Bitcoin miners’ waste heat is warming homes in Finland, but according to SunBit’s calculations, Bitcoin needs to reach about $131,000 after the 2028 halving to cover the cost of electricity.
30 of the systems developed by Finnish company SunBit are operating. One home in the town of Nokia, with 180 square meters of floor space, has also disconnected from the district heating network and is being heated with heat from a mining device. SunBit founder and CEO Elmeri Suomi told CoinDesk that all but one of the systems are located in Finland.
The device converts the electricity it uses for mining into heat. SunBit transfers this heat to radiators and underfloor heating pipes using water; as long as the device is running, it also produces Bitcoin. When the revenue generated can cover the electricity bill, there is no additional energy cost for heating.
The calculations change if Bitcoin falls below $70,000
In SunBit’s example calculation, a device that uses 5.3 kilowatts of electricity per hour consumes about 46,400 kilowatt-hours per year. At an electricity price of 11 cents per kilowatt-hour, that amounts to about $5,200 in annual expenses. Using specific assumptions for the Bitcoin price and the network’s total hashrate, the company estimates that mining revenue would cover the cost of electricity at a threshold of just under $70,000. This threshold does not include the installation cost, which starts at about $20,000.
SunBit’s calculations assume a Bitcoin price of about $82,000 and a network hashrate of 1,040 exahashes per second. Under these conditions, the device is expected to produce about one-twelfth of a Bitcoin per year. After the company’s service fee is deducted, the owner could be left with about $900 in revenue above the electricity bill. However, if more miners join the network, the revenue per device may decline.
Heat pumps provide 2.5 to 3 kilowatt-hours of heat for every kilowatt-hour of electricity they use. A mining device, by contrast, converts electricity into heat on a one-to-one basis; its economics rely not on heating more efficiently, but on Bitcoin revenue covering the cost of electricity.
The 2028 halving raises the threshold
The halving expected in spring 2028 will reduce the amount of new Bitcoin awarded per block from 3.125 BTC to 1.5625 BTC. Holding SunBit’s current calculation inputs constant, mining revenue falls from about 13 cents to 7 cents per kilowatt-hour. That is below the 11-cent electricity price used by the company.
According to SunBit, after the halving, Bitcoin would need to reach about $131,000 for the cost of electricity to be covered again. SunBit estimates the installation cost of the systems at about $20,400 to $31,400 and the payback period at three to six years—longer than the time until the 2028 halving.
Not investment advice.