Does anyone have an electric boiler?

matelodave

Haveyougotenoughtime said:

Hmmm - so @matelodave - how about an electric boiler for the water and individual heaters?
Are the individual heaters efficient?

Thanks

please dont confuse efficiency with cost. All electric heaters are 100% efficient insofar as they convert 100% of the leccy into heat but they cost 5 times as much as gas to run. Same with heating water.

Gas boilers are about 90% efficent but would have to be down to around 20% efficient to equal the running cost of leccy

As as others have pointed out there was a spate of threads earlier this year from people who'd moved into small flats or houses with Electric Flow Boilers and couldn't understand why their leccy bills were sky high and what they could do about it (it usually happens when the winter bills roll in around the end of March or the begining of April)

The only solution was to stop using it, replace it with gas or even electric storage heaters (which do at least use off peak energy and is generally a fair bit cheaper than peak rate) or use individual room heaters.
Heating a water tank overnight using off-peak leccy is also a lot cheaper than using an electric boiler on peak rates..

It's entirely up to you but you'll also probably find the place a lot harder to sell in the future.

Gas isn't going to go away and unless leccy comes down in price or gas goes up in price to meet somewhere in the middle then gas will remain the fuel of choice for a long while.

Reed_Richards

However the OP has two threads on the go and on the other one it has been established that they do not have access to mains gas.

molerat

In parts of Scotland some councils, with the assistance of Scottish Power, fitted these wet electric systems to their housing stock. They are now ripping them all out and fitting gas CH incurring part of the cost of laying gas mains in the estates.  In my area the council are paying the tenants a subsidy to cover part of the electric bill.

I currently pay 2.6p per kWh of gas and 12.6p  for electric.  Even if my antique boiler is only 60% efficient it will still cost 3 times the amount to put the same amount of heat into my house with electric.  Even an ASHP with 3.5 x efficiency is only marginally cheaper and then I would still have to heat the water on top.

matelodave

Air to Water heatpumps provide both heating and hot water. Air to Air heatpumps (air conditioning) require additional provision for hot water

macman

Your other option is the tried and tested one of using E7 with NSH's and an immersion heater. Not as cheap as main gas CH, but a lot less capital cost than a heat pump.
And, to answer your next question, NSH's are 100% efficient.

Reed_Richards

The trouble with Economy 7 is that the night rate isn't nearly as cheap as it used to be and the day rate can be extortionate.  A quick check for my area cannot find a night rate less than 10p per kWh and the day rate going with it is over 20p per kWh.  It looks to me as if Economy 7 has been quietly phased out to the point where it saves you next to nothing.    

QrizB

Reed_Richards said:

It looks to me as if Economy 7 has been quietly phased out to the point where it saves you next to nothing.    

I find the same in my area. Unless you make a lot of use of the off-peak tariff it's likely to be cheaper to take a low single rate rather than a peak and off-peak one.

One exception could be Octopus Go or Go Faster, where the off-peak period is only 3 to 5 hours but the rate is much lower around 5p while the peak rate of around 15.5p (in my area) is still pretty competitive.

matelodave

QrizB said:

Reed_Richards said:

It looks to me as if Economy 7 has been quietly phased out to the point where it saves you next to nothing.    

I find the same in my area. Unless you make a lot of use of the off-peak tariff it's likely to be cheaper to take a low single rate rather than a peak and off-peak one.

One exception could be Octopus Go or Go Faster, where the off-peak period is only 3 to 5 hours but the rate is much lower around 5p while the peak rate of around 15.5p (in my area) is still pretty competitive.

The only way to make that work is to use bigger, higher capacity storage heaters to ensure that you can store as much heat as you can in 3-5 hours rather than the normal seven that they are designed for. 

eg a 2kw storage heater will store 14kwh in seven hours but only 6-10 in a 3-5 hour window.,  You's need a 2.8 kwh heater to store 14kwh in 5 hours but even a 3.5kw heater would only manage 10.5kwh in 3 hours.

The same with hot water - it takes about 10kwh to heat a 150 litre tank from 10-60 degrees, so you'd just about manage it with a 3kwh immersion heater in three hours.

However,  if you were profligate with hot water or had a bigger tank you'd need more energy which would be costing you peak rate. (ideally a bigger 200-250 litre tank with two immersion heaters so you could heat it all during the off-peak period and have enough to keep you going all day

Not saying it cant be done but it does need the sums to be done to make it work

Be_Happy

I do have an electric boiler.  Flats are fitted with storage heaters and gets its hot water from an electric boiler (not an immersion heater).

Boiler is a McDonald Thermflow combination electric.  It stores overnight and uses 3 kw nightly.  Heating capacity is 140 litres and I get very hot water all day and evening.  I am a low user -1 person, shower, wash hand basin and kitchen sink (no laundry usage).  There are larger sizes available, depending on no of bedrooms - this one is rated suitable for 2 bed house.

This system has been used in flats as boiler cupboards have no outside wall, so no overflow necessary and no separate water feed tank.

coffeehound

Be_Happy said:

I do have an electric boiler.  Flats are fitted with storage heaters and gets its hot water from an electric boiler (not an immersion heater).

Boiler is a McDonald Thermflow combination electric.  It stores overnight and uses 3 kw nightly.  

Although a bit different from a basic hot water cylinder, they are still heated by immersion heater