The Accidental Smallholder Forum

Smallholding => Renewables => Topic started by: cloddopper on March 26, 2018, 02:35:12 pm

Title: Ground Source Heat Pumps ? Up to date advice please .
Post by: cloddopper on March 26, 2018, 02:35:12 pm
I belong to a charitable organisation that provides a point of interest , contact , friendship & woodworking etc for all manner of people who tend not to have lots of family or friends around them .

We've been allowed to have premises three large rooms in an an old redundant junior school at a peppercorn rent but need to have some sort of heating as this last two months has seen us get the water pipes inside thick insulation frozen  .
 We have the FOC use of a professional communities development officer ( CDO ) who is a  BA with honours  , to help us with anything related to developing our group especially doing paperwork .
They have made enquiries with several big energy providers who run schemes for alternative low carbon  energy about installing bulk wood pellet heating under the terms of one of their schemes . 

Now I realise that this burner set up may not be the best way forward because of the higher costs involved for fuel plus a GSHP can be set to run on a time clocked working week etc or brought into being at preset low temperatures ..

Rosemary , can you tell me what sort of KW of heat your system produces & roughly how much did it cost to install please ? do you have any figures that will indicate how may KW of electricity it took you to generate your heat ?

As a result of the freeze up we had a 3/4 inch pipe burst some time over a Friday to Monday when the premises were empty . almost six inches of water was removed by the fire brigade team that came to help out . 

The dehumidifiers we've hired to dry out the parquet flooring  keep freezing up when the air temperatures  drop to 4 oC or less inside the building . so a light residual heat  seems to be something needed when the premises is vacant

Anyone else who has input is welcome to post , for the more info I can gather the better I can talk to the C DO .
Title: Re: GSHP's
Post by: landroverroy on March 26, 2018, 04:06:00 pm
Just a thought Cloddopper - might be an idea to title your post "ground source heat pump" as it doesn't obviously spring to mind from the initials. I didn't recognise it, but looked it up. Some people might just pass on and not realise. 
Anyway, I just wanted to say that I had a pellet boiler installed free at a house that has no natural gas. The boiler belongs to the company who installed it for 7 years. During that time they service it and claim the subsidy, and after that time it becomes mine.  It's a great source of controllable heat and I would recommend it.
Title: Re: GSHP's
Post by: Womble on March 26, 2018, 05:19:58 pm
a GSHP can be set to run on a time clocked working week etc or brought into being at preset low temperatures.

I'm not trying to sway you one way or the other Cloddopper, but exactly the same is true of a pellet boiler. Ours has two control loops - the first one fires the boiler whenever required to keep a thermal store (big tank of water) at 70 degC. The second one controls a secondary recirculation pump, providing heat to the radiators or hot water cylinder whenever a standard timer / thermostat calls for it.

a light residual heat  seems to be something needed when the premises is vacant

Now, that is what a heat pump is really good at - low level constant heat. So if your building is being used all the time and is well insulated, a heat pump could be really good. However, if you just want a low level "don't let the building freeze" sort of heat for most of the time, but then heat me up to 18 degC for a meeting in the evening, a pellet boiler would give you more oomph when required.

Does that help / make sense?
Title: Re: GSHP's
Post by: Dan on March 27, 2018, 08:00:57 am
Rosemary , can you tell me what sort of KW of heat your system produces & roughly how much did it cost to install please ? do you have any figures that will indicate how may KW of electricity it took you to generate your heat ?

I've attached the energy calculations that were done for us before we installed our heat pump. We've never done any running cost calculations since.

Our heat pump was £9k to install in 2010 (Nibe 1245), and we got a grant of £2750 towards it that was available at the time.

HTH, happy to answer any questions.
Title: Re: GSHP's
Post by: Maysie on March 27, 2018, 02:41:56 pm


Now, that is what a heat pump is really good at - low level constant heat. So if your building is being used all the time and is well insulated, a heat pump could be really good. However, if you just want a low level "don't let the building freeze" sort of heat for most of the time, but then heat me up to 18 degC for a meeting in the evening, a pellet boiler would give you more oomph when required.

I am looking into replacing our oil-fired boiler system at the moment and this is exactly the advice I have received. 

Our old farmhouse if not very well insulated, so the low level of heat generated by heat-pump tech would not be up to the job for our situation, so a pellet boiler is what we are looking into.  The up-front cost is not cheap though, even if some of it does come back as a RHI payment over the 7 years, you still have to find the cash in the first place.  It is approx 5x the cost of a straight oil boiler replacement. 
Title: Re: GSHP's
Post by: landroverroy on March 27, 2018, 04:00:12 pm
Look up grants Maysie.
As I said above - I got a pellet boiler installed free of charge in a house that had no natural gas supply. The firm who installed it gets the RHI and services the boiler for the first 7 years, and after that the boiler is mine. Absolutely no cost to me at all.
Title: Re: GSHP's
Post by: Maysie on March 27, 2018, 05:14:24 pm
LRR, do you have any pointers? 

