According to the IEA’s Monthly Electricity Statistics, total net electricity generation in the OECD reached 860.6 TWh in May 2025. Of this total, 356.6 TWh (41.4%) came from fossil fuels, 358.5 TWh (41.7%) from renewable sources, and 141.6 TWh (16.5%) from nuclear energy. In the first five months of 2025, total net electricity output increased by 2.3% compared to the same period in 2024.

Renewable generation recorded a 6.0% year-on-year increase (+20.2 TWh), driven mainly by solar and wind power. Solar output rose sharply by 20.7% (+19.0 TWh), continuing its sustained upward trend, while wind generation grew by 8.4% (+7.0 TWh), boosted in particular by OECD Europe (+20.3% year-on-year, +7.1 TWh) with notable increases in Germany (+1.8 TWh), the United Kingdom (+1.6 TWh) and Sweden (+1.1 TWh). These gains helped renewables edge ahead of fossil fuels as the main source of electricity in the OECD in May.

In contrast, fossil fuel-based generation fell by 4.8% year-on-year, with natural gas accounting for 26.4% of total generation, coal for 13.4% and oil for 1.1%. Gas-fired generation decreased by 6.3% (-15.4 TWh), with declines across all OECD regions: OECD Americas (-5.9%, -10.1 TWh), OECD Asia-Oceania (-11.0%, -4.0 TWh) and OECD Europe (-3.7%, -1.3 TWh). Coal-fired generation fell slightly by 1.3% (-1.6 TWh), with a sharp drop in OECD Europe (-12.0%, -3.0 TWh) offsetting increases in the OECD Americas (+1.7%, +1.0 TWh) and OECD Asia-Oceania (+1.2%, +0.4 TWh). Cumulatively in 2025, natural gas generation has declined by 0.6% (-7.1 TWh), while coal generation has risen by 6.2% (+40.1 TWh).

Nuclear generation in the OECD decreased by 1.0% (-1.4 TWh) in May, with output rising in OECD Asia-Oceania (+6.8%, +1.6 TWh) but falling in OECD Europe (-4.2%, -2.0 TWh) and OECD Americas (-1.3%, -1.0 TWh). However, in cumulative terms for 2025, all regions have increased nuclear output: OECD Asia-Oceania by 14.1% (+15.1 TWh), OECD Europe by 1.9% (+5.1 TWh) and OECD Americas by 0.2% (+0.6 TWh).

Among the month’s most notable milestones, Hungary recorded an all-time low in coal-fired generation, producing just 82.0 GWh—equivalent to 2.5% of its total electricity output—compared to 9.1% in December 2023.

The IEA’s Monthly Electricity Statistics provide data on electricity production and trade for all OECD member countries, as well as generation figures for selected other economies. Access to the full dataset now requires an IEA account, which can be created via the agency’s website.