Heat pump vs gas boiler
Estimate annual space-heating demand from floor area and insulation class, then compare heat-pump electricity cost (by SCOP) against a gas boiler.
Open calculatorHeat loss through a surface (U-value)
Heat loss (kWh) = U-value [W/(m²·K)] × surface area [m²] × indoor–outdoor temperature difference ΔT [K] × hours / 1,000. Useful for estimating how much energy you save by upgrading windows or adding wall insulation.
U-value in W/(m²·K) — a modern triple-glazed window is ~0.8, a modern insulated external wall is ~0.20, and an uninsulated brick wall can exceed 1.2.
m²
Average indoor-to-outdoor temperature difference during the heating season (e.g. 18–20 K).
K
Length of the heating season in hours (roughly 4,500–5,000 hours in Central Europe).
Cost of lost heat
1,980 zł
Thermal energy lost
2,200 kWh
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Models conductive transmission through a single building element; ventilation losses, thermal bridges and solar gains are not included.
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Educational estimate only. Not medical, tax, legal or financial advice.