What a winter with a heat pump costs

A well-insulated 150 m² house with underfloor heating uses around 3,500 kWh of electricity over a whole winter with a heat pump. At 1.35 lei/kWh that is about 4,700 lei a year, slightly less than the same heat would cost on gas. On radiators at 55 °C the same house uses 30% more, and unless your electricity contract is cheap, the heat pump ends up costing more than gas.

Below are the full calculations for 100, 150 and 200 m² houses, with every number shown so you can redo them for your own home. They are the same numbers the calculator on our sizing page uses.

How we work out consumption, in three steps you can check

No rules of thumb and no hand-picked bills. The calculation is three multiplications, and every figure has a source.

1. Heat the house needs in a year = heating output (kW) × equivalent full-load hours per year.
2. Electricity used by the pump = heat ÷ SCOP, the pump's average efficiency over the season.
3. Cost = electricity × the price per kWh in your contract.

Heating output comes from floor area and insulation. For a two-storey house with 2.6 m ceilings we use 55 W/m² if it is well insulated, 75 W/m² for average insulation and 100 W/m² if it is poorly insulated. The 55 is not a guess: it is the average of the coverage we publish for each model, from 4 kW for up to 70 m² to 16 kW for 300 m². How to find the right output is covered in How to choose the output of a heat pump.

Equivalent hours are how long the pump would have to run flat out to deliver a year's heat. We take them from the heating degree days Eurostat publishes for Romania (dataset nrg_chdd_a, base 18 °C), averaged over 2021–2025: 2,718.8 degree days. For climate zone II, where the design outdoor temperature is −15 °C (Oradea, Arad, Bucharest):

24 × 2,718.8 ÷ (18 − (−15)) = 24 × 2,718.8 ÷ 33 = 1,977 hours, rounded to 1,980 hours a year.

For the pump we use the Heat Pump KEYMARK certified SCOP of the Chofu R290 10 kW Premium: 4.68 at 35 °C (underfloor) and 3.61 at 55 °C (radiators). These were tested by an independent lab (SGS), not declared by the manufacturer; certificates can be checked at heatpumpkeymark.com. The other models have similar SCOP values, listed on each product page.

Heat pump consumption for 100, 150 and 200 m² houses

Well-insulated houses (55 W/m²), ground floor plus one storey, climate zone II. Space heating only, no hot water. Electricity prices are the two offers in our calculator: 1.35 lei/kWh (PPC Fix Online, September 2026) and 1.11 lei/kWh (Hidroelectrica Viitor Hidro, Muntenia, 01.07–30.09.2026), both including 21% VAT.

To see where a row comes from, take the 150 m² house: 150 × 55 ÷ 1,000 = 8.25 kW. 8.25 kW × 1,980 h = 16,335 kWh of heat a year. Divided by SCOP 4.68, that is 3,490 kWh of electricity. Multiplied by 1.35 lei, 4,712 lei a year.

How much does an 8 kW, 12 kW or 16 kW heat pump use?

There are two answers, and they are worth keeping apart.

The first is instantaneous draw, what the unit pulls from the grid at full output. From the datasheets, at +7 °C outside and 35 °C flow: the 8 kW Standard draws 1.70 kW, the 12 kW Standard 2.45 kW and the 16 kW (R32) 3.72 kW. One kilowatt of electricity for four to five kilowatts of heat.

The second is yearly consumption, and here the pump's size matters little. The house decides consumption, not the label on the unit. A pump does not run flat out all the time; for much of the winter it runs at reduced speed. In the examples above, the 150 m² well-insulated house needs 8.25 kW, gets an 8 kW pump and uses around 3,500 kWh a year. The 200 m² house needs 11 kW, the right pump is 12 kW, and consumption is around 4,650 kWh.

For 16 kW, take a house that needs 15 kW (200 m² with average insulation, or 150 m² poorly insulated): 15 × 1,980 = 29,700 kWh of heat. With the 16 kW R32 model's own datasheet SCOP of 4.5 at 35 °C, that is 6,600 kWh of electricity, or 8,910 lei at 1.35. On radiators, with SCOP 3.2 at 55 °C, 9,281 kWh. The full picture for 250–300 m² houses is in the article on the 16 kW heat pump.

Heat pump vs gas boiler, pellets and wood

To compare different systems fairly, look at the price of one kWh of heat delivered into the house: the fuel price divided by the seasonal efficiency. Same prices as in our calculator, checked on 17.09.2026:

• Gas: 280.38 lei/MWh incl. VAT (Distrigaz Sud, final price table from 01.07.2026), i.e. 0.28 lei/kWh. Condensing boiler, 92% efficiency.
• ENplus A1 pellets in bags: 2,166.60 lei/tonne at 4.6 kWh/kg, i.e. 0.471 lei/kWh. 75% efficiency, the minimum for new boilers under Regulation (EU) 2015/1189.
• Dry beech firewood (20% moisture): 350 lei per stacked cubic metre delivered, at 1,885 kWh each, i.e. 0.186 lei/kWh. Same 75%, for a new boiler.
• Direct electric heating: 100% at the point of use (Regulation (EU) 2015/1188).

