SpeedComfort radiator fans Duo: under 0,32 euro of electricity a year

A living room in November: the thermostat sits at 20 and the window end is still cold, because the radiator sends warm air up the wall to the ceiling while the sofa gets very little of it. Dutch consumer confidence in August is −34 against a twenty-year average of −12, and housing costs are up 4,3% year on year. In a year like that, moving the heat you already paid for is more practical than replacing equipment.

SpeedComfort makes a strip of magnetic fans that clips under the bottom edge of a radiator. The Duo set is two strips of three fans each, with a 12 volt adapter and a magnetic temperature sensor switch that starts them when the radiator warms up and stops them when it cools. Two numbers on the listing are worth writing down on their own: under 20 dB(A) of noise and under 0,32 euro of electricity a year. The maker also claims that, combined with a thermostat set 1 to 2 degrees lower and a boiler flow temperature of 60 degrees, you can save up to 22% on gas.

Renters are drawn to this kind of product because it touches neither the walls nor the boiler and peels off to come with you. Two things need measuring first. One is the distance from the radiator to the socket, since the supplied cable is only 1,8 metres. The other is radiator length: the specification table says it fits 75 to 120 centimetres while the description on the same page says 70 to 120, and those five centimetres decide whether yours qualifies, so it is worth asking before ordering. A radiator boxed into a cabinet or hidden behind a long curtain will not push air out anyway.

• A Duo set covers one radiator. Count the radiators you actually run, multiply the set price by that number, and that is the real cost of being able to turn the thermostat down
• An independent benchmark: Milieu Centraal puts one degree lower on the thermostat at roughly 170 euro a year, assuming 1,37 per cubic metre of gas, a moderately insulated 1970s house and two occupants (checked 2026-08-27)
• The maker's "up to 22%" is the combined result of the fans plus a lower thermostat and boiler temperature, not what the fans produce on their own; read it as a ceiling rather than an expectation

Lay the sum out like this. Divide 170 by 1,37 to get roughly 124 cubic metres of gas per degree, multiply that by the gas price on your own bill, and you have what one degree is worth to your household in a year. Multiply by the number of degrees you are genuinely willing to give up, then divide by the set price times the number of radiators, and you have the payback in years. The electricity term you can simply drop: under 0,32 euro a year does not reach the first decimal place.

Price

€103 - Duo set of two strips

Rating

4,3 / 511

Specs

3 fans per strip - 1,8 m cable - 10-year maker warranty

Platform

bol marketplace seller DCK Magazijn

Checked

2026-08-27