Saw this man's column in today's paper. You can read about it and many others at his website: dulley.com Plan number 442 discusses how to build this solar window heater and how to use it to cool a home as well. He also has an virtual house tour of his energy efficient home as well.
I have seen several designs for solar window heaters. As long as you have windows facing east/south this should be a good way to supplement the heat in your home. They are easy to construct although I think they look alittle obtrusive. I have not built any yet but they do look interesting.
My brothers have been doing this for years with their EAST facing windows. Using a 3/4 sheet of styrofoam painted flat black, and fitted to the window, they cut several round holes in the bottom & top of the sheet. On the bottom holes, they taped squares of toilet paper over the holes on the black side (just the top edge, so it hangs like a flapper valve). It makes the room rather dark, but it does heat up the room rather nicely. They just pull them down after chores in the morning. It also keeps the room warmer in the night. Do not block the holes though, the one time it was done, the glass thermal pane window got so hot it cracked. There WAS a solar panel manufacturer that produced a 2x2 stackable (air) collector that went on the side of houses back in the Jimmy Carter era. My wife's folks had one - it still works very nicely in Wisconsin!
I'll be honest - maybe I'm just a bit slow tonight but his description made absolutely no sense to me. For example: "It is basically a flat box with two shallow chambers inside, one above the other. The chambers are connected at the outdoor end." Huh??!?! Can anyone explain this in plain English??
The box is on the outside of the house with a part of it extending through a window. The box generally extends from the window to the ground. The window is usually one that slides up/down instead of left right. As the sun shines on the box the air inside of the box is heated and convection air currents carry the warmed air up through the box until it reaches the top which extends through the windows. The chambers inside the box causes the air to weave side to side as it moves through the box. As it weaves through the box the air is heated. This weaving also slows the air down a bit which allows it to be warmed better than just allowing it to flow straight upwards..
