On May 25, 8:53*am, "Dave Liquorice"
wrote:
On Fri, 25 May 2012 01:22:37 +0100,www.GymRatZ.co.ukwrote:
There is no reason why one couldn't install a larger collector but
what do you do with all that heat in the summer when you have no
space heating requiremen?

Ah well I was also thinking about that one earlier...
The front garden/drive etc could be used as an Interseasonal Thermal
Store.

Do the maths. To store a useful amount of heat you will need a big
store and lots of insulation. When planning the system here I did
half look at how big a store would need to be to supply a days heat.
I think it came out at about 1500l of water at 90C. So to store just
a months worth of heat it's getting a bit big...

I know of a system with ground source heat pump and solar thermal. If
the solar thermal gets the store to it's maximum safe temperature it
dumps the any excess heat into the ground but having thought about it
that is just a heat sink the heat won't stay there 'till the winter
to be pumped back out.

--
Cheers
Dave.

Exactly so. A passive house need only get 5% of it's energy from non
solar sources. So that much expense for active heating makes no sense
at all.

Another point is that the heat has leaked away by the time you need
it.