I have spoken with the Energy Savings Trust, Energy Saving Advice Service, local council energy advisor and so far there has been absolutely no mention of grants as I am not on benefits of any kind. 
Title: Re: GSHP's
Post by: Womble on March 27, 2018, 05:40:33 pm
[member=175813]Maysie[/member] ,  Check out RHI (Renewable Heat Incentive). It's not dependent on any other benefits.

There are two classes - domestic and commercial. The commercial one pays you based on the heat you produce (it's measured), whilst the domestic one pays a grant based on the size of boiler you have installed. This is governed by the size calculated by an energy assessor. This money is paid to you quarterly for seven years, and then you're on your own.

At its most basic, you have to shell out the cash for the installation yourself, but then the payments also come to you. However, there are also financing schemes like Landroverroy's, whereby you don't buy the boiler yourself, but then neither do you get the payments.

Beware, there is lots of skullduggery afoot in how these systems are calculated and sold. According to the companies we dealt with, we stood to gain about 3x the cost of the boiler back over 7 years when compared with our existing system. When I looked at those claims critically, as a qualified engineer, I found them to be total rubbish. The reality was something nearer to "The running costs for the new system will be almost the same as for your old system. You spend £X on a boiler, and over seven years, you'll get back the same amount from the government. Basically you get the boiler for free."

The amount of the RHI payments has decreased since then, making it less attractive. However, if you're going to be getting a new boiler ANYWAY, definitely think about getting one that qualifies for RHI, since it will still cover the extra cost of pellets etc, when compared with for instance a new oil boiler.
Title: Re: GSHP's
Post by: Maysie on March 28, 2018, 10:02:56 am
Hi Womble
It is the RHI scheme that I am looking at, but we are being quoted £7k for a new oil fired boiler and new tank installation, but £18-25k for a pellet system.  We will qualify for the full (capped) RHI repayment of around £11.2k over the 7 years, but still have to find the £18-25k in the first place.   
Title: Re: GSHP's
Post by: Womble on March 28, 2018, 02:21:00 pm
Yup! And there's your dilemma.

The RHI scheme is intended to level the playing field to make up the difference between oil and renewables. In your case, it looks as though it's doing exactly that (18-7 = 11, which is pretty much what your RHI payments will come to).

After that, it just comes down to what will suit you best, what finance is available to you, and how you feel about so-called green options.

In our case, we were able to borrow cheaply on our mortgage to buy the boiler, but I appreciate that might not always be either an option or a good idea.
Title: Re: GSHP's
Post by: landroverroy on March 28, 2018, 10:26:04 pm
LRR, do you have any pointers? 

I have spoken with the Energy Savings Trust, Energy Saving Advice Service, local council energy advisor and so far there has been absolutely no mention of grants as I am not on benefits of any kind.


You don't need to be on benefits. I did it through a firm called A Shade Greener, who supplied and service the boiler and all ancillaries, at no cost to me. I would recommend them.
Title: Re: GSHP's
Post by: Maysie on March 29, 2018, 09:28:06 am
Thanks LRR
That company seem to be offering solar panels only now, so I guess the pellet boilers may no longer be financially viable for them since the RHI payments have been reduced. 

My total RHI allowance would be £11.2k which just about covers their supply cost of the boiler and hopper,  let alone any installation cost, profit etc for them. 

Sounds like you got a very good deal!  (and I have missed  the boat...)
Title: Re: GSHP's
Post by: pharnorth on March 29, 2018, 09:48:09 am
We missed the boat by doing ours before all the grants and tariffs. We were rewarded with more years of being warm and smug though. It was a bit like swimming the Channel only to arrive on the beach as a pleasure cruiser laiden with canapies and cocktails set off.

Anyway, point being the grants and tariffs come and go so while you may have missed that boat there may well be others if you have the time and patience.
Title: Re: Ground Source Heat Pumps ? Up to date advice please .
Post by: cloddopper on April 02, 2018, 05:16:46 pm
Thanks guys & gals ,
 That's exactly what I wa looking for .. a general starting point when I can put the idea forth to the community development officer & councilors  .
 
