Following my posting re reverse thermostat, I have been wondering just what
ideas the collective brains on this group could come up with for
Greenhouse/poly tunnel heating.
We get a lot of questions re Gas , electric or paraffin heating, but surely
we can come up with something free/cheep and useable.

I seem to remember talk of having bottles of water with washing soda in
solution in them, the idea being that when the temp dropped to below 50 then
the soda would crystallize giving off heat, and when the water was over
about 60 then the soda would absorb heat as it went back into solution.
Now have this in tanks with some sort of heat exchanger taking heat from the
top of the house in the day and heating the tanks.........


--
David Hill
Abacus nurseries
www.abacus-nurseries.co.uk