[lightyears]

made a solar heating/cooling system for there greenhouses?

http://www.reuk.co.uk/Solar-Greenhouse-Heat-Sink.htm

i was reading around and came acrossed this, does it really work? has any ever implemented it in real life? the most expensive bit is the solar panel(39.99 on ebay) the rest i have. any ideas?

[nobby]

dont minde a bit of diy but that looks like hard work

[lightyears]

im thinking about the saving in my cash on parafin if it works. plus the world and that 

[SG6]

It was on the BBC program. Looked simple enough. Take warm air from the top and push it through something that would retain the heat and release it slowly.
As it say the idea is simply to add a little heat at night using the spare heat from the day.

Isn't that what night storage radiators were?

You would need to insulate the mass that you heat up from the ground or else heat would transfer out via that route.

Suspect that the biggest problem is that it needs there to be "spare" heat at the top and during the colder months there is not much of it. Case of cold days and short days.

[Stripey_cat]

It should help even out the temperature, even in winter (in fact, given that a yard underground is often warmer than the surface anyway...).  Has anyone looked at the cheap solar-powered lights that places sell to see if you'd get enough power to run a fan from one of those?