The message
from "David Hill" contains these
words:

And to think I thought we might get some lateral thinking going on the
subject.
I know we wont be able to get all our heat in Dec. Jan for nothing but oct,
nov , Feb March and april we should be able to generate enough free heat to
carry through most nights.
No talk of Bio digesters to use grass clippings, poultry manure etc. to
produce gas for our heaters
Looks as if I will just have to press on on my own.
Thanks anyway.

The trouble with biogas digesters is that you need a high volume of
digestible stuff to make them work.

They need some heating in this climate, especially in the winter, so a
small unit could draw more energy than it produced.

You need to make a scrubber to remove the carbon dioxide from the
resulting gases, and a drier for the clean methane.

You need storage for the gas.

Assuming you get that far, you have to guard against sudden drops in
temperature, or the system sucks air in when the gas within contracts.

One of my friends used to be a Mandarin in the Agricultural Research
Council. He and a group of boffins were invited to see one of these
systems working on a big dairy farm. This was installed by a specialist
company: it wan't a DIY job.

Cold snap.

Urgent phone call on the morning of the visit - Don't come, it's blown
up! (And we're not talking 'inflated', either.)

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