Can a home miner earn enough bitcoin to offset the electricity used for heating? In a report published by PA News on November 9, 2026, at 21:49 UTC+8, a SunBit installation in a 180-square-meter home in Nokia, Finland, offered a case study—not a guarantee of free heat. The home had disconnected from district heating and was using a mining-based system instead. The report was written by CoinDesk’s Shaurya Malwa and translated by Foresight News’ Chopper.
The system directs heat from a water-cooled Bitcoin miner into stored water, which can reach 60°C, then distributes it through radiators or underfloor heating. The homeowner buys the equipment, pays for its electricity and keeps the bitcoin mined. The heat is produced while the miner runs regardless of bitcoin’s price; whether mining revenue covers the bill is a separate question.
Running costs versus installation costs
SunBit’s model for the Nokia home uses an Antminer S21 XP Hydro rated at 495 TH/s, running Braiins OS at about 5.3 kW around the clock. That implies roughly 46,400 kWh a year. At $0.11/kWh, the modeled annual electricity bill is about $5,200.
Assuming bitcoin at $82,000 and network hashrate at 1,040 EH/s, SunBit estimates annual production of about 1/12 BTC. After its optional 10% service fee, that is worth about $6,100 at the assumed price; the mining pool charges a further 0.5% fee. The resulting electricity-only surplus is approximately $900 a year. Without SunBit’s optional service, the modeled bitcoin value is about $6,800 before electricity costs. These are projections based on stated inputs, not observed results or a calculation that recovers the equipment purchase.
The report separately describes one early customer’s pool records, supplied by SunBit founder and CEO Elmeri Suomi: an S21+ Hydro rated at 358 TH/s mined 0.039 BTC over the preceding year, worth about $3,160 at the price then cited. SunBit said it could inspect data from its initial pilot customers, but not later customers’ private pool accounts.
Installation is a capital expense. One SunBit comparison puts a system at about $20,200, excluding extras, and estimates a roughly 3½-year payback against a home otherwise using 2,300 liters of heating oil annually at about $2.19 per liter. That estimate excludes maintenance and borrowing costs and assumes a modeled annual mining surplus of about $920 after electricity. Elsewhere, the report gives an installed-price range of $20,400–$31,400 and an estimated payback of three to six years. Neither estimate is a fixed return.
Heat demand and the next halving
A home cannot necessarily use all the heat a continuously running miner produces. The report says more than half can go unused, with an external dry cooler venting excess heat outdoors, particularly in summer. It also contrasts the miner’s roughly one unit of heat per unit of electricity with an air-source heat pump’s stated 2.5–3 units of heat per unit of electricity. Mining heat’s economic case therefore depends on mining revenue, not superior heating efficiency.
At the report’s publication, bitcoin was about $81,500. SunBit put its electricity-only break-even bitcoin price at roughly $70,000 after its service fee, assuming network hashrate stayed unchanged; that threshold excludes the equipment cost. A rise in competing hashrate would reduce an individual miner’s output.
The next Bitcoin halving was expected in spring 2028, when the block reward would fall from 3.125 BTC to 1.5625 BTC. Under the report’s otherwise unchanged assumptions, SunBit’s modeled mining revenue would fall from about $0.13 to $0.07 per kWh against an electricity price of $0.11 per kWh. Heat would then carry a net cost of about $0.04 per kWh. The same model puts the bitcoin price needed to continue offsetting that electricity cost at about $131,000. SunBit’s payback calculator did not account for the halving, and Suomi said the company does not promise a fixed return.
SunBit said it had delivered its first production systems in 2025 and had 30 operating installations by the time of the report, all but one in Finland. The projects described include homes and an industrial building. Their different heat needs and equipment arrangements matter: network-wide assumptions in a revenue model do not establish what any one installation will earn or how much of its heat it can use.