Ground source heat

[kneedeep]

I've got 15 ac field in front of house, 12 inch sandy soil ,18 inches silver sand , then clay.
Mate has a trencher.
House has no heating system, solid floors downstairs that need replacing(gonna put underfloor heating in while I'm at it).
10kw solar panels on a shed roof .
Does a ground source heat pump system stack up?
@ Tayside

 

[Farmer_Joe]

What manufacturer is your heat pump @Farmer_Joe

Its made by or branded as themia but i believe they have been bought up by danfoss, which i believe are are large manufacturer chillier countries where they were first developed!

 

[Grassman]

I've got 15 ac field in front of house, 12 inch sandy soil ,18 inches silver sand , then clay.
Mate has a trencher.
House has no heating system, solid floors downstairs that need replacing(gonna put underfloor heating in while I'm at it).
10kw solar panels on a shed roof .
Does a ground source heat pump system stack up?
@ Tayside

It does with the rhi payments. Get some quotes to see the figures

 

[beltbreaker]

Chartered Surveyor neighbour who used to be a great advocate of his system (installed 7 years) is now fitting an oil combi due to poor reliability. Farmer neighbour doing the same as it has been under specced and using a lot of electricity. Both from the same company which has now gone tits up. Know of 2 or 3 more which have supposedly been fine. Get multi recommendations from other users of decent companies. Alternatively fit oil but leave space and ducts for all the pipes and cables to run the system and fit it when oil goes back up.

Cheers BB

 

[Grassman]

Chartered Surveyor neighbour who used to be a great advocate of his system (installed 7 years) is now fitting an oil combi due to poor reliability. Farmer neighbour doing the same as it has been under specced and using a lot of electricity. Both from the same company which has now gone tits up. Know of 2 or 3 more which have supposedly been fine. Get multi recommendations from other users of decent companies. Alternatively fit oil but leave space and ducts for all the pipes and cables to run the system and fit it when oil goes back up.

Cheers BB

I am hoping that with the benefit of experience that they fit them correctly nowadays

Must say I'm a little unsure now the price of oil is so low. This is just what the oil producers want though. Making alternative energy sources unviable is their aim. Kerosene is now down to the mid 20 pence a litre and will go lower. Will it stay low for 10 years? Who knows but I doubt it. Running heating with oil is probably less than half the cost of a few years ago. Must say it's tempting to just install oil boiler and put ground source off for a few years.

 

[ashelton]

If your thinking of Ground heat source installed possibly our CT150 may be of some interest to you.

Above is a picture of our CT150 installing GHS pipe work.
For more information please visit www.sheltonsdrainage.com or you can give us a call on either 01507 578288 / 07734531227.

 

[SmeatonWoodEnergy]

We often compare Biomass with Ground Source for our clients (we offer both) vast majority go with Biomass due to the financial outlay required for Ground Source and the need for three phase on a decent sized system. Also exposure to electricity costs on Ground Source is significant with 10% increases over the last 10 years as well as predictions of wholesale prices significantly jumping due to incoming distribution charges and Nuclear deals.

 

[Grassman]

We often compare Biomass with Ground Source for our clients (we offer both) vast majority go with Biomass due to the financial outlay required for Ground Source and the need for three phase on a decent sized system. Also exposure to electricity costs on Ground Source is significant with 10% increases over the last 10 years as well as predictions of wholesale prices significantly jumping due to incoming distribution charges and Nuclear deals.

@SmeatonWoodEnergy why do you need 3 phase electric with ground source heating?
Do biomass boilers not use electric?

 

[ashelton]

Take a look at this.

 

[SmeatonWoodEnergy]

@SmeatonWoodEnergy why do you need 3 phase electric with ground source heating?
Do biomass boilers not use electric?

Hi Grassman, typically small heat pumps don't require three phase, however anything of a commercial scale will require three phase. Biomass can operate off single phase. Hope this helps.

 

[young&keen]

@kneedeep how you get on to looking into ground source? Can you still get feed in tariff for it? Am just looking for options to heat a bungalow!

 

[Still Farming]

how good are they these days ? As a while ago these systems used more energy to run than what was saved/used ???

 

[Grassman]

how good are they these days ? As a while ago these systems used more energy to run than what was saved/used ???

How long ago was that?
That must of been a badly installed or designed system.

 

[Still Farming]

How long ago was that?
That must of been a badly installed or designed system.

10yrs maybe - bound to be huge difference now along with the air to air type exchangers ?

 

[Grassman]

If correctly installed ground source is very efficient. I think you put about 1kw of electric into the system and get 4 kw of heat out. Air source is a lot less efficient but still gives a positive return.
The rhi payments are good for Ground source unlike solar which is realistically a waste of time now.
I am just about to get mine installed if the field ever dries up!

 

[kneedeep]

P

 

[akaPABLO01]

ground source and air source are very good when underfloor heating is implemented. They make the systems upto 25% more efficient compared to rads. It's all about insulation and radiating the heat around the property. You'll find both of these poor if you put them on an existing wet system replacing say a boiler. If you go down this route and your in a 100 year old farm house with solid walls you should get a log burner. These technologies have coefficient ratings usually 3:1 this means the system will produce 3kW of heat for every 1kW of electricity used.

 

[Oldwalls]

We have recently installed a Nibe system for our 4 bedroom farmhouse, a 12kw heat pump with 600m of pipe in the field next to the house. We had an oil fired Rayburn in the kitchen and a coal fire in the front room, along with Economy seven electric storage heaters in most of the other rooms. We installed fan assisted radiators in all rooms, with heaters in the office, upstairs hallway and bathroom for the first time.

After a week of running, our house has never been warmer with rooms at a constant 19-21 C depending on the size of radiator and the speed of the fans and settings of the radiators. The hot water is at 50 C without the need for any emersion heater.

It appears that the heat pump is taking around 25kw hours to run per day, therefore a cost of approx. £2.50 per day, but there is a saving within the house on the economy 7 electric of at least half of that cost. We could increase the savings by installing another tank to store hot water heated by our solar panels through the day for when we draw off hot water when the sun is not shining. We have turned the Rayburn off and not had a fire in the front room all week. The wife is saying some rooms are too hot!!

Overall we should be on track to make at least the savings on fuel that were estimated when we were obtaining quotes, this was approx. £1500 per year.

The total cost was £17k for the heat pump system and the new radiator system, the RHI payments are estimated to be £20,000 over seven years, which will cover the capital and interest on a loan over the same period, therefore we should have a warmer house & cheaper power costs, along with a system that should have minimal regular maintenance.

From my enquiries, a number of the bad experiences in the past have been from systems that have had inadequate capacity in the heat pump and or length of pipework, and some people have either tried using standard radiators at low temperatures or tried to get the heat pump to work at 70-80 C which then becomes very expensive in extra demand for emersion heaters or the pump running constantly.

Heat pumps work best with under floor heating systems, but very good results can be had with fan assisted radiators, which are approx. the same size as standard rads

I hope this helps

 

[kneedeep]

Thanks for the comprehensive report.

 

[Mur Huwcun]

Hows everyone getting on with their GSHPs this winter? Ours seemed to be working hard over the weekend and running more than usual. About 14 hrs use over 24hrs. Brine in and brine out temp dropped aswell which is not what I was expecting during first month of winter. What’s everyone elses loops running temp? Over weekend this one dropped down to around 6.5 degree in and down as low as 1.2 degree on the out line. This was near Mid last winter running temp. 8kw pump ond just over 400m of loop.