel cycle closure, where breakthrough results can be expected in the next 10-20 years.

The prospects of nuclear energy are difficult to assess without addressing such issues as the legal framework for nuclear safety, long-term operation, radwaste management, decommissioning, resource provision, and so on. Of course, the prospects of nuclear energy in Ukraine wait for discussion. However, the information already presented is more than enough to start a conversation. You can always continue the conversation if there is interest.

*The authors of the texts are solely responsible for the materials in the Blogs section. The Uatom.org editorial board may not share the opinion of the authors in the Blogs section.