Changing the use of solar panels?

murphydog999

This is a completely new area for me so I'll try and be brief!

A house we are looking at has a solar heated swimming pool. We are considering filling in the pool, so the question would be the feasibility of using the panels (owned by the owner, 7 of them, 5 yrs old, situated on a garage roof) for home use? (The house currently uses oil for heating but also has a huge aga.)

There will need to be some renovations so not adverse to a few changes. Any ideas or suggestions gratefully received

zeupater

murphydog999 wrote: »

This is a completely new area for me so I'll try and be brief!

A house we are looking at has a solar heated swimming pool. We are considering filling in the pool, so the question would be the feasibility of using the panels (owned by the owner, 7 of them, 5 yrs old, situated on a garage roof) for home use? (The house currently uses oil for heating but also has a huge aga.)

There will need to be some renovations so not adverse to a few changes. Any ideas or suggestions gratefully received

Hi

There's probably nothing to prevent you using the panels to run an U/F heating loop to provide a little heat in the spring/autumn and therefore run the oil heating for fewer days .... when you put the loop in design it to allow for possible future change such as a GSHP so that you don't need to waste/duplicate work ...

Everything really depends on how large the panels are, their orientation and how much the heating circuit changes would cost ..

HTH
Z

Fruit_and_Nut_Case

murphydog999 wrote: »

This is a completely new area for me so I'll try and be brief!

A house we are looking at has a solar heated swimming pool. We are considering filling in the pool, so the question would be the feasibility of using the panels (owned by the owner, 7 of them, 5 yrs old, situated on a garage roof) for home use? (The house currently uses oil for heating but also has a huge aga.)

There will need to be some renovations so not adverse to a few changes. Any ideas or suggestions gratefully received

Just to be clear... Are they solar PV panels or solar water heating panels?

murphydog999

That I don't know, I would hazard a guess that they are not PV.

thenudeone

murphydog999 wrote: »

That I don't know, I would hazard a guess that they are not PV.

I know of solar PV being bought almost entirely to run an ASHP for a pool (plus FITs)

So OP would need to check.

Solar thermal for a pool is designed to heat a large body of water by a small amount. A domestic solar thermal system has the opposite requirements, Pool Solar panels may be little more than black rubber tubes, whilst domestic solar thermal may be vacuum sealed in cases with reflective backs. So panels designed for one use aren't ideal for the other. They may not survive the chemicals used in the other type of system.

However, if the panels are already installed, it's certainly worth investigating. You probably need a specialist solar thermal installer to have a look (or even a chat on the phone).

zeupater

thenudeone wrote: »

I know of solar PV being bought almost entirely to run an ASHP for a pool (plus FITs)

So OP would need to check.

Solar thermal for a pool is designed to heat a large body of water by a small amount. A domestic solar thermal system has the opposite requirements, Pool Solar panels may be little more than black rubber tubes, whilst domestic solar thermal may be vacuum sealed in cases with reflective backs. So panels designed for one use aren't ideal for the other. They may not survive the chemicals used in the other type of system.

However, if the panels are already installed, it's certainly worth investigating. You probably need a specialist solar thermal installer to have a look (or even a chat on the phone).

Hi

Agree with above .... that's why I mentioned U/F heating, this being a reasonable way to utilise relatively low temperature gain in the heating season .....

My only real worry would (depending on the panel type/construction) be around the system stagnation in the summer when there is no heating demand ... immediate solutions which come to mind are to either leave the pool in to act as a heat dump, or, if GSHP is considered, utilise the solar panels to recharge the ground temperature by utilising the ground loop when household heat isn't required.

HTH
Z

Martyn1981

zeupater wrote: »

Hi
or, if GSHP is considered, utilise the solar panels to recharge the ground temperature by utilising the ground loop when household heat isn't required.

Z

Z, you've got me thinking there. Though I'll admit to knowing next to nothing on GSHP. If you're heating the ground, do you need the area to be relatively stable and dry?

I'm thinking that earth and moisture would disperse the summer heat storage.

So the obvious (???) next step would be to bury the ground loop in a dry piece of land full of stone or similar. Now if only there was a ready dug hole, that was already tanked, and not wanted, in which the loops could be buried. Can you see where I'm going with this? Would it work?

Mart.

Cardew

A domestic swimming pool would not be large enough or deep enough for a GSHP loop.

murphydog999

It is a 40ft pool if that helps?

zeupater

Martyn1981 wrote: »

Z, you've got me thinking there. Though I'll admit to knowing next to nothing on GSHP. If you're heating the ground, do you need the area to be relatively stable and dry?

I'm thinking that earth and moisture would disperse the summer heat storage.

So the obvious (???) next step would be to bury the ground loop in a dry piece of land full of stone or similar. Now if only there was a ready dug hole, that was already tanked, and not wanted, in which the loops could be buried. Can you see where I'm going with this? Would it work?

Mart.

Hi

there have been discussions on the effect of water table and water migration on a ground loop on this forum (& others) before & consensus seems to be that a general water migration down a slope containing a groundloop would be beneficial to the replenishment of ground heat increasing the efficiency of the GSHP, especially noticeable later in the heating season (at least in theory!). GSHPs aren't really geothermal systems, they actually collect the solar energy absorbed by the ground during the summer. With earth being a pretty decent insulating material it would make a lot of sense to simply dump summer solar energy below the surface where it wouldn't be open to direct radiated loss to the sky at night .... anything which increases the ground temperature recovery rate at the depth of the loop can only be beneficial.

Regarding the pool ... It really is an interesting thought. I'd guess that a 40' pool would have a storage capacity of somewhere around 120kWh.t per degreeC in itself, but raising the temperature of the contents would also raise the temperature of the surrounding ground, possibly giving an eventual 2x additional boost to the effective storage capacity, so somewhere around 350kWh/degC raised could be the total available. You would however need to insulate the pool surface really well to prevent any collected heat from escaping to the atmosphere (therefore allowing it to soak into the surrounding ground), this being far more than a standard pool cover, possibly an insulated structure over 40' long - so pretty expensive unless it's a DIY carpentry job. Someone, somewhere must have tried something similar when looking at interseasonal storage, however, my guess is that the heavily insulated cover structure would far outweigh the cost of a groundloop and the complete system could only provide at a maximum what the existing panels could collect (guess ~5000-7000 kWh.t ?) - I'd also guess that the existing pool is pretty close to the property, therefore aesthetics come into play and the cover couldn't simply look like a rough & low garden shed ... :cool:

HTH
Z

murphydog999

:undecided Hmmmmm! Thanks chaps, interesting but REALLY confusing! If we go for the place, I think I'll ask for the company's details and see if indeed they can be integrated somehow - they seem such a waste otherwise.

Are they saleable at all?