Geothermal Heat Pumps: Higher Upfront Cost, Lower Bills Over 20 Years
Berlin – September 15, 2026 -- Homeowners weighing a heating system upgrade are being pointed underground, as geothermal heat pumps promise lower long-term costs despite steeper installation prices. A new short study by consulting firm Prognos, commissioned by the Bundesverband Geothermie, the Erdwärmegemeinschaft Bayern, and the Bundesverband Wärmepumpe (BWP), finds that ground-source systems can undercut air-source heat pumps by roughly 8 percent in total annual costs over a 20-year period.
Ground temperatures stay near 10 degrees Celsius year-round
In Central Europe, subsurface temperatures remain relatively constant at around 10 degrees Celsius throughout the year. This narrow gap between the heat source and the heating system keeps operating conditions favorable even in winter, translating into consistently lower running costs.