Infrared heater efficiency is often misunderstood. Conversion efficiency is close to 100% because an infrared heater converts virtually all the electricity it uses into heat. Whether it heats economically depends on the building, the controls and how you use the room.
This guide explains the difference between conversion efficiency and energy efficiency, compares infrared heaters with convector heaters, fan heaters and heat pumps, and shows you how to calculate electricity consumption yourself.
Infrared heater efficiency in figures
Efficiency describes how much of the energy supplied becomes useful energy. For a direct electric heater, the calculation is straightforward: 1 kWh of electricity generally produces 1 kWh of heat. There is no flue, no exhaust and no heat lost through pipework, because the heat is produced in the room itself.
That figure is not specific to infrared heating. A convector heater or fan heater also turns 1 kWh of electricity into 1 kWh of heat. Efficiency alone does not explain why warmth from an infrared heater feels different. The difference lies in how the heat reaches you.
Radiant heat rather than warm air
An infrared heater releases a large proportion of its heat as radiation. It warms walls, floors, furniture and people, which in turn release heat into the room. A convector heater primarily warms the air, which rises and collects near the ceiling. The proportion delivered as radiant heat depends on the heater’s design, surface temperature and installation.
Many people find radiant heat comfortable at a slightly lower air temperature. In its overview of infrared heating, the German motoring association ADAC cites a difference of two to three degrees. Whether that applies in your home depends on how you use the heating. Do not assume this potential saving when planning.
Heat conversion efficiency is not the same as energy efficiency
Heat conversion efficiency describes the heater itself. To assess infrared heater efficiency in practice, you need to look at the result: how much electricity does it take to keep your room warm over a heating season? Insulation, room size, your preferred temperature, hours of use and temperature controls all affect that figure.
The same heater can therefore use relatively little electricity in a well-insulated study but much more in a draughty hallway in an older building. Its heat conversion efficiency is the same in both places. To understand how efficiently an infrared heater will work in your home, you need to consider the room, not just the heater’s rating plate.
What does the figure on the product information sheet mean?
Electric local space heaters are subject to EU ecodesign requirements, governed since 1 July 2025 by Regulation (EU) 2024/1103. The product information sheet therefore gives a seasonal space heating energy efficiency figure. This is not heat conversion efficiency in the physical sense. It takes account of factors including the energy used to generate electricity and the type of temperature control. For direct electric heaters, the figure is therefore well below 100%. A low figure does not mean heat is being lost at the heater.
Infrared heater efficiency compared with other heating systems
Comparing infrared heaters with other electric heating systems helps put their energy efficiency into context.
| Heating system | Heat from 1 kWh of electricity | Typical use |
|---|---|---|
| Infrared heater | About 1 kWh of heat, much of it as radiant heat | Individual rooms, supplementary heating, well-insulated buildings |
| Convector heater, fan heater | About 1 kWh of heat, mainly as warm air | Short periods of heating |
| Heat pump | Around 3 kWh of heat, depending on the building and system | Central heating for the whole home |
A heat pump also draws on heat from its surroundings, so it delivers around three times as much heat from the same amount of electricity. It uses less electricity in operation than any direct electric heater to provide the same amount of heat. Purchase, installation and maintenance are considerably more involved, however.
An infrared heater needs neither a plant room nor pipework. It is mounted on a wall or ceiling and connected to the electricity supply. It is particularly suited to spaces with low heat demand or rooms that are heated only occasionally.
Efficiency alone is not a useful basis for comparison with gas heating, because gas and electricity have different costs per kilowatt-hour. Instead, compare annual costs, including purchase and maintenance.
When is an infrared heater efficient?
Infrared heater efficiency depends largely on where and how the heater is used. The less heat a room needs and the shorter the time it is occupied, the better suited a direct electric heater may be. Four typical situations are:
- Well-insulated buildings: New builds, passive houses or renovated older properties with low heating demand.
- Rooms used for short periods: Bathrooms, guest bedrooms, hobby rooms or home offices.
- Supplementary heating: During spring and autumn, or in a single room while the central heating remains off.
- Rooms without radiators: Extensions, converted lofts or conservatories, provided the heater is approved for use in that space.
An infrared heater is less suitable as the sole source of heat in a poorly insulated house. Electricity consumption adds up over winter, and a central heating system costs less to run in that situation.
Four factors that determine energy use
In everyday use, infrared heater efficiency depends on four factors. You can influence each of them.
- Insulation: This has the greatest effect. Your heater must replace the heat lost through walls, windows and the roof.
