The world could keep more than two-fifths of its electricity low-carbon.
Renewable and nuclear generation reached about 43% in 2025; the test is whether that share survives another year.
Good outcome probability
Renewables and nuclear combined will contribute at least 40% of global electricity generation in 2026.
There is a difference between installing clean technology and using it at scale. The share of global power actually generated without direct fossil-fuel combustion shows how much of the electricity system those technologies are serving.
In its Global Energy Review 2026, the International Energy Agency estimated that renewable and nuclear sources supplied 43% of the world's electricity in 2025. The agency separately expects renewable generation to grow by more than 8% in 2026. Against that backdrop, our editorial forecast is that the low-emissions share does not fall below 40%.
Forty percent is not a climate-safety threshold or proof that total power-sector emissions are falling. Electricity demand, the mix of fossil generation and industrial emissions all matter. Nonetheless, retaining the share during rising demand would demonstrate how established low-emissions electricity has become.
What this could mean.
- Why this could be good
- Low-emissions generation reduces exposure to fuel combustion but does not, alone, ensure declining global emissions.
- Potential positive outcomes
The transition could become more resilient to demand growth.
Grid flexibility and transmission investments may become urgent.
Poor hydro conditions could temporarily increase dependence on coal or gas.
The assessment.
- What we are forecasting
- Renewables and nuclear combined will contribute at least 40% of global electricity generation in 2026.
- Time horizon
- Full calendar year 2026, using the IEA's published generation mix.
- Editorial confidence in the evidence: 98%
- The IEA puts the 2025 low-emissions share at 43%, and forecasts further renewable electricity growth in 2026.
- What could change the outcome
- Hydropower droughts, nuclear outages, rapidly rising total demand and changes to data methodology could lower the share.
The evidence.
- Global Energy Review 2026 — Electricity supply ↗International Energy Agency · 2026
- Electricity Mid-Year Update 2026 — Executive summary ↗International Energy Agency · 2026