Electric Radiator vs Heat Pump: Which Is Cheaper to Run?

If your question is “electric radiators or heat pump,” the short answer is: it depends on how many square metres you heat and how many hours a day you use the heating. A heat pump delivers between 3.5 and 5 kWh of heat for every kWh of electricity consumed; an electric radiator delivers 1 kWh per kWh, nothing more. That is why, when you heat your entire home for many hours a day, a heat pump is considerably cheaper to run. But if you only need heat in one or two rooms intermittently, an electric radiator costs between €155 and €280 and requires no installation, whereas an installed split system costs around €800–€2,200: with short periods of use, that extra cost will not pay for itself.

This article does not aim to crown a single winner, but to explain which option is best for your situation.

First: What Each Appliance is (and What It Is Not)

electric radiators

An electric radiator is a wall-mounted electric heater made up of aluminium elements that heats a fluid or an internal mass and distributes heat through radiation and natural convection, with a low surface temperature. It is sold with typical power ratings of 500 to 1,800 W, and for 1,000 W models from common brands in Spain, the list price ranges from €155 to €280.

Its real defining feature is comfort: a stable temperature, complete silence, and heat that continues for a few minutes after switching it off thanks to its thermal inertia. This is not an energy-saving feature, and it is important to understand that from the outset.

Electric Heater, Convector and Storage Heater: The Same Family

This is the point most often misunderstood in commercial comparisons. Electric radiators, oil-filled radiators, ceramic radiators, convectors and storage heaters are all electrical resistance appliances. All the electricity they consume is converted into heat inside the room, with 100% efficiency at the point of use, which in practice is equivalent to a COP of 1 (1 kWh of electricity → 1 kWh of heat).

The consequence is inconvenient but decisive: at the same power rating and operating time, a 1,500 W electric radiator and a 1,500 W convector consume exactly the same amount of electricity. What differs between them is how they distribute that heat and how long the room takes to warm up or cool down, not the cost per kWh of heat delivered.

Heat pump: air-to-air and air-to-water

A heat pump does not generate heat: it moves it from the outdoor air indoors through a refrigeration cycle. That is why its efficiency is greater than 1: it delivers more thermal energy than the electrical energy it consumes.

• Air-to-air heat pump (an air conditioner split system in heating mode): this is the cheapest option to install and, according to comparative studies by the OCU, the cheapest to run in an average home. It also cools in summer.
• Air-to-water heat pump (aerothermal heating): heats water that supplies underfloor heating or low-temperature radiators. It is even more efficient, but requires a much larger investment and usually construction work.

The Rule that Decides Everything: 1 kWh is worth 1 kWh… or 4

The entire “electric radiators or heat pump” dilemma can be summed up in a table. SCOP (seasonal coefficient of performance) is the average amount of heat delivered per unit of electricity over an entire heating season, and it is the figure used to calculate the bill.

To put the figures into perspective: a unit with a heating output of 3.5 kW and an SCOP of 4 consumes around 0.9 kW of electricity; producing the same amount of heat with resistance heating would cost 3.5 kW of electricity. In other words, the same home can be heated using between one-third and one-fifth of the electricity.

Two caveats that product websites often omit:

1. SCOP is measured in a laboratory. An SCOP of 4 can only be maintained if the appliance is correctly sized, installed and maintained. A poor installation can reduce nominal efficiency by 20–30%.
2. Heat pumps count as renewable only if they exceed a threshold. Decision 2013/114/EU requires an SPF above 2.5 for an electric heat pump to count as renewable energy. All the units in the table clearly exceed this threshold in a temperate climate; not all do so in a very cold climate.

How the Calculation Actually Works: A Transparent Example Using a Single Room

Before comparing technologies, it is worth understanding how the calculation works. These are the starting figures, along with the source for each one:

Electric Radiators or Electric Heater

Short answer: when it comes to consumption, they are effectively tied; for comfort, the electric radiators wins.

