Nuclear power in a clean energy system

A key source of low-carbon power

"Alongside renewables, energy efficiency and other innovative technologies, nuclear can make a significant contribution to achieving sustainable energy goals and enhancing energy security"
Fatih Birol, Executive Director, IEA


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.

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	Nuclear	Hydro	Wind	Solar	Other renewables
Nuclear	2724				
Hydro		4239			
Wind			1217		
Solar				582	
Other renewables					762
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Nuclear power has avoided about 55 Gt of CO2 emissions over the past 50 years, nearly equal to 2 years of global energy-related CO2 emissions. However, despite the contribution from nuclear and the rapid growth in renewables, energy-related CO2 emissions hit a record high in 2018 as electricity demand growth outpaced increases in low-carbon power.

	European Union	United States	Japan	Korea	Canada	Other advanced economies	Developing economies
1971	0.043	0.033	0.006	0	0.004	0.001	0.005
1972	0.096	0.079	0.013	0	0.01	0.005	0.013
1973	0.153	0.152	0.02	0	0.022	0.011	0.023
1974	0.218	0.251	0.034	0	0.034	0.018	0.044
1975	0.305	0.402	0.052	0	0.044	0.025	0.075
1976	0.404	0.571	0.075	0	0.058	0.033	0.109
1977	0.524	0.791	0.097	0	0.08	0.041	0.144
1978	0.659	1.034	0.136	0.002	0.104	0.049	0.183
1979	0.808	1.259	0.181	0.004	0.132	0.06	0.227
1980	0.982	1.483	0.233	0.007	0.163	0.073	0.283
1981	1.221	1.726	0.289	0.009	0.194	0.087	0.348
1982	1.487	1.982	0.354	0.012	0.225	0.102	0.42
1983	1.803	2.25	0.426	0.019	0.264	0.117	0.506
1984	2.202	2.548	0.508	0.029	0.305	0.136	0.618
1985	2.684	2.899	0.604	0.042	0.354	0.158	0.75
1986	3.211	3.28	0.706	0.065	0.41	0.181	0.881
1987	3.756	3.698	0.82	0.095	0.471	0.204	1.031
1988	4.338	4.182	0.928	0.125	0.536	0.225	1.197
1989	4.95	4.668	1.039	0.16	0.597	0.247	1.36
1990	5.557	5.197	1.16	0.198	0.653	0.272	1.477
1991	6.182	5.76	1.288	0.239	0.719	0.296	1.595
1992	6.811	6.329	1.422	0.279	0.78	0.321	1.712
1993	7.462	6.891	1.571	0.322	0.852	0.347	1.828
1994	8.108	7.478	1.732	0.366	0.934	0.374	1.951
1995	8.761	8.093	1.907	0.417	1.007	0.403	2.078
1996	9.44	8.716	2.087	0.471	1.078	0.433	2.216
1997	10.115	9.294	2.277	0.526	1.141	0.464	2.355
1998	10.781	9.909	2.473	0.591	1.194	0.495	2.49
1999	11.445	10.573	2.661	0.665	1.25	0.525	2.624
2000	12.121	11.254	2.852	0.745	1.304	0.554	2.772
2001	12.809	11.925	3.042	0.829	1.361	0.583	2.918
2002	13.492	12.606	3.22	0.924	1.418	0.612	3.078
2003	14.184	13.276	3.364	1.026	1.474	0.641	3.26
2004	14.88	13.961	3.535	1.126	1.54	0.668	3.448
2005	15.562	14.638	3.722	1.238	1.606	0.693	3.632
2006	16.239	15.312	3.905	1.35	1.674	0.722	3.826
2007	16.873	15.995	4.064	1.456	1.74	0.749	4.033
2008	17.488	16.68	4.218	1.571	1.807	0.776	4.324
2009	18.072	17.344	4.384	1.686	1.869	0.803	4.608
2010	18.672	18.013	4.556	1.798	1.929	0.825	4.905
2011	19.279	18.659	4.614	1.912	1.99	0.851	5.231
2012	19.813	19.235	4.623	2.024	2.043	0.875	5.55
2013	20.331	19.833	4.629	2.123	2.101	0.9	5.869
2014	20.83	20.433	4.628	2.235	2.158	0.923	6.202
2015	21.286	20.992	4.629	2.349	2.206	0.936	6.523
2016	21.692	21.535	4.63	2.456	2.25	0.938	6.828
2017	22.063	22.072	4.637	2.55	2.289	0.932	7.119
2018	22.40	22.58	4.64	2.65	2.32	0.92	7.38
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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.

	Less than 10 years	10-30 years	Over 30 years
United States	1	8	90
European Union	0	17	83
Russia	25	14	61
Japan	2	53	45
Korea	24	48	28
India	40	45	16
China	80	20	0
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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.

Read more about extensions in…

  • United States
  • European Union
  • Japan

In the United States, some 90 reactors have operational licenses through 60 years, yet several have already retired early, and many more are at risk due to relatively low wholesale electricity prices.

	Nuclear	Renewables	Fossil fuels
New	100	0	0
Lifetime extension	43	0	0
Solar PV	0	50	0
Onshore wind	0	50	0
Offshore wind	0	105	0
Supercritical coal	0	0	75
Combined cycle natural gas	0	0	65
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In the European Union, the case for nuclear lifetime extensions is stronger. The economic case remains compelling even if the decrease in wind and solar PV costs accelerates.

	Nuclear	Renewables	Fossil fuels
New	110	0	0
Lifetime extension	43	0	0
Solar PV	0	85	0
Onshore wind	0	90	0
Offshore wind	0	90	0
Supercritical coal	0	0	145
Combined cycle natural gas	0	0	120
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Nuclear extensions are an even more competitive in Japan, where renewables remain expensive and coal and gas must be imported.

	Nuclear	Renewables	Fossil fuels
New	105	0	0
Lifetime extension	43	0	0
Solar PV	0	130	0
Onshore wind	0	150	0
Offshore wind	0	125	0
Supercritical coal	0	0	95
Combined cycle natural gas	0	0	105
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The Nuclear Fade Case


Given these challenges, there is a possibility that the nuclear fleet in advanced economies could face a steep decline. The IEA’s Nuclear Fade Case explores what could happen over the coming decades in the absence of any additional investment in lifetime extensions or new projects.

Under this case, nuclear capacity operating in advanced economies would decline by two-thirds by 2040, from about 280 GW in 2018 down to just over 90 GW in 2040. The European Union would see the largest decline with the share of nuclear in the generation mix falling to just 4%. The share in the United states would drop from to 8%, and in Japan the share would fall to 2% - well below their 2030 target of 20-22%.

	European Union	United States	Japan	Other advanced economies
2018	125.4	104.1	9.1	43.7
2020	119.5	98.5	13.3	44.4
2025	70.5	93.8	14.7	41.9
2030	44.5	84.3	14.7	30.8
2035	25.6	62.5	8.6	25.6
2040	20.5	46.6	2.8	23.5
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	Sustainable Development Scenario	SDS with nuclear fade
2019	1228	1228
2020	1385	1386
2021	1536	1545
2022	1687	1709
2023	1842	1885
2024	2000	2084
2025	2170	2309
2026	2355	2558
2027	2553	2831
2028	2758	3122
2029	2969	3427
2030	3185	3742
2031	3397	4054
2032	3598	4348
2033	3794	4631
2034	3987	4905
2035	4176	5169
2036	4362	5425
2037	4548	5675
2038	4734	5919
2039	4918	6160
2040	5100	6401
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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.

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