Okay I built a small version of this a few days ago and surprisingly enough it worked. Crude drawing skills jpg though not big enough to heat much. I was able to feel the heat coming off a couple of hours after the sun went down. I have the material to make this about 4 foot high 4 foot long 4 foot wide.
Assuming the sun hits it 8 hours in a day, how much heat could this put out? Educated guesses would be appreciated as well as factual answers. Before I start on the “real” project I want to know if its feasible.
Enough to warm up a garage, shed, dog house?
We need more information to answer your question.
Latitude affects amount of sun energy you get at a given time of year.
Climate affects how much heat you need your furnace to put out.
Expectations - do you expect it to heat all winter? Up to a certain point in late fall? Supplemental heat to delay a gas furnace kicking in? How warm do you want to keep the building?
I don’t expect it to do much at all, honestly. Maybe warm a two car garage for some of the winter, or even supplement heat in the master bedroom. All of course on sunny days. We live in Pennsylvania, if that helps.
Our solar water heater has done very well, so far, but this project seems IMO like that it would need a lot more sun to work.
As all the material I have where not expensive (As in free minus the lens, the lens where our leftovers from building a solar stove which cooked many a meals this summer, have yet to use it in winter so thats not a known yet.), even a 5$ savings a month would be a net profit after a little use.
We also have 3/ 190watt Sanyo solar panels that we have not installed yet, but electric is not the cost priority right now, heating fuel is.
With-in 5 years I would love to make our home “off grid” but without the tech know how, the heating is rather tough.