Immersion heaters and economy 7

Grando101

Hi, I'm thinking about getting an immersion heater fitted so that I do not have to use my gas back boiler in the summer to heat the water. If I were to do this (disconting the cost of installing the immersion) do you think I would save anything on my fuel bills by heating the water for half the year on Economy 7 at night. Other night-time appliances would be the dishwasher.
However, I work at home so am here during the day, which leads me to think Economy 7 may actually end up being dearer.
And on related note, although sites like Uswitch give estimates, they don't appear to ask anything about the nature of your usage - is there a way of finding out if there is a cheaper utility company for people like me who are in during the day (i.e maybe paying a standing charge, but lower per unit rates?)
Cheers,
Ed

Cardew

It is difficult but not impossible to make E7 pay if you don't have storage heating.

The 'break even point' for it to become financially viable varies according to the company you use, the area of the country in which you live and your total consumption of electricity. It is just over 30% usage on E7 for myself - BG in Midlands; but can vary between 15-40% on E7.

Another factor is how efficient your gas back boiler is to heat water only - I have read that some models are pretty poor. It would be fairly easy to check by using gas for a few days and electricity for the same amount of time.

In some properties there is a noise problem with dishwasher/Washing Machine coming on in the early hours.

When on E7 I found we were putting on the dishwasher at night when not full to take advantageof E7 rates - a false economy.

I couldn't make E7 pay so changed to normal.

dc

My thoughts, apart from improving efficiency at a cost, by ditching the back boiler and fitting a condensing boiler or mabe a condensing combi. You are probably better off staying as you are on cost.

Gas is roughly up to a quarter the cost of non E7 electricity per Kilowatt. Thus if your back boiler is only 50% efficient, then it will still be half the price of heating the water by a "100% efficient" immersion heater. As you work from home I think the daytime useage could be prohibitive.

Analyse your daily useage, and then compare any possible daily savings with your current gas and electricity bils over the year, based on Kws used.

HTHs dc