We rejoice every day the sun comes out and we turn off the furnace or stop feeding the wood-fired heater. Here is a complete procedure for building your own space heater that only requires the sun to work. We have used this method for over twenty years and I finally got around to a book so others could do it, too. A passive collector works by having the sun heat air which then rises by convection and passes back into the house, thus causing more air to be drawn out of the house into the collector and the process repeats itself, automatically stopping when there is no sun and starting again the next sunny day. Even a cloudy day does not totally stop the sun's rays and the collector continues to work.
The key to collector success is an efficient heat exchanger; in this case it's tin cans. That's right: As in soup or beans or even pet food cans. Properly assembled, they transfer sun heat to house air. The book describes How To Do It.
The nice thing about a passive collector is that it doesn't cost anything to run. No moving parts, fans, motors, etc. It just hangs there and works, day in, day out. Not only is the heat from the passive collector free, but it requires almost no effort to acquire it. It's Free Heat.
Say, did you get the idea that I'm trying to sell this idea? You Bet! This is the neatest thing since sliced bread and once you finish it, it just keeps on working. I like that and I want everybody to have one.
