Putting to rest an urban myth about leaving the heating on

We are often told that people have "heard" that it is more energy efficient to leave your heating on, than to turn it off during the day when you are out and at night when you are in bed. The argument is that the energy taken to warm up the room from cold is greater than that needed to keep the room warm by leaving the heating on all the time. This has never sounded particularly believable to us so it is a relief to find that the Royal Academy of Engineering has finally put this myth to death.

The RAEng has published a very interesting paper on "Options for heating homes in a low carbon economy". It's much more interesting than it sounds! On page 17, they do a study on a 1980's house measuring the energy taken to heat a living room. They measure the energy required to heat it twice a day, and then to keep it heated.  This is the key paragraph:


An experiment on this room showed that, by keeping the heating on all day, the peak power demand could be reduced from 4.2 to 1.6kW but the overall energy consumption went up from 13 to 38kWh/day.

So never again should anyone subscribe to this urban myth. It doesn't pay to keep your heating on. Incidentally, if you want a device to allow you to manage the heating of individual rooms check out our programmable radiator valves.