VANCOUVER – 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, according to a new report by the International Energy Agency.

Nuclear is the second-largest low-carbon power source in the world today, accounting for 10% of global electricity generation. It is second only to hydropower at 16%. For advanced economies – including the United States, Canada, the European Union and Japan – nuclear has been the biggest low-carbon source of electricity for more than 30 years and remains so today. It plays an important role in electricity security in several countries.

However, the future of nuclear power is uncertain as ageing plants are beginning to close in advanced economies, partly because of policies to phase them out but also as a result of economic and regulatory factors. Without policy changes, advanced economies could lose 25% of their nuclear capacity by 2025 and as much as two-thirds of it by 2040, according to the new report, Nuclear Power in a Clean Energy System.

The lack of further lifetime extensions of existing nuclear plants and new projects could result in an additional 4 billion tonnes of CO2 emissions.