Best way to heat water with electric

amtrakuk

I've got a 12KW redring powerstream to provide hot water for the house.

From what I can gather, a storage heater system seems to be the standard way of heating water, I decided not to go down that route as Id have thought it works out expensive as it keeps heating the water when your not using it.

The con with the powerstream is the flow rate is low and I believe 12KW is the maximum a single phase supply can utilise

Is there a better way with a higher flow rate without going 3 phase! lol

I heard there are things called heat stores, I dont know much about them, are they any good? do they work out expensive to run?

Thanks

tomstickland

If you have economy 7 then it is cheaper to heat the water overnight.
I've done the sums on it.

Heat loss from the tank is about 3 units per day.

I mainly use the hot water for washing up and estimate 3 bowls per day. A bowl requires about 0.3 of a unit, so I'm only using 1 unit of energy per day.

So it's either 1 x 16p (daytime)
or (3+1)*4p (Econ 7).
It's already breaking even on that low usage, so if you use more hot water it will be cheaper to heat overnight.

Of course, the heat loss from the tank heats the house too.

I've read up on heat stores. The main problem is that the water isn't stratified like in a tank. In a normal tank the hot water comes off the top and cold is taken in at the bottom. This means that you receive hot water until it runs out. With a heat store the temperature of the water will drop off with time. I've no experience of that and I couldn't get a straight answer on the screwfix forums.

amtrakuk

hi Tom,

I don't have E7 unfortunately Just standard rate. I did look at getting E7 in the house but was going to be costly to buy storage heaters and I heard many horror stories about the heat retention of storage heaters running out mid afternoon/early evening thats why I went for regular 30.00 convection heaters and a powerstream. I dont have a problem with the house heating I just am getting warey of waiting half an hour to fill a bath, would be nice to have a higher flow rate.

i have been looking at cistern type heaters but space is a bit limited. I looked at Unvented systems but looked a nightmare with annual servicing and the cost and legalities of installing one

amtrakuk

http://www.heatweb.com/products/cylinders/heatbank/heatbank.htm

Looks good has anyone had any experience?