Jeff
I'm surprised you haven't mentioned hotbeds for greenhouse heating. Those
old pit houses were nearly alway dependent on manure as their main heat
source (where they didn't have steam pipes and a wage slave on the end of a
shovel). They really work for me. Heat the house nicely in spring and their
heat creation goes down as the weather warms up - perfect. I use straw
bale sides and salvaged glass windows on top inside a conventional
polythene tunnel. (No space in lean to conservatory which gets waste heat
from house and my 30 foot greenhouse met one gale too many last autumn - we
haven't got up the courage to start disassembling the remains yet. It will
take scaffolding to do it and stay alive and there are too many other
spring jobs.)
kathryn
