Electric Heater vs Air Conditioning in Spain
An electric heater turns 1 kWh of electricity into about 1 kWh of heat. A modern air conditioning unit in heating mode can turn the same 1 kWh of electricity into 3–4 kWh of heat, making it far cheaper to run.
Resistance Heating vs Heat Pump
All plug-in electric heaters (oil-filled radiators, fan heaters, infrared panels, halogen heaters) use "resistance heating". They are technically 100% efficient because all the electricity is converted to heat. However, air conditioning uses a "heat pump" to move existing heat from outdoors to indoors, achieving efficiencies of 300% to 400%.
| Device | Efficiency | Cost per kWh of heat |
|---|---|---|
| Split AC heat pump | 350% - 400% | €0.026 |
| Oil-filled radiator | 100% | €0.098 |
| Fan heater | 100% | €0.098 |
| Infrared panel | 100% | €0.098 |
Why Electric Heaters Still Feel Expensive
If you run a 2,000W (2kW) oil-filled radiator for 5 hours, it uses 10 kWh of electricity. At €0.15/kWh, that's €1.50 per day just for one room. Do that for a month across two rooms, and your bill jumps by €90.
If you ran an AC unit to provide the exact same amount of heat, it would only use about 2.8 kWh of electricity, costing roughly €0.42 per day.
When a Small Electric Heater is Useful
You should only use a standard electric heater if:
- You don't have AC installed.
- You only need heat in a very small space (like a bathroom) for 15-20 minutes.
- You need a completely silent heat source next to a baby's cot.
Heating with electricity? Your tariff matters.
Upload your bill and we’ll compare over 50 tariffs in Spain to see if you’re overpaying. A bad tariff can double your heating cost.
Upload your billRelated heating guides for Spain
Heating costs depend on the system, the property, and the tariff. These guides explain the most common comparisons in more detail.