EV Night Tariff for Immersion Heater

Andycrfs

I’m about to switch to an ev tariff for cheaper (about <25% of day rate). Would it be worth me making sure that my immersion is full by the end of the night time tariff? I’ll probably trail it to see, but grateful for any pointers.

lohr500

How are you heating your immersion tank now?

If you are using electricity, then definitely fit a timer to the immersion heater (the lower of the two if it has a twin immersion heater set up) to take advantage of the off-peak EV rate.

What rate will your EV off peak electricity be? It may still be cheaper to heat the hot water with gas if you are going so already.

Just check your off peak times as many off peak times don't change with the +/- 1 hour GMT/BST time shift. Any timer you fit will need to be kept in sync with the off peak rate. My timer has an option to auto adjust for GMT/BST or not. I have it set to stay on GMT and always make sure the clock is set on GMT. Worth checking the clock periodically as well to make sure it hasn't drifted, otherwise it could switch on the immersion heater during the https://policy.friendsoftheearth.uk/insight/future-drax-old-inefficient-damaging-and-expensive peak rate electricity period.

If your tank isn't well insulated, add some more insulation as this will help to keep the water hot during the day and into the evening.

DeeQS

I do this. I run the immersion heater for two hours on a timer during my EV rate (7.5p). It uses about 2 or 3 kWh (depending on previous days hot water usage) to heat. It’s enough to last the day with up to 4 showers.

dunstonh

And its not uncommon for meters to go out of sync with the regional time.  Sometimes only minutes over the years but sometimes hours.