Emissions fell by 1.5 percent in 2025 from the previous year, according to a study by Agora Energiewende, compared to a three-percent drop in 2024 and 10 percent the year before that.

"At the current rate of reduction, there will still be a climate protection gap with regard to 2030," said the study.

By 2030, Germany aims to reduce its emissions by 65 percent compared to 1990 levels.

To achieve its goals, Germany will have to cut its emissions four times faster than it did last year from 2026 onwards, Agora warned.

Last year's emissions cuts were driven by falls in energy-intensive industries, many of which are struggling as the economy stagnates, and record solar power generation.

But emissions in transport and buildings rose again in 2025, noted the study, criticising "years of insufficient progress" in the shift to electric vehicles and heat pumps.

When burned, fossil fuels emit greenhouse gases such as carbon dioxide that trap heat near the Earth's surface, contributing to climate change.

"Wind and solar energy will remain the backbone of Germany's energy transition," said Julia Blaesius, director of Agora Energiewende Germany.

"However, the power sector -- up till now the workhorse of emissions reduction -- cannot permanently offset the shortcomings in switching to climate technologies in transport and buildings."

- Merz under fire -

The news is likely to raise fresh questions about whether green policies are being undermined by the government of conservative Chancellor Friedrich Merz, who took power last year.

His coalition has championed a series of policies that critics claim could damage the fight against climate change, but which Merz says are needed to reduce burdens on businesses and households.

He led criticism of an EU plan to ban new combustion-engine car sales from 2035, which was subsequently watered down, and his coalition is moving to scrap an unpopular law that required newly installed heating systems to run on mostly renewable energy.

His economy minister, a former energy executive, has proposed scrapping some solar energy subsidies and building new gas-fired power stations.

Overall Germany's 2025 emissions totalled 640 million tonnes, a reduction of nine million tonnes from the previous year, according to Agora.

National emissions are down 49 percent from 1990 levels.

The energy sector however contributed fewer reductions in 2025 than in previous years due to weather conditions -- there was insufficient wind earlier in the year.

In buildings, fossil fuel consumption for heating increased due to a cold start to the year, raising emissions in this area by over three percent compared to 2024, Agora said.

Higher fuel consumption pushed transport emissions up by 1.4 percent compared to 2024.

There were signs of positive momentum, however.

Around 300,000 heat pumps were sold last year, passing gas boilers for the first time.

The share of new EV registrations rose sharply from a year earlier, accounting for about a fifth of all vehicles sold, the study said, although the sector was recovering from a dire year in 2024.

However the think tank warned that "persistently high investment costs continue to slow the ramp-up of electric technologies in industry, buildings, and transport".