Anyone know anything about Ground source heat pumps?

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As it says -
I'm on mains gas...have solar pv panels (east west 4kW)

Was thinking about Solar Thermal -but now even with RHI payments thinking I will never get my money back ....

Trying to be eco friendly - and avoid the gas price hikes...

Not bothered about making money more about covering costs and being warm enough ...quote is about £20k

3 bed detached (floor area approx 112m2) is/will be well insulated - cavity walls, 270mm+ loft, celotex under floor and have a wood burner but don't want to depend on that...

Any one have it? Any opinions of it?
 
I don't have it but did briefly work in a commercial building where it was working. The main issue I see is the vast amount of work required to install it and the cost of the equipment needed to run it. I don't know what size your garden is but there would be a lot of digging out to install the pipe runs and then install the actual kit to run it.

I would have thought there would be little, if any, return on investment and it is probably only a viable alternative when building a property from scratch. You will probably be dead before there are any financial benefits but you wouldn't be completely reliant on fossil fuels so long as you can produce enough PV leccy to run the kit.
 
A subject I studied, fair to say at the outset that the economics are still unclear, although where they have been installed successfully the results are subject to a holistic upgrade (where required) of the property in general, insulation, air tightness, heat exchange ventilation, to scoop the whole benefit(s)
Are there still government grants available for this?

You can do a lot of the trench for the pipe loop yourself, if your adept at groundwork, that is for a surface laid system, but you require a sizable area of free ground in which to lay this.
An alternative is the borehole system which is installed vertically, these are a bit more common for domestic properties due to the land requirements of the other, but require the specialist equipment for boring the hole and installing the the heat exchange pipework.
So read up on land required to lay a say a 11 Kw system and or get a test bore done for the vertical system, and please don't be taken in by all the sales patter that surrounds this market, like solar/double glazing salesmen, they will tell you any outlandish nonsense just to make a sale.
Ground source heat exchange is not for every situation, but if you can be patient it will not only repay you, but the whole environment around...pinenot :)
 
a well run well set up system will just about have the same running costs as the equivalent gas
a badly set up system will cost more

trying to beat rising gas prices is unlikely to work as electric prices follow gas prices to some extent
your solar panels may offset this to some extent but unless your system is spot on and you get the 3/1 ratio[3kw off energy for every kw off electricity used]you will be worse off
 
It would be using a bore hole ...and it is feasible ...just a heck of a lot of money!
Obviously the returns I am being given by the potential installers would be fantastic -mainly because of the RHI payments...but...
I know for the Solar PV - only had it in for a few months and I'm not living there yet ....I didn't believe the figures on the returns... and I have a feeling I'm right.
In FIT payments I have 'made' more money than I would have earned interest on the capital sum -fantastic - but this is over a very good summer and not enough to pay back my investment...early days I know...
It will always be hard to know how much of a saving on the bills because the background use of the house is higher than when I bought it (security lights, an alarm permanently on, hard wired smoke alarms etc) - and obviously when there are people in doing work it sends the usage right up - I did mow my two lawns for 'free' (without the meter going up the other day) ... :D
I think we need real independent advice about these things ...the installer I am looking at isn't being dishonest with his figures - is just very enthusiastic - great but I can't afford to get this wrong and lose that kind of money!
 
You might want to look into air seal possibilities for the property (Passivhaus standard) and ventilation heat recovery, this could work out a whole lot more economically viable, if your are having works done say around windows and door for instance. By mechanically venting the house via a heat exchange unit, figures up to 92% recovery are claimed, so even if that's a bit optimistic and a fig lets say 80% more achievable, depending on installation cost, this could prove a good choice also or instead of. Units for your size of house could be got for as little as £500 > £600 however the air sealing could cost a whole lot more.
Channel 4 did a bit on it, here's a link - http://www.channel4.com/4homes/diy/plumbing-heating/heat-recovery-ventilation-systems ...pinenot :)
 
Was thinking about Solar Thermal -but now even with RHI payments thinking I will never get my money back ....

Solar thermal for hot water is pretty much the most cost effective green energy thing you can do and as far as I can tell, about the only one likely to pay for itself in savings. It's DIYable too for not much more than a grand for a basic system if you have plumbing skills.

Not sure whether it's bad form to mention other forums but you might find it useful to visit here:
http://www.navitron.org.uk/forum/
 
As I understand it hot water only costs me £100 ish per year, solar thermal will cover 50-60% of that...so even DIY at £1000 will take 17-20yrs or so to make it back (And I would need a new boiler...so it will be about £1k more than that )
Worse - even though gas prices will increase - my children will be leaving home - so we will use less hot water and therefore our savings per year will go down....
To get the RHI payments you need to get someone (registered) to fit it for you ...have been quoted just over £5k (plus new boiler) - the RHI will be about £600 per year for 7 years - so £4200 - leaving the £1000 over 17 years again...
Before they announced they were taking the £600 RHPP grant off the RHI payments it just about stacked up ...now it doesn't (That £600 is 10 years savings!)
And I have an interest free loan in place from the EST to do the Solar thermal - or it really wouldn't have made sense ...

Don't want to make money - just cover my costs and think I might be dead before I do!
Have vaguely looked at that forum before ...will go and investigate some more...
 

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