On Mar 27, 2:04 pm, "Clive" wrote:
The "clever" bit would be to have a hot water tank but only use it
for the central heating. It would have two supply circuits, one from
the wet solar panels on a south-facing roof - this would "pre-heat the
water. The second supply circuit would be from the boiler. The idea
being I could collect as much heat as possible on a sunny day on the
solar circuit and top it up with gas-heated water. The tank would need
to be well-insulated to store the heat from a sunny day and release it
in the evening.

So you get the most hot water for heating on the sunniest days when
you are least likely to use it. I think you have it arse about face.
Use solar to augment the hot water which you will use year round.

MBQ