Excess heat generated from Bitcoin mining is now being used to warm up nearly 80,000 homes in Finland ahead of Christmas.
MARA Holdings Inc. announced Friday it has expanded its “district heating” project to a city of 67,000 residents in the country.
This follows a pilot program launched by the Bitcoin mining company in June this year, involving providing the recycled heat from one of its data centers to a town of 11,000 people in the Satakunta region of Finland.
This expansion is pretty significant when you take Finalnd’s overall size in mind — Mara Holdings is now heating up nearly 1.5% of all homes in Finland after all.
This initiative also aligns with Finland’s goal of reducing emissions and optimizing energy usage while providing a tangible benefit to local residents.
The country has largely moved to clean energy but 25% of homes are still powered by fossil fuels, according to Marathon advisory board member Daniel Batten.
How does district heating work? District heating systems distribute centrally generated heat — often in the form of hot water or steam — through a network of insulated pipes to buildings.
Traditionally, these systems relied on carbon-emitting fuels, raising environmental concerns. While heat recycling from traditional data centers has been explored as a sustainable alternative, these facilities often struggle with inefficiencies due to low heat output and distant locations from urban centers.
Marathon had earlier noted during pilot launch that Bitcoin mining rigs convert 95% of consumed electricity into heat, generating temperatures of 55 to 75 degrees celsius—significantly higher than the 25 to 35 degrees celsius typical of air-cooled data centers.
Bitcoin data centers are also more compact and energy-dense, which means less need of extensive pipeline infrastructure and lower heat loss in the transit, according to the miner.