Heating cost calculator — compare heating sources

Annual cost = annual heat demand (kWh) × unit heat price (PLN/kWh). Example: 15,000 kWh at PLN 0.40/kWh (gas) = PLN 6,000/year.

Old uninsulated house (200 m²): 20,000–30,000 kWh/year. House meeting 2021 building regulations (150 m²): 12,000–18,000 kWh/year. Passive or near-zero energy house (150 m²): 4,000–9,000 kWh/year.

At 2024–2025 prices: coal (~PLN 0.25/kWh heat), heat pump COP 3.5 (~PLN 0.24/kWh), pellets (~PLN 0.35/kWh), gas (~PLN 0.40/kWh). Direct electric heating is most expensive at ~PLN 0.85/kWh.

COP (Coefficient of Performance) is the ratio of heat output to electrical input. At COP = 3.5 the effective heat cost = PLN 0.85 ÷ 3.5 ≈ PLN 0.24/kWh — cheaper than gas. A higher COP means lower running costs.

Effective measures: insulate exterior walls and roof (save 20–40%), replace windows with energy-efficient ones (5–15%), install mechanical ventilation with heat recovery (15–25%), lower thermostat by 1°C (saves ~5–6%), use a programmable thermostat, seal draughts.

Natural gas (grid): ~PLN 0.35–0.45/kWh heat. Heating oil: ~PLN 0.45–0.55/kWh (varies with crude oil price). For a 15,000 kWh/year house the difference is about PLN 1,500–2,000/year in favour of gas. Where no gas grid is available, LPG is an alternative but is 20–30% more expensive than natural gas.

Pellets are one of the more cost-effective heating sources in Poland. Heat cost: ~PLN 0.30–0.40/kWh. A pellet boiler costs PLN 8,000–20,000 and annual running costs for 15,000 kWh are about PLN 4,500–6,000. Additional benefits: low emissions (Class 5 boilers), Czyste Powietrze subsidy eligibility.

Calculate the cost per kWh of heat for each fuel: gas (calorific value ~10 kWh/m³): price per m³ ÷ 10; coal (~7–8 kWh/kg): price per kg ÷ 7.5; dry wood (~4 kWh/kg): price per kg ÷ 4; pellets (~4.9 kWh/kg): price per kg ÷ 4.9. Then multiply by annual demand and divide by boiler efficiency (85–95%).

Main programmes: Czyste Powietrze — up to PLN 136,500 for replacing a "kopciuch" boiler and thermal renovation (up to 90% of costs for low-income households); Moje Cieplo — grant up to PLN 21,000 for a heat pump; thermomodernisation tax relief — up to PLN 53,000 deducted from PIT/CIT.

Methods: review past gas or coal bills (1 m³ gas ≈ 10 kWh); check the energy performance certificate (required for sale/rental); use the simplified formula: floor area (m²) × EP indicator (kWh/m²·year). EP: old house 200–350 kWh/m²·year; retrofitted house 80–150 kWh/m²·year; passive house < 15 kWh/m²·year.