Solar power boom keeps Germany’s 2025 renewable electricity share stable

The fast growth of solar PV capacity in Germany helped keep the country’s share of renewable energy in the electricity grid stable at 55.9 percent in 2025, an analysis by the research institute Fraunhofer ISE has shown. Solar power output grew by 21 percent over the year and fed 71 terawatt hours (TWh) into the public grid, meaning the renewable energy source surpassed lignite-fired power generation (67 TWh) for the first time.

With a gross output of 132 TWh, wind power remained the largest renewable electricity source. However, weak wind conditions cut the wind turbines’ output by 3.2 percent compared to the previous year. Biomass plants fed just over 36 TWh into the grid, while hydropower installations, which grappled with low precipitation, fed just under 18 TWh. The country’s total renewable power output, including geothermal energy, amounted to 278 TWh, of which 256 TWh were fed into the grid and 22 TWh were used to run the installations themselves, Fraunhofer ISE said.

While total renewable power output grew by 6 TWh, it still fell well short of the 2025 net target of 346 TWh. This was mainly due to the sluggish expansion of onshore and offshore wind power, where 4.5 gigawatts (GW) and 0.29 GW of new capacity were installed, respectively. The total installed capacity of about 68 GW was still well below the target of 76.5 GW.

Moreover, a high share of self-consumption from solar PV installations, and the more grid-friendly but less productive orientation of many newly installed solar panels, also had a reducing effect on the renewable energy share in the grid. By orienting the panels towards the east or the west, they help to stabilise the grid in the morning and the evening but miss the most intensive sunshine hours during midday. Installed module capacity grew by about 16 GW to nearly 117 GW, but according to the institute, Germany will need to add 22 GW in 2026 to stay on course for its climate targets.

Across Europe, solar power production tripled in the past decade, while coal-fired power production receded by 60 percent. However, while Germany’s net output of lignite plants was cut by nearly 4 TWh in 2025, fossil electricity production rose slightly, as hard coal and fossil gas output increased.

The research institute noted that rapid growth of electricity storage capacity to a total of 25 gigawatt hours (GWh) was made possible by lower costs and potential profits through stabilising electricity prices. Fraunhofer ISE said the required capacity for 2030 would be in the range of 100 to 170 GWh. According to researcher Leonhard Gandhi, especially the rise of industry-scale storage units looks set to “fundamentally transform the functioning of Germany’s electricity system.”