New house, no gas mains, heating dilemma

marcus_h

Dear Money Experts. We have had an offer accepted on a house that has electric storage heaters. I haven’t ever had these before, so unsure as to how costly they are – they certainly are ugly. We are going to do some remodeling, so a good opportunity to install something different, if it is worth it.

I presumably could get some new slimline Dimplex storage radiators. Again, I feel these will cost a lot to run.

I am also thinking of a ground heat pump, and might try to get a Green Deal – I can’t see why I would not get the Deal, and it doesn’t sound like the Deal would ending up costing me much more – if any – on a monthly basis. However, I would need to install radiators on the house. That starts to make it look pricey.



We also intend to add an extension in a year or so, on which we might put solar thermal heaters on the roof, and a wet UHF (though only in the extension).

So the heat pump will give me hot water, as would the solar panels on the extension (we are not keen on EV panels). Should the heat pump give me most of what I need in the short term, and does it work well with a solar thermal system? Would a thermal store be needed also? Or in fact, should the ground heat pump give me all I need?

Related to this, I think I am right in believing that you can’t get a second Green Deal once one is in place? So if one was issued to cover the heat pump, I would be out of luck with the solar system – is that right?

The house is a 3 bed semi, with a very large garden that faces due south, not overlooked at all.

Thanks for any help!

Cardew

A Ground Source Heating Pump(GSHP) system can cost well in excess of £20,000, plus cost of most of a Central heating system - radiators/UFH/pipes and new Hot water tank and thermal store.

They are talking about paying 7% interest on a 'green deal' So you can work out the finances yourself, but a non starter.

Solar thermal will provide useful amounts of hot water in summer, but very little in winter when you need heating.

The amount of output from solar thermal is greatly exagerated by salesmen but the new RHI might make it a proposition.

Storage heaters certainly have disadvantages, but overall they would be by far the cheapest solution to run(taking into account capital expenditure), especially as you can heat water and run appliances at cheap off-peak rates.

marcus_h

Thanks Cardew. That was a concern - when added together with central heating, the cost of a GSHP becomes very high (the costs I have seen range from about £9k-17k - I was working on the cheap end of that!) The only thing that made it sound manageable was that the Green Deal loans are only meant to end up costing essentially the same as your bills were before the new install. But the loan probably wouldn't cover the costs of radiators etc.

Do you think the solar/UHF on the extension (about 3mx6m) would rpovide enough heat for the extension itself, approximately, in winter? (given suitable construction etc)

southcoastrgi

solar panels are designed to connect to the hot water cylinder, they aren't designed to run ufh

macman

Since your UHF will mainly be used at night, it would be rather tricky to power it from solar PV panels, which only generate in daylight hours. They wouldn't be powerful enough anyway,m even with a maximum 4kWp system.

jackyann

The best people to talk to about ground source heat pumps are the Centre for Alternative Technology. You can also talk to the Energy Saving Trust, but I found they were more cagey.
CAT told us it is not worth, either from a green or financial pov (am simplifying of course) unless the energy quotient is better than 1:4. ie: for every unit of energy you put in, you get 4 back. A couple of years ago, manufacturers were claiming 4.5-5, but EST found the average was 2-3. Of course, technology moves on.
We have 2 solar thermal panels that heat our hot water. In the summer, they supply most of the hot water for 2 of us, with odd blips. Although they still do well on cold days, you do need another source of heat.
I can only calculate the energy supplied by our photovoltaic cells, not exactly how much is used when. We generate an average of 200 kW hours a month.
We do have underfloor heating and I love it. It is best in a well-insulated home, kept at a low, constant temperature. We keep it on permanently, with thermostats set at 17 in living areas,

marcus_h

macman wrote: »

Since your UHF will mainly be used at night, it would be rather tricky to power it from solar PV panels, which only generate in daylight hours. They wouldn't be powerful enough anyway,m even with a maximum 4kWp system.

Macman - we were thinking of solar thermal panels, rather than PV ones.

marcus_h

jackyann wrote: »

The best people to talk to about ground source heat pumps are the Centre for Alternative Technology. You can also talk to the Energy Saving Trust, but I found they were more cagey.
CAT told us it is not worth, either from a green or financial pov (am simplifying of course) unless the energy quotient is better than 1:4. ie: for every unit of energy you put in, you get 4 back. A couple of years ago, manufacturers were claiming 4.5-5, but EST found the average was 2-3. Of course, technology moves on.
We have 2 solar thermal panels that heat our hot water. In the summer, they supply most of the hot water for 2 of us, with odd blips. Although they still do well on cold days, you do need another source of heat.
I can only calculate the energy supplied by our photovoltaic cells, not exactly how much is used when. We generate an average of 200 kW hours a month.
We do have underfloor heating and I love it. It is best in a well-insulated home, kept at a low, constant temperature. We keep it on permanently, with thermostats set at 17 in living areas,

Thanks JackyAnn. I will give those folks a ring. Very useful.

So does that whole set up (both solar systems) provide you with most of what you need?

Cardew

When you need heating(i.e. winter) solar thermal provides next to nothing(in terms of heating0 even during the day and nothing, obviously, at night.

The cost of the electricity to run the pump and power the electronics will cost a good proportion of the little savings you make in winter.

So forget solar thermal as any form of contribution to heating. Depending on your lifestyle and number of panels, it can provide most, or even all, of your hot water needs in summer and make a contribution in winter.

So does that whole set up (both solar systems) provide you with most of what you need?

Solar PV doesn't generate when dark!!

Again it can save a proportion of your daytime electricity usage, but the main financial advantage is the subsidy for generation(FIT) and selling back to the grid.

marcus_h

Thanks Cardew. It looks as if my only option is to stick with the storage heaters, using E7 topped up with a few PV panels. Anything else looks too expensive and/or not worthwhile.

[Deleted User]

marcus_h wrote: »

Thanks Cardew. It looks as if my only option is to stick with the storage heaters, using E7 topped up with a few PV panels. Anything else looks too expensive and/or not worthwhile.

Have you thought of log burners?