andrew-l wrote:That sounds like an interesting project - I've been looking at something like this to moderate the summer temp in our Polytunnel. Have you got more details? Presumably it's solar-powered?the mad cyclist wrote:Slightly off topic.
In another thread we discussed how modern cheap mass produced items are unreliable, well the small 12v DC fan that I fitted into the pipe leading from the apex of my greenhouse to the heat store below, has now been running almost constantly for three and a half years.
Not bad to say it cost approximately £3.
Andrew, a few pics to show my greenhouse solar heating project.
Power is by an old car battery charged by a solar panel, the charge doesn’t always last the night in winter.
Its seems to works best in spring and summer, by keeping the greenhouse warm on those snicky cold nights.
In winter, a 10 x 8 single glazed greenhouse, exposed to open fields, would take an awful lot of stored heat to keep warm.
I found that a small fan, cut down and fitted inside the pipe, moved a lot more air than a larger fan fitted into a tube and taped to said pipe.
The next part of the project is to construct some kind of solar collector, any suggestions?
Rainbow at no extra charge