Put plainly: against gas, the heat pump on underfloor heating wins, but only just, 0.29 against 0.30 lei per kWh of heat with electricity at 1.35. With a 1.11 lei offer the gap becomes real, about 1,100 lei a year for the 150 m² house. On radiators at 55 °C with electricity at 1.35, gas is cheaper. Against pellets and direct electric heating the heat pump wins clearly in every case. Beech wood stays cheap as a fuel, if you leave out the work, the storage, and the fact that an old stove is far less efficient than a new boiler.

You can work out the break-even yourself. A kWh of heat from gas costs 0.28 ÷ 0.92 = 0.304 lei. The heat pump matches it when electricity costs 0.304 × SCOP: 0.304 × 4.68 = 1.42 lei/kWh on underfloor and 0.304 × 3.61 = 1.10 lei/kWh on radiators. Below those prices, the heat pump's bill is lower than gas. What you gain or lose over 15 years, investment included, and what changes in the house are worked out in the article on a heat pump instead of a gas boiler.

What pushes the bill up or down

Insulation

This is the biggest factor, because it changes how much heat the house needs. The same 150 m² house, electricity at 1.35:

The difference between the well and poorly insulated house is almost 3,900 lei a year, every year, and the poorly insulated house also needs a bigger, more expensive pump. If you are planning to insulate anyway, do it before the heat pump, not after.

Flow temperature

The cooler the water sent into the system, the easier the pump's job. SCOP 4.68 at 35 °C against 3.61 at 55 °C means 4.68 ÷ 3.61 = 1.30: 30% more electricity for the same heat, purely because of temperature. Underfloor heating works at around 35 °C; radiators need more, how much depends on how large they are for the room. The R290 range reaches 75 °C flow and runs on existing radiators, but efficiency drops at high temperatures. Check whether your radiators can cope with cooler water; sometimes one larger radiator in the coldest room solves it. The heating curve in the controller works the same way: set too high "to be safe", it costs money all winter without any difference you would feel.

Your electricity tariff

Romania's electricity market has been fully liberalised since 1 July 2025, so there is a range of prices rather than one. Our calculator has three offers, all with VAT: 1.11, 1.35 and 1.69 lei/kWh (PPC Simplu Online, 12 months). For the 150 m² house on underfloor heating, that is 3,874, 4,712 or 5,899 lei a year for exactly the same heat. The spread, over 2,000 lei, is bigger than the gap between heat pump and gas. Check the price actually on your bill and compare offers on ANRE's comparison tool. If you have solar panels, you produce part of this electricity yourself; how much, month by month, is worked out in the article on heat pumps and solar panels.

Night setback and scheduling

With a gas boiler, people often turn the temperature down a lot at night. With a heat pump on underfloor heating the saving is small: the screed cools and warms slowly, and in the morning the pump has to catch up fast with hotter flow water, exactly where its efficiency is weakest. A small night setback makes sense; a large one usually does not. The thermostat controller included with every pump in the range lets you set schedules; the right settings for your house are made at commissioning.

What the calculation leaves out

• Domestic hot water. We counted space heating only; hot water adds the same to every system, so it does not change the ranking.
• Equipment and installation prices, which vary a lot from house to house. Each model's price is on its page in the catalogue, and installation is quoted on site; see how we work on the installation page.
• Servicing and labour: gas boiler checks, the chimney, ash, carrying wood. The heat pump also needs an annual service to keep the warranty (3 years on the unit, 5 years on the compressor; details on the warranty page).
• The heat pump can cool in summer through the same system, but that cost is not in the figures above.

Frequently asked questions

How much does a 16 kW heat pump use in a year?

That depends on the house, not the pump. In a house needing 15 kW, climate zone II, underfloor heating: around 6,600 kWh of electricity a year, or 8,910 lei at 1.35 lei/kWh. On radiators at 55 °C, around 9,300 kWh. At full output, at +7 °C outside, it draws 3.72 kW from the grid.

Heat pump or gas boiler: which gives the lower bill?

On underfloor heating, the heat pump, but at 1.35 lei electricity the margin is small (0.29 against 0.30 lei per kWh of heat). On radiators at 55 °C, gas, unless you pay less than about 1.10 lei/kWh for electricity. The heat pump also cools in summer and needs no chimney, but that does not show on a winter bill.

Is a heat pump worth it with radiators?

Yes, if you can lower the flow temperature. At 55 °C the yearly cost is 30% higher than on underfloor heating. Radiators that are large for their rooms work fine with cooler water for most of the winter; we check this room by room before quoting.

Why are your figures higher than what others quote?

Because we do not subtract solar and internal gains, for which we have no sourced factor. We prefer an upper estimate you can check to one that looks good and that you cannot reproduce.

Does my climate zone matter?

Yes. These figures are for zone II (Oradea, Arad, Bucharest, −15 °C). In zone III (Cluj, Sibiu, Iași, −18 °C) a house needs more kilowatts and more heat per year, so consumption rises. Chofu heat pumps operate down to −20 °C outside.

Work it out for your house

On the sizing page you enter floor area, insulation, windows and heating type, and the result shows both the right output and the yearly cost against gas, pellets or wood, at your own tariff. If you would rather go straight to a quote including installation, send us your house details.