Ground heating project

[Kevin Lotzof]

We are in the process of renovating an old farmhouse and adjoining barn, piggery and stable block converting it all into living accommodation. In all the floor space is about 7000sqft. We were thinking of installing ground heating to heat the property. We have a dam on the property which is approx. 67m x 37m in size with depths between 1-2m

 

My questions are

1) Is the dam big enough to provide the piping required for the heating.

 

2) How much should a project like this cost?

[Nickfromwales]

Hi. Have you the necessary permissions for abstraction?

[Marvin]

8 minutes ago, Nickfromwales said:

Hi. Have you the necessary permissions for abstraction?

Didn't realise you required a licence to abstract heat from your water on your property, assuming a closed loop ground source heat pump system!

 

[SteamyTea]

1 hour ago, Kevin Lotzof said:

67m x 37m in size with depths between 1-2m

That will be around 3700 m³ of water.

Taking a worse case scenario of the water being at 4°C, and allowing for a 2°C drop in temperature i.e. taking out half the energy, That will be about 15.5 GJ.

So about 4.3 MWh, so quite a lot, just a little lower than the total energy required by my house for a year (but I have a stupidly small house).

 

How is this pond refilled?

[ProDave]

52 minutes ago, SteamyTea said:

Taking a worse case scenario of the water being at 4°C, and allowing for a 2°C drop in temperature i.e. taking out half the energy,

But you know reducing water from 4C to 2C does not take out "half its energy"

[SteamyTea]

3 minutes ago, ProDave said:

But you know reducing water from 4C to 2C does not take out "half its energy"

Depends how deep into quantum physics you want to go.

And phase change.

[saveasteading]

If the water is cooled by 2 deg it is then heated again by the ground underneath, perhaps some nice rotting going on at the bottom, and the inflow of water (dam not pond)

4 deg is going to be midwinter, so really is a worst case, and don't they quote heat exchangers down to -35C?

 

In summer it will recharge  to say 20C.

 

Sounds like a good idea, especially if there is a significant flow of water,  but I can't do the sums for it.

[Kevin Lotzof]

It is naturally filled pond. We also have 300m of river running thru the property

[SteamyTea]

1 minute ago, Kevin Lotzof said:

We also have 300m of river running thru the property

you would be better off using that, as long as the flow is good.

[Nickfromwales]

20 hours ago, Marvin said:

Didn't realise you required a licence to abstract heat from your water on your property, assuming a closed loop ground source heat pump system!

 

It’s mentioned as a dam. Therefore flowing water, not a stagnant lake or pond etc. Flowing water = abstraction license afaik as you’re affecting the downstream ‘condition’ of the water. Further reducing temps in winter can have adverse affects on nature / pond life etc so best to check ( at least ) before going down this route. 

Edited October 18, 2021 by Nickfromwales
Small phone and big thumbs.

[TonyT]

Have a look at the old Navitron website, Nowty did this with a culvert under his house, copper coils submerged. Worked for him 

[Nickfromwales]

On 18/10/2021 at 11:22, TonyT said:

Have a look at the old Navitron website, Nowty did this with a culvert under his house, copper coils submerged. Worked for him 

Were the coils running a brine with glycol ( antifreeze ) inhibitor in it? 

[TonyT]

Can’t remember think it was some vegetable based product ( in case of a leak) 

 

it was 15 pages, it also discussed his PV, and Lead acid battery then move to Lion batteries.

 

 

[TonyT]

Tried to find the thread, but looks like the site is no longer there, the info isn’t on the new website that a lot of people moved to.

 

maybe the way back machine?

[saveasteading]

1 hour ago, TonyT said:

some vegetable based product ( in case of a leak) 

Are we doing puns now?