- Room size and heater power: An undersized heater may run continuously without reaching your chosen temperature. A starting point is about 100 W per square metre in an insulated room with a ceiling height of 2.4 m. Older buildings, large areas of glazing and higher ceilings may require more power.
- Control: A thermostat switches the heater off once the set temperature is reached. A weekly programme lets you heat the room only when it is in use. Our guide to thermostats for infrared heaters explains the available options.
- Ventilation and placement: Opening windows fully for a short time loses less heat than leaving a window ajar. Position the heater so it can radiate freely into the area you use, directing warmth where you need it. See our guide to spacing and placement for details.
Calculate your electricity use
Multiply the heater’s power in kilowatts by its operating time in hours to calculate consumption in kilowatt-hours. Because the thermostat switches the heater on and off, use the time it is actually heating. This is less than the time you spend in the room.
| Power | Operating time per day | Consumption per day | Cost at 38 cents per kWh |
|---|---|---|---|
| 300 W | 4 hours | 1.2 kWh | €0.46 |
| 600 W | 4 hours | 2.4 kWh | €0.91 |
| 900 W | 4 hours | 3.6 kWh | €1.37 |
The electricity price of 38 cents per kilowatt-hour and the four-hour operating time are figures for this example. Use your own tariff and check how long your heater actually runs on a cold day. For a fuller explanation and more examples, see our guide to infrared heater electricity use.
Infrared heaters and solar power
Electricity from your own solar panels reduces the cost of running an infrared heater. However, a photovoltaic system produces the least electricity in winter, when heating demand is highest. Do not plan to run the heater mainly on your own solar power.
The two work well together in spring and autumn. On sunny days, your solar panels can supply some of the electricity used for heating, allowing your central heating to stay off for longer.
What about CO2 emissions?
Emissions also matter when assessing infrared heater efficiency. The heater itself produces no exhaust gases. Emissions arise from electricity generation and depend on your electricity tariff and the generation mix. It would therefore be misleading to make a general claim about CO2 savings compared with other heating systems.
If you want to reduce the climate impact of your heating, there are two factors you can influence: lowering heat demand through insulation and heating controls, and using electricity from renewable sources.
Opranic P5, P6 Hybrid and P7 at a glance
All three models are direct electric heaters with the conversion efficiency described above. They differ in finish, power and controls.
| Model | Controls | Suitable if |
|---|---|---|
| Opranic P5 Metall | External room thermostat required | You want a simple heater for wall or ceiling mounting. |
| Opranic P6 Hybrid | Built-in thermostat with rotary control | You want to plug it in and start heating straight away. |
| Opranic P7 Glas | External room thermostat required | The heater will be visible in your living space and you want it to blend in. |
In everyday use, how you control an infrared heater matters more to energy efficiency than which model you choose. Pair the P5 and P7 with a thermostat that has a weekly programme and open-window detection.
Frequently asked questions about infrared heater energy efficiency
How much of the electricity used by an infrared heater becomes heat?
Nearly 100%. As a rule, one kilowatt-hour of electricity produces one kilowatt-hour of heat. The same applies to all direct electric heaters.
Is an infrared heater more efficient than a fan heater?
Both convert electricity to heat at the same rate. The difference is how they deliver it: an infrared heater warms surfaces and people directly and operates silently, while a fan heater blows warm air into the room.
Does an infrared heater use a lot of electricity?
That depends on its power, how long it runs and the building. A 600 W heater uses 2.4 kWh over four hours. In a well-insulated room with a thermostat, it needs to run for less time.
Infrared heater or heat pump: which is more efficient?
In terms of electricity consumption, the heat pump: it delivers around 3 kWh of heat from 1 kWh of electricity. An infrared heater is simpler to buy and install and is suited to individual rooms and low heating demand.
Can an infrared heater serve as the main source of heating?
It can in a well-insulated building with low heating demand. In a poorly insulated house, it is better suited to providing additional heat in individual rooms.
How can I improve my infrared heater’s energy efficiency?
Choose the right power for the room, use a thermostat with a weekly programme, position the heater so it can radiate heat without obstruction, and ventilate briefly and thoroughly.
Find the right infrared heater for your room
Tell us your room size, insulation standard and how you use the space. Opranic can recommend the power output, model and controls that suit your room.
Sources: ADAC, the German motoring association (heater efficiency and comparison with heat pumps); Opranic catalogue (guide to heating power); Regulation (EU) 2024/1103. Worked examples use assumed values. Checked in October 2026.
