IEA Revises Down Global Solar Growth Outlook for 2025–2030

The International Energy Agency (IEA) has trimmed its forecast for renewable energy growth between 2025 and 2030 by around 5%, attributing the adjustment mainly to lower-than-expected solar capacity additions. Despite the downgrade, solar PV remains the dominant force, projected to contribute nearly 80% of the 4.6 TW of total renewable capacity expected to be added worldwide over the period.

According to the IEA’s Renewables 2025 report, around 3.6 TW of new solar capacity is anticipated globally by the end of the decade. The agency expects 2025 to mark another record year, with close to 600 GW of new solar installations — driven largely by distributed solar systems. Growth is predicted to moderate slightly through 2026–2028, before rebounding strongly toward 600–700 GW per year in 2029–2030.

Forecast Revision and Regional Trends

Compared to last year’s outlook, the IEA’s latest projections represent a 248 GW reduction in total renewable additions. More than 70% of this downgrade stems from solar, especially utility-scale PV, with the most significant cuts in China and the United States.

China’s forecast has been reduced by about 129 GW, while the U.S. outlook has dropped by 140 GW, affected by factors such as FEOC restrictions, federal land permitting delays, and the pending expiration of residential solar tax credits. The U.S. residential market is expected to feel the sharpest impact.

Meanwhile, several regions have moved in the opposite direction. The European Union has seen a modest upgrade, led by growth in Germany, Spain, Italy, and Poland, while India’s renewable forecast is up nearly 10% across all technologies. The Middle East and North Africa region has also seen a major uplift of about 23%, driven by rapid solar expansion in Saudi Arabia and other emerging markets.

Overall, the IEA notes that four out of five countries are on track to deploy renewable power faster in 2025–2030 than in the previous five-year period. Saudi Arabia, Pakistan, and several Southeast Asian nations are highlighted as key drivers of new solar growth.

Solar to Lead Global Power Mix

By the end of the decade, renewables are projected to become the largest source of global electricity, supplying about 43% of total generation. Solar PV is set to overtake hydropower as the single largest renewable contributor by 2030.

The IEA expects total renewable electricity generation to reach around 16,200 TWh in 2030 — roughly 850 TWh lower than the previous year’s forecast, reflecting the reduced capacity outlook and rising levels of curtailment in solar and wind generation.

Infrastructure and Integration Challenges

The agency warns that increasing curtailment and periods of negative electricity prices underscore the urgent need for grid modernization, storage capacity, and flexible generation. While several countries have started responding through capacity and storage auctions, the IEA emphasizes that much greater investment will be essential to integrate the accelerating wave of variable renewables efficiently and securely.

Global Outlook Beyond 2030

Complementary analyses by GlobalData project that total global solar capacity could still surpass 4.8 TW by 2030 and reach nearly 7.6 TW by 2035, suggesting that while short-term forecasts have softened, the long-term trajectory for solar remains firmly upward.