Ok, a little more detail.
Intention: A fan pushing cool air through a network of pipes arranged like a heat exchanger in a compost heap so the air is warmed and the warmer air vents into the chosen space ie a greenhouse resulting in a warming effect.
Please, please don't critique pipe bore or air flow or fan volume or heat exchange design or smell just yet, that's all for the future. Firstly, I need to know if a huge pile of manure, appropriately insulated, layered and 'designed' will generate enough heat from 1st December through to 30th April with minimal upkeep.
I know a compost pile gets hot, but for how long and what's the 'fuel'? Does the 'fuel need to be placed in the middle, spread throughout, topped up, urinated on, insulated, given air, given water and so on.
Remember that I need to generate (free) heat, NOT produce quality compost. If that happens it's just a bonus.
I knew someone would pick up the Tiswas link, sorry to disappoint. Did you shout out 'Compost Coorrrrner' when you read it? I did when I wrote it