 The main activity of the building will be a  bi or tri weekly  use by up to seven or more social groups . Ie  Scouts& guides , a slimming club, use of the building for a travelling bank , boot sales for recognised charities , our men's shed ( 3 or more sessions a week currently ) A local railway society meeting place but not equipment storage or workshop . Finally weekly session for citizens advice &  a bi weekly social playgroup event  ( we have a fully enclosed front yard full of  some reasonable play frames etc. )  If we eventually get the whole of the old school up with a massive playground & three large all weather  rain shelters up  & running we hope to turn it into a large thriving community benefit , supported in part by locals & by the Welsh government in what they term an area of great social deprivation & unemployment .

There is no mains gas here , we are in the back of beyond . 
Title: Re: Ground Source Heat Pumps ? Up to date advice please .
Post by: SallyintNorth on April 02, 2018, 07:43:22 pm
There's quite a bit more to do on an ongoing basis with the pellet boiler - order, stack and tip in the pellets (daily in winter), clean out the jets and ash and so on (weekly.).  GSHP is easy to run once it's in - but the earthworks to instal the slinkies is a major, major project.  And if not done well, can leave you with ground that takes many years to recover.

We use GSHP to heat a number of our homes here, most of which are converted farm buildings.  Small well-insulated homes are well-heated in all but the most extreme of weathers by the GHSP.  Underfloor might struggle to maintain 18C when it's below 0C outside, but the chunky radiators can chuck out a lot of heat.  We did find the water temperature dropped noticeably in the recent very subzero temperatures - but that's a very rare event for us in Cornwall.   

Getting the right pellet boiler is important.  We have one but haven't found the appropriate scenario for it.  It was too much for the two well-insulated homes it was originally installed for and it never generated any RHI payments; moving it to heat three homes proved expensive and the access for unloading pellets was an issue, so we've gone for gas for those houses.  The pellet boiler may be installed to heat the common areas in the farmhouse plus a couple of flats - but it's really quite noisy and we haven't completely decided we can stand that racket in the communal kitchen yet :/

Oh, and our guys here would not bank on there being much usable life left in a 7-year old pellet boiler.  It may go on for 15 years of course, but you might find there's not a lot of life remaining at the end of the 7-year deal.  (Doesn't mean it's a bad deal, just something to take into account.)
Title: Re: Ground Source Heat Pumps ? Up to date advice please .
Post by: cloddopper on April 02, 2018, 11:59:55 pm
Thanks Sally , I realised the seepage of cold snow melt  down to the heat exchanger coils deep in the ground would give a corresponding temperature out put drop .
 
Any idea what sort of vertical depth & diameters we might need to be thinking of for drilled bore holes . There is no way we'd be able or allowed  to rip out 3/4 of an acre of tarmacked playground for deep trenching of the pipes .
Title: Re: Ground Source Heat Pumps ? Up to date advice please .
Post by: Womble on April 03, 2018, 09:35:57 am
Just to respond to some of Sally's points:

Different pellet systems are fed differently. The one we have is fed with 10kg sacks, so the hopper needs filling by hand roughly once a week. Then the ash needs emptying maybe every six months (seriously!). The boiler does all its own cleaning automatically, and gets an annual service by the installer.

My parents' system (more like what you'd want) is fed from a bulk tank that takes about five tonnes of pellets at a time and hence lasts them ages. These are blown in from the roadside. It's no harder to keep an eye on the level in the store than it would be the level on an oil tank.

The noisy times are when it's cleaning (a sort of clanking sound for a minute or so every cycle), and when it fills its little day tank, which sounds a bit like a hoover for a minute twice a day. It's fine in an outbuilding or plant room, but I wouldn't want it in my kitchen, right enough!

One of my concerns over RHI is that some of the equipment offered may not have longevity. We deliberately went for a more expensive Austrian boiler in the hope that it would give a longer service life. My parents' system (pre RHI) has been running for 15 years now without problems.
Title: Re: Ground Source Heat Pumps ? Up to date advice please .
Post by: SallyintNorth on April 03, 2018, 10:51:50 am
I've no knowledge of vertical systems, sorry.  But if you go ahead with yours, please update us - I might put in a plea that we do that next time, rather than trash another of our remaining grazing / hay-making areas!
Title: Re: Ground Source Heat Pumps ? Up to date advice please .
Post by: bazzais on July 09, 2018, 11:33:31 pm
Info on free airsource pumps in Newcastle Emlyn ? Maybe of use ?

https://www.ecofriendlypower.co.uk/ (https://www.ecofriendlypower.co.uk/)
Title: Re: Ground Source Heat Pumps ? Up to date advice please .
Post by: cloddopper on October 17, 2018, 12:41:07 am
I no longer go to the place that was considering the GSHP system but kind of got the idea that they would rush in with the cheapest options of a couple of radiators & a hot tap using a self contained balanced flue combi gas boiler set up that they can get,  as gas has recently been piped to the road running by the building . ( £2.5 K ? )

Thanks for your help guys & gals .