How a heat pump works
A heat pump does not generate heat by burning fuel. It moves heat from one place to another using a refrigeration cycle — the same physics that makes a refrigerator cold on the inside by expelling heat from its back. In heating mode, the pump extracts low-grade thermal energy from the outdoor air, the ground, or groundwater, concentrates it using a compressor, and delivers it into the building at a usable temperature.
The key performance metric is the Coefficient of Performance (COP): the ratio of heat output to electrical energy consumed. A heat pump with a COP of 3.5 delivers 3.5 kWh of heat for every 1 kWh of electricity used. A gas boiler, by comparison, converts at most 0.95 kWh of heat per kWh of gas input — and gas carries a higher carbon intensity per unit of energy than the Polish electricity grid, which has been decarbonising progressively since 2019.
The three main types
Air-source heat pumps (ASHP)
Air-source units extract heat from outdoor air. They are the most widely installed type in Poland because they require no ground works: the outdoor unit sits on a concrete pad or wall bracket, and the indoor unit connects to the heating distribution system. Installation is typically completed in one to three days.
Modern ASHPs operate down to outdoor temperatures of −20°C or lower, though COP drops at low temperatures. At −10°C, a well-designed ASHP might deliver a COP of 1.8–2.2; at +7°C (the European standard test condition A7/W35), the same unit might reach 3.5–4.5. Seasonal performance is usually expressed as the Seasonal Coefficient of Performance (SCOP), which accounts for the full heating season. For the Polish climate, SCOP values for quality ASHP systems currently range from about 2.8 to 3.6.
Ground-source heat pumps (GSHP)
Ground-source (geothermal) pumps extract heat from the soil via a loop of pipe buried horizontally (requiring significant land area) or vertically (via boreholes drilled to 60–150 m depth). Because ground temperature below the frost line stays relatively stable year-round (8–12°C in most of Poland), GSHPs achieve higher and more consistent SCOPs than ASHPs — typically 3.5–5.0 in Polish conditions.
The trade-off is installation cost. A borehole GSHP system for a family home in Poland typically costs 50,000–90,000 PLN, compared to 25,000–45,000 PLN for an equivalent ASHP installation. Drilling permits and geological conditions (rock type, groundwater depth) add planning complexity.
Water-source heat pumps
These systems extract heat from a body of water — a lake, river, or groundwater well. They are the most efficient option where applicable (SCOP 4.0–6.0 is achievable), but suitable groundwater conditions are not universally present, and permits from the local water authority (wody.gov.pl) are required before drilling or abstracting water.
| Type | Typical SCOP (Poland) | Install cost range | Ground works |
|---|---|---|---|
| Air-source | 2.8 – 3.6 | 25,000 – 45,000 PLN | None |
| Ground-source (horizontal) | 3.5 – 4.5 | 35,000 – 60,000 PLN | Trenching (300–500 m²) |
| Ground-source (borehole) | 3.8 – 5.0 | 50,000 – 90,000 PLN | Drilling 60–150 m |
| Water-source | 4.0 – 6.0 | 45,000 – 80,000 PLN | Well + water permit |
Insulation requirements
Heat pumps deliver heat at lower flow temperatures than traditional boilers. A gas boiler might heat water to 70–80°C; an ASHP optimally operates with flow temperatures of 35–45°C. This lower temperature works well with underfloor heating (which distributes heat over a large surface area) but requires careful assessment when connecting to radiator-based systems.
For a heat pump to be efficient, the building must be reasonably well insulated. A detached house with poor wall and roof insulation will have a high heat demand that forces the pump to run frequently and at higher temperatures, reducing the seasonal efficiency. Polish building standards have tightened progressively since 2014 (WT 2014 and WT 2021 regulations), meaning newer homes are generally better suited to heat pump retrofits than those built before 2000.
A rough industry guideline: a detached house with a heat demand above 120–150 W/m² (before insulation upgrades) may benefit from thermal improvements before or alongside a heat pump installation.
A building energy audit (audyt energetyczny) can determine the actual heat demand and the minimum insulation level required for a heat pump to operate efficiently. Audits cost 800–2,000 PLN and are sometimes subsidised under Czyste Powietrze.
Czyste Powietrze grants
The Czyste Powietrze (Clean Air) programme is the main subsidy channel for heat pump installations in private homes. It covers replacement of coal, wood, oil, and gas boilers with heat sources that meet the programme's emission and efficiency standards. Heat pumps of all three types qualify.
Grant amounts depend on household income level (three benefit tiers) and the scope of the upgrade. For heat pump installation combined with other works (insulation, windows, ventilation), total grants can reach 90,000–135,000 PLN for the lowest income tier, with progressively lower amounts for higher income households.
Applications are submitted online at czystepowietrze.gov.pl or at the local district fund office (WFOŚiGW). The installer must be certified, and the heat pump must appear on the eligible equipment list.
Combining heat pumps with solar PV
Heat pumps consume electricity, and a PV system generates electricity. Running the heat pump during daylight hours — when the PV system is producing — reduces reliance on grid electricity and lowers the effective operating cost. Some modern heat pump controllers support time-of-use scheduling and can be set to prioritise operation during periods of high solar generation.
As noted in the solar panels article, Mój Prąd 5.0 offered additional grants for combining PV with a heat pump. The two programmes — Mój Prąd and Czyste Powietrze — can in principle both be applied for, covering different equipment in the same installation project.
Maintenance and lifespan
Heat pumps have fewer moving parts than combustion boilers and do not require annual flue cleaning or combustion analysis. Recommended maintenance includes annual checks of refrigerant pressure, heat exchanger cleanliness, and filter condition — typically carried out by an F-gas certified technician. Well-maintained units have a design life of 15–25 years. Compressor replacement (the main wear component) typically costs 3,000–8,000 PLN and is most likely after 10–15 years of operation.