If we compare electric radiators with a “conventional” electric heater (oil-filled, ceramic, or panel), the result on the electricity bill is the same at equal power and operating time, because both use electrical resistance heating with a COP of 1. The difference comes down to three things:

• Thermal inertia and stability. The electric radiators maintain the temperature with fewer fluctuations. This stability has a real, measurable benefit: it allows you to lower the thermostat while maintaining the same feeling of comfort, and each degree you lower it reduces consumption by around 7% (Selectra).
• Silence and heat distribution. No fan, no draughts, and no drying out the air.
• Price. An inertia-based electric radiator costs more than a basic panel heater but less than a split system.

Conclusion: switching from an electric heater to electric radiators does not save energy. It improves comfort. If your goal was to “spend less,” this change will not achieve it.

However, some electric radiators and electric heaters with energy-saving features can help reduce your bill. For example, models with scheduling, Wi-Fi control, and a thermostat allow you to adapt the heating to your schedule and needs, avoid heating rooms when they are not in use, and maintain a stable temperature without overheating the room. The savings do not come from greater efficiency in converting electricity into heat, but from smarter energy management.

Thermal Inertia Electric Radiators or Convectors

Short answer: choose based on how long you use it, not on consumption.

The convector is unbeatable for short periods: a bathroom in the morning or a home office for two hours. Switch it on, warm the air in minutes, and switch it off. The electric radiators are better for rooms used for many hours, such as a bedroom, living room or home office. Its thermal inertia helps prevent the repeated heating and cooling cycles that cause the temperature to rise and fall.

The rule, therefore, is: convector for minutes, electric radiators for hours. The cost per hour of use, I repeat, is the same.

If you want to learn more about the differences between these two types of electric radiators, read our article: “Ceramic vs aluminium thermal emitter: can a dual-core ceramic and aluminium thermal emitter combine the advantages of both?”

Electric Radiators or Heat Pump: the Comparison that Matters

Short answer: if you heat the entire home for many hours a day, the heat pump wins by a wide margin on running costs and pays for itself within a few years.

OCU figures are the most frequently cited in Spain, and it is worth viewing them in context because the figures vary depending on the year of the study and the climate zone considered. These two editions compare a 90 m² home:

The difference between the two columns is not an error: they refer to different years, different energy prices and different climate assumptions. What remains consistent across all editions is the ranking: the heat pump is always the cheapest to run, while electrical resistance appliances are the most expensive.

OCU summarises it as follows: heating an average 90 m² apartment with an air-conditioning heat pump adds around €241 to the annual electricity bill, compared with €1,174 for electric heaters, and its cost-to-performance ratio reaches 350%. However, OCU itself adds two warnings: performance decreases in very cold climates, and the thermal comfort of warm air “is not as good as that offered by other systems.”

When the Heat Pump DOES NOT Win

It would be dishonest to present it as a universal solution. It loses or ties in these cases:

• Occasional use. In the example above, the savings for a single room are around €58 per season. If the installed split system costs between €800 and €2,200, it would take between 14 and 38 years to pay for itself through savings from that room alone. It is not worthwhile.
• Harsh continental climate. At very low temperatures, the SCOP falls, and the unit may need electric backup heating, which returns to a COP of 1. A temperate or warm climate—such as much of the Mediterranean region—is the favourable scenario.
• Poorly insulated home. A high SCOP requires limited heat demand and low flow temperatures. Without insulation, an oversized unit loses efficiency.
• You need quiet comfort without moving air. If noise or draughts bother you, an electric radiator is a better companion.

And When It Clearly Wins

When the heat pump heats the entire home throughout the winter. According to OCU figures, the difference compared with electric heaters is €800–€870 per year. With an installed multisplit system costing around €2,500–€5,500, the investment pays for itself in 3 to 7 years, after which the savings become a net benefit each season. The same appliance also cools the home in summer, which in warm regions avoids the need to buy a second unit.

Electric Radiators or Storage Heater

Short answer: a storage heater only wins with a genuinely cheap off-peak tariff and predictable daily use. In any other case, it is one of the most expensive systems.

