Bracht launches solar district heating network

Germany aims to become climate-neutral by 2045, but the small village of Bracht in central Hesse has reached that goal 20 years early. From this heating season on, over 60% of local households are now supplied with climate-neutral heat, mostly from solar energy. The project, led by the citizens’ cooperative Solarwärme Bracht eG, is unique in Europe. 

The new district heating system combines a 11,640 m² solar thermal field with a large seasonal storage basin that holds 27 million liters of water, heated up to 90 °C in summer. During winter, a heat pump raises the temperature to 70–80 °C as needed, while a wood-chip boiler provides backup heat and reduces the system’s electricity demand. A 22-meter-tall buffer tank balances daily fluctuations, and the network’s 9.7 km of pipelines now deliver renewable heat to 193 households in Bracht and Bracht-Siedlung. 

The project, developed by the University of Kassel and supported by Hesse’s state energy agency (LEA), demonstrates that decarbonizing heating in older rural housing stock can be faster and more effective than comprehensive building retrofits. It cuts CO₂ emissions by 98 % immediately upon start-up. 

Financed through €16.3 million, including €5.6 million from the European Regional Development Fund (EFRE) and €4.7 million in federal grants, the initiative relied heavily on local volunteer labor and cooperative ownership, making it a model for citizen-driven energy transition in small communities. 

Read more in the press release from LEA 

The quiet triumph of the heat pump

Once a lightning rod of political controversy, the heat pump has become a quiet success story in Germany’s energy transition. During the debates around the so-called “Heating Act” (Heizungsgesetz) of the former coalition government, the technology was criticized as too costly, impractical for older homes, or imposed by ideology. Three years later, it moved from political battleground to mainstream reality. 

According to the Federal Association of the German Heating Industry (BDH), the first half of 2025 marked a symbolic milestone: for the first time ever, more heat pumps were sold than gas boilers — about 139,500 compared with 132,500. This represents a 55% increase in heat pump sales year-on-year and a 41% decline in gas units. 

The shift is visible in cities like Duisburg, where the housing company Rheinwohnungsbau is converting an entire 1950s residential area of 776 apartments from gas to a hybrid system combining rooftop solar and central air-source heat pumps. “People told us it wouldn’t work in such old buildings,” says CEO Thomas Hummelsbeck. “We’ve proven that it does.” 

Because heat pumps operate at lower flow temperatures than gas systems, half of the buildings required insulation improvements, and about 50 % of radiators were replaced with larger surface units. The retrofits increase rent by roughly €1 per m² per month, but this is offset by reduced heating costs. Long-term, the company expects both tenants and owners to benefit from lower energy bills and greater independence from fossil fuels. 

Across the sector, however, the overall market for heating systems remains sluggish. Manufacturers like Vaillant, headquartered in Remscheid, confirm that heat pumps have become their “bestseller”, yet overall equipment sales are down 22% compared to last year. The reason, says Tillmann von Schroeter, Vaillant’s head of Germany operations, lies in ongoing policy uncertainty: “People are waiting. They’re unsure whether funding or legislation might change again. So, there’s a lot of repairing and little new investment.” 

Read more in article from tagesschau 

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