Rhiannon Macfie Miller writes
Having had a poor germination rate (30%) of tomatoes both this year in
my conservatory and last year on my dining room windowsill, I was
wondering whether a more constant temperature would help. I was
thinking about a smallish heated propagator. Are there any such things
available that run on solar power or are otherwise environmentally neutral?

It's a difficult question, isn't it? The amount of electricity they use
is small, and I wonder how it relates to the energy used in their
construction.

--
Kay