Calculate heating costs and compare energy sources
Gas, heating oil, heat pump, district heating or pellets – making costs transparent
The formula for heating costs is simple: annual cost = annual consumption × price per unit. 15,000 kWh of gas at €0.12/kWh results in €1,800 per year – or €150 per month. The harder part is knowing your own consumption and the right price. Consumption is shown on your meter or your supplier’s latest annual statement, and the price is in your current tariff.
CO₂ levy since 2021: Fossil fuels such as natural gas and heating oil have been subject to a national CO₂ levy since 2021. In 2025 it amounts to €55 per tonne of CO₂. For natural gas that adds around 1.0 cent/kWh, for heating oil around 1.5 cents per litre. This levy is already included in most current supplier prices – check your tariff contract. The levy is set to keep rising until 2026, further increasing the incentive to switch to heat pumps and renovate buildings.
Energy consumption and building standard: A building’s energy demand depends heavily on its insulation quality. An unrenovated older building can consume 200–300 kWh/m² per year, while a KfW Efficiency House 55 needs only 55 kWh/m². For 150 m² of living space, that is the difference between 30,000–45,000 kWh and 8,250 kWh. Insulation measures (roof, façade, basement) typically reduce consumption by 20–40% – with correspondingly lower heating costs.
Don’t forget additional costs: Our calculator shows the pure consumption costs. On top of that come the supplier’s base fee (€50–200/year), heating system maintenance (gas: €150–300/year, oil: €200–400/year), chimney sweep fees (€50–150/year) and any reserves for replacing the heating system. Total costs are therefore typically 15–25% higher than the pure energy costs.