Calculators
Heat pump
City, floor area, insulation and heating — and right away the heat pump size, the heat over a year and the price of a year of heat: gas, an electric boiler, an air-source and a ground-source heat pump. For cities in Vietnam — hot water.
What you get
- —heat loss in a hard frost
- —heat pump
- —heat and hot water per year
- —coldest five days · heating season
- —air-to-water heat pump, equipment only
- —gas price for heating
- —for hot water per year
A year of heat: what it costs
What the calculation assumes
- Heat losses: passive house 0.25, new 1.0, average 1.8, old 2.8 W per m² per degree — 11, 45, 81 and 126 W per m² at −25 °C.
- Heat from people, appliances and the sun covers about 10% of the losses.
- Hot water — 50 l a day per person at 55 °C, plus 20% for losses.
- Gas: 9.19 kWh per m³ (7,900 kcal), boiler efficiency 92%; the gas price is checked for Moscow, Saint Petersburg, Krasnodar Krai and Tatarstan — for other cities, enter your own.
- The default price per kWh is the tariff for homes with electric stoves and electric heating where it is known; otherwise, the region’s base tariff.
- The heat pump’s seasonal factor is a share of the Carnot limit: 45% for air (the evaporator 5 °C colder than the season’s average temperature), 50% for ground (brine at about 0 °C). This is a model, not a test.
- Heat pump — the nearest size no smaller than 90% of the heat loss in a hard frost; in severe frost — top-up heating.
Climate — our calculation from hourly data for 2005–2023: PVGIS © European Communities, 2001–2026; ERA5, Copernicus Climate Change Service.
Do the numbers add up?
Send them with a request — we’ll check on site and draw up an estimate.