World Nuclear Performance Report 2021 COP26 Edition


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Director General's Preface

This is a special edition of the World Nuclear Performance Report, released for COP26, taking place in Glasgow between 31 October - 12 November 2021. In the run-up to COP26 we saw growing political commitment to achieving net zero greenhouse gas emissions by the middle of this century. Anything less will mean failing to meet the goals set in the Paris Agreement.

New analysis in this edition shows that since 1970 nuclear reactors have avoided the emission of 72 billion tonnes of carbon dioxide, compared to the emissions that would have arisen had coal-fired generation been used instead.

The UK COP Presidency has led the global call for an end to coal-fired generation, and this commitment should apply to all fossil-fuelled generation.

Soaring fuel costs and geopolitical scarcity are having devastating consequences for domestic, business and industry users alike, consequences that are particularly hard when many countries are trying to rebuild their economies after the COVID pandemic.

While gas may be not as polluting as coal, it is still a large source of carbon dioxide and methane emissions. Only a fully decarbonized electricity generation mix, supplied by nuclear energy working together with hydropower and other renewables, will set the world on a fast track to net zero.

The IPCC recently published the first part of its Sixth Assessment Report. This report confirmed what we have known for many years - global greenhouse gas emissions need to fall fast if we are to have any chance of limiting the effects of climate change to manageable levels.

More than half of the reactors permanently shut down in the last few years have done so not because of technical limitations, but because of political phase-out policies or the failure of markets to adequately recognize the value of on-demand, low-carbon, reliable nuclear power. This is a loss of low-carbon generation that the world can ill-afford to squander.

At the end of 2020 there were 441 operable nuclear reactors, with a combined capacity of 392 GWe. In total, nuclear reactors generated 2553 TWh of electricity worldwide in 2020, helping to avoid the emission of two billion tonnes of carbon dioxide, which would have been produced if that electricity had been generated from coal-fired power plants.

Despite some reactors curtailing generation to account for reduced demand or to offer load-following services, the global capacity factor in 2020 was still high at 80.3%, down from 83.1% in 2019, but maintaining the high performance seen over the last 20 years.

The total capacity of operable nuclear power plants has remained almost unchanged for the last three years. In 2020, five new reactors started up, but this was countered by the closure of six reactors. Between 2018 and 2020 there have been 26 reactors permanently shut down with a total capacity of 20.8 GWe, compared to 20 new reactors starting up, with a total capacity of 21.3 GWe.

It is vital that the contribution made by nuclear generation increases to help reduce greenhouse gas emissions from fossil fuels. In addition to its enormous contribution to low carbon electricity generation, nuclear energy can also produce low-carbon heat, which offers enormous opportunities to decarbonize other hard-to-abate sectors of the economy, such as hydrogen production, heating and cooling of buildings, industrial processes, fresh water production, transport and shipping. The operation of the existing nuclear fleet must be extended as long as feasible, and the pace and scale of new nuclear construction must increase.


Sama Bilbao y León
Director General
World Nuclear Association

29 October 2021 


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