Costs of Running an Immersion Heater

carytb

I have an immersion heater heating a well lagged cylinder which is used to supply a power shower which is used mainly in the morning and occasionally in the early evening. My question is is it more cost effective to keep it permenantly on or use a timer to switch it on and off in anticipation of when I will want to use it.

Cardew

Welcome to the forum.

If you do a search you will find a lot of threads on this.

It is without dispute *more cost effective to have it on a timer. The analogy is would you keep a kettle boiling all day?

From the Energy Saving Trust

Question
Won't turning my hot water heater on and off cost me more in the long run?


Answer
No. Water heaters use more energy to heat water and maintain a high temperature for an extended period, than they do to heat it up the once.

That said with a well lagged tank you may find surprisingly little difference between both methods.

* No doubt it will be disputed by those who have 'proved' otherwise; and thus defied every law of physics.