How Much Electricity Does a Ventilation System Use?
A ventilation system runs around the clock, and that is exactly what makes many homeowners hesitate: won't that drive up the electricity bill? If you want a realistic estimate of the power consumption of a ventilation system, you should not rely on gut feeling but look at the actual watt and kilowatt-hour figures. Modern units are more economical than most people think.
In this guide, we show you how much electricity controlled residential ventilation really draws, what the running costs per year amount to and why the system often saves more than it consumes in the end. You will also learn which simple measures keep consumption low over the long term.
How much electricity does a ventilation system really use?
Consumption depends heavily on the system type and size. A central ventilation system with heat recovery for a single-family home needs on average about 400 to 550 kilowatt-hours per year. Smaller systems, for example for an apartment of around 150 square meters, often manage with 100 to 200 kilowatt-hours a year.
Decentralized ventilation units, which work room by room, consume only between 5 and 50 watts per unit, depending on the fan speed. If such a unit mainly runs at a low setting, annual consumption remains correspondingly low. You can read about the basic differences between central and decentralized systems in our comparison of central and decentralized ventilation.
What determines power consumption
The most important parameter is the so-called SFP value (Specific Fan Power). It describes how much electricity the fans need to move a certain volume of air. The lower this value, the more efficiently the system works. Modern units with energy-saving EC motors achieve significantly better values here than older models with conventional AC motors.
The condition of the filters is just as crucial. If they are dirty, the fans have to work against higher resistance and draw more power. An oversized system or a permanently high airflow rate also drives up consumption. Demand-controlled operation, for example via humidity or CO2 sensors, on the other hand keeps power demand low. Our article on filter classes for ventilation systems explains which filters are due when.
Electricity costs per year: a sample calculation
At an electricity price of around 37 cents per kilowatt hour, the running costs are easy to estimate. The following table shows typical orders of magnitude:
| System type | Consumption per year | Electricity costs per year |
|---|---|---|
| Decentralized (single unit) | approx. 40 to 150 kWh | approx. €15 to €55 |
| Central MVHR, apartment approx. 150 m² | approx. 100 to 200 kWh | approx. €37 to €74 |
| Central MVHR, single-family home | approx. 400 to 550 kWh | approx. €148 to €204 |
These values are guidelines. Actual consumption depends on the running time, the selected fan speed and the efficiency of the unit. If you ventilate a lot at a high setting, you will be at the upper end; with demand-controlled operation, you will be well below it.
Electricity in, heating costs out: the overall balance
What matters is the overall picture, not the fan power alone. A ventilation system with heat recovery recovers up to 90 percent of the heat from the extract air and transfers it to the fresh supply air. As a result, significantly less heating is required. According to the German Environment Agency (Umweltbundesamt), ventilation heat losses of only 4 to 8 kilowatt-hours per square meter per year compare with just 1.5 to 2.5 kilowatt-hours of fan electricity.
All things considered, a well-planned system therefore usually saves more heating energy than it consumes in electricity. Electricity use is therefore not a pure cost item, but an investment in a healthier indoor climate and lower heating costs. Our guide to heat recovery shows how it works technically. You can find suitable units in our Ventilation Systems category.
How to reduce power consumption
A few simple measures will keep consumption low over the long term. Replace the filters regularly, because clean filters reduce resistance and thus noticeably lower the power requirement. Use demand-controlled operation and ventilate only as much as necessary instead of letting the system run permanently at a high setting. When buying a new unit, look for EC motors and a good SFP value.
Maintenance also pays off: dirty heat exchangers and ducts reduce efficiency. A fixed maintenance schedule keeps the system economical and durable. Our maintenance plan for the ventilation system provides a structured overview. You can find replacement filters and accessories at any time in our Air Filters category.
Putting power consumption into perspective in everyday life
To make the figures tangible, it helps to compare them with other household appliances. Depending on the model, a modern refrigerator consumes around 100 to 300 kilowatt-hours per year, and a clothes dryer in frequent use quickly reaches several hundred. An efficient ventilation system is therefore in the same range as a refrigerator, but it runs continuously and constantly provides fresh, filtered air.
It is also interesting to look at a single day: spreading 400 kilowatt-hours a year over 365 days gives just over one kilowatt hour per day, or around 37 cents. That roughly corresponds to the cost of a single hour of vacuuming or briefly using the oven. Against this background, the high consumption many people fear is put firmly into perspective, especially since, unlike these appliances, the system actively saves heating costs and improves air quality.
Frequently asked questions
Does a ventilation system really run continuously?
Yes, controlled residential ventilation is designed for continuous operation, usually at a low base setting. It is precisely this steady, economical operation that ensures a consistently good indoor climate with low power consumption.
Does a decentralized system use less electricity than a central one?
Per unit, yes: decentralized units often draw only 5 to 50 watts. In total, however, it depends on the number of units. For individual rooms they are very economical, but for an entire house, an efficient central system can come out cheaper in the overall balance.
Will a ventilation system noticeably increase my electricity bill?
Usually not dramatically. At €15 to around €200 per year, the cost is manageable, and the heating costs saved through heat recovery often more than offset it.
How can I recognize an energy-saving unit?
Look for EC motors, a low SFP value and a good energy efficiency class. You can find this information in the manufacturers' technical data sheets.
Conclusion
The power consumption of a ventilation system is lower than many fear: depending on type and size, it ranges from about €15 to €200 per year. The decisive factors are the SFP value, efficient EC motors, clean filters and demand-controlled operation. More important than consumption alone is the overall balance, because thanks to heat recovery, the system usually saves more heating energy than it costs in electricity. If you pay attention to efficiency and regular maintenance, you can run your ventilation system economically over the long term. You can find suitable ventilation systems, replacement filters and accessories in our shop under Ventilation.
