The message
from "Franz Heymann" contains these words:

It's called solar heating with heat storage. Or if not using heat from the
sun heat pump systems can take it from the environment directly.

But unfortunately the price of a heat pump is so high that the money spent
in amortising it might as well be spent buying electricity ot paraffin.

You can make a heat pump for no cost at all, or very little - assuming
you can find someone with an old freezer they don't want.

--
Rusty
Open the creaking gate to make a horrid.squeak, then lower the foobar.
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