Finnish company SunBit operates 30 Bitcoin Boilers that use bitcoin mining computers to heat homes, commercial buildings and industrial sites. SunBit CEO Elmeri Suomi said all but one of the systems are in Finland. The machines convert mining electricity into heat, producing water of up to 60°C for radiators and floor heating while allowing owners to keep the bitcoin earned through mining. Installation costs roughly $20,000 or more, and returns depend on bitcoin’s price, electricity costs and mining competition. Bitcoin’s next halving, expected in spring 2028, will cut the mining reward by half and could lengthen payback periods. The systems have replaced or supplemented gas, oil, wood and district heating, while larger waste-heat projects in Finland include MARA systems serving district-heating networks for about 80,000 residents.