A storage heater stores heat in ceramic blocks overnight, taking advantage of off-peak electricity, and releases it during the day. On paper, buying cheap electricity to use hours later is a good idea. In practice, it falls short for four reasons:

1. It depends on the off-peak tariff being genuinely cheap. In 2026, off-peak electricity under time-of-use tariffs costs around €0.10/kWh, compared with peak rates that can exceed €0.16/kWh. If the off-peak rate is not low enough or you end up using the daytime “boost” function, the advantage disappears.
2. You pay for the losses. A 1,500 W storage heater charged for 8 hours consumes 12 kWh a day; three appliances in a home use around 36 kWh a day, costing more than €100 a month at €0.10/kWh, according to. Some of that heat is also lost when nobody is home.
3. Limited control. It adjusts less effectively than an electric radiator with a precise thermostat, resulting in overheating and inconsistent comfort.
4. OCU figures do not vindicate it. In its comparisons, electric storage heaters are the second most expensive technology (€1,046–€1,067/year), behind only electric heaters.

When it makes sense: a home without natural gas, with a time-of-use tariff in place, consistent daytime occupancy and a unit that charges exclusively during off-peak hours. If any of these conditions are missing, a electric radiators with scheduling—which can also operate during off-peak hours—is more flexible and cheaper to buy.

What to Choose for Your Situation

Purchase Cost Versus Running Cost: the Trap of Quick Comparisons

Almost all articles in this category compare only one of these two variables. Both matter:

This leads to the practical rule:

• Single room and intermittent use → the purchase price difference (€600–€1,900) will never be recovered through savings of around €58/year. Choose electric radiators.
• Entire home and intensive use → annual savings of €800–€870 pay for a multisplit system in 3–7 years. Choose a heat pump.

There is a third option that often works better than either: insulate before buying. Reducing heat demand is the only measure that lowers the bill with any system.

How to Effectively Reduce Your Electricity Bill with Both Technologies

1. Schedule heating around off-peak periods. With a time-of-use tariff, off-peak electricity costs around €0.10/kWh compared with more than €0.16/kWh at peak times. Heating during off-peak hours and maintaining the temperature during peak periods reduces the bill without changing the appliance.
2. Lower the thermostat by one degree. Energy-efficiency organisations recommend 19°C in daytime living spaces and 16–17°C in bedrooms; each degree lower saves around 7%.
3. Choose the right size. The reference figure is around 100 W/m² with normal insulation; reduce it to 80–90 W/m² if the home is well insulated and increase it to 120–125 W/m² if it is older or has high ceilings. An undersized appliance runs at maximum power without reaching the desired temperature and consumes more.
4. Check your contracted electrical capacity. Reducing the contracted capacity from 6.9 to 4.6 kW under the PVPC tariff can save between €90 and €140 a year if you have never needed that peak capacity.
5. Do not heat rooms you are not using. An electric radiator's consumption depends on its actual operating time, not just the wattage on the label: a 1,500 W appliance with a thermostat that heats for only one-third of the time consumes around 0.5 kWh per hour, and that is what you are billed for.

If you want to discover more tips for saving energy with heating, read our article: “Low-consumption electric radiators: do you save or spend more?”

Frequently asked questions

Conclusion: choose based on your situation, not a slogan

There is no single winner between electric radiators and a heat pump, and anyone who tells you otherwise is trying to sell you something.

If you heat one or two rooms for only a few hours and use the heating irregularly, an electric radiator is the sensible choice: €155 to €280, no installation, silent operation, and a stable temperature. Your bill per kWh of heat will be higher, but with this pattern of use, the savings from a heat pump would never recover the difference in purchase price.

If you heat the entire home throughout the winter, the heat pump is the clear winner. It delivers the same heat using one-third to one-fifth of the electricity, and OCU studies consistently rank it as the cheapest option to run year after year: €306–€455/year compared with €1,174–€1,255/year for electric heaters in a 90 m² home. It pays for itself in 3–7 years and also provides cooling in summer.

In both cases, the most cost-effective decision is not to choose an appliance, but to reduce heat demand: insulation, scheduling and a properly adjusted thermostat lower the bill with any technology. Start there.