Solar Thermal Store V Immersion Advice

[enfable]

I as wondering if anyone knew about thermal stores?

I have 3.98kw solar panels and a heat only boiler plus a standard immersion heater which the solar panels heat up during the day. My house has 2 electric showers and 3 gravity fed showers plus a bath. Currently my solar panels do not heat up my central heating which a thermal store could.

My questions are:
1) would it be cost effective for me to have a thermal store fitted as this would heat up my central heating too?
2) Would a 300L thermal store system be enough for my needs or should I look at something bigger?
3) Which brands would offer the best value for money?
4) Is there anything else I could consider?

Any advice would be appreciated.

[The Builder]

Not my area at all I'm afraid, but I do have one thought.

If your panels are heating the immersion all day, plus one or more gravity showers, then I can't imagine there will be much if any panel capacity left to fill a thermal store.

[enfable]

I would be replacing the immersion heater with the thermal store. That way I should be able to use the TS to heat my central heating. I am not sure if that would be cost effective as my solar panels currently heat my immersion.

[The Builder]

I'm afraid I may be showing my ignorance here enfable, but isn't a TS simply a battery to store electricity. I don't see how it could heat water without an immersion element to power.

[kuiperbelt]

/but isn't a TS simply a battery to store electricity. /

I think you might be confusing this with those solar panels which work on transferring the energy of the sun into photo-voltaic cells.

With a TS we require the other type of solar panel. Note, the TS is quite versatile too. They can be supplied by a log burner, oil or gas boiler.

In the Solar 'thermal' Panel scenario, there are tubes carrying water which are integral to the solar panel construction. Thus the water in the tubes heat up due to the action of physical parabolic reflectors which surround the copper carrying water tubes within the Solar Panel. This hot water is then passed into the TS.

You're right when you say TS acts as a battery. But it's a battery which stores thermal energy i.e., Hot Water NOT like a conventional electrical battery which stores Chemical energy, which would be the scenario you were thinking of with the other type of Solar panel.

Note, the TS transfers its energy to a mains fed cold water supply via an heat exchang plate when water is demanded.

Hope this helps!

[The Builder]

Thanks for that, kuiper.

I hope that helps enfable out :o)

[enfable]

Yes, the thermal store I am considering is this https://www.gledhill.net/products/alternative-energy/torrent-stainless-sp-sol
The water in the store can be heated by solar, log burner or electric. This can then be used for the household hot water and central heating. It has an immersion heater built in to it.
I already heat my immersion heater from my solar vis my households electricity. I think the immersion in the thermal store would be more efficient than the immersion I currently have. But it’s still a large outlay to buy and have fitted. I not not currently have a log burner.
I was wondering if anyone had an idea in the payback time would likely be? And if a 300L would be enough for my needs.