Very Passive Solar Heating

It has been TOO long since I've paid attention to this blog! Many reasons, most of which involve taking care of my parents - so please forgive me.

However, that's not the topic of this post. I found a very cool site during the last year and will highlight it in a future post. Right now, I'm going to focus on the topic of passive solar heating.

We all know that if you sit in the sun, you'll get hot. If you sit on black top in the sun, you'll get burned.

Somewhere in between those two things is what I'm trying to work with.

Looking at other solar heater designs, I thought of an idea. Since so many use windows, and windows that are fastened to the wall of your house, why not use the windows that are incorporated into the wall of the house - namely, those you peer out of on a daily basis.

I have the perfect room for the initial experiment - it's a very small, unheated room. 8x12 with 2 large windows that are about 20% of the floor space and face ESE and S (roughly). They have full screens that sit on the inside of the frame. I took those screens and set them at an angle - not the perfect angle for my lattitude, but close enough without making fancy frames to hold them in place - right now it's the curtain rods doing the work.

On sunny days, this simple arrangement heated this room 5 degrees when the temperature outside was between 25* and 32*. Cloudy days had absolutely no change in temperature and colder days saw less temperature change.

This year, I bought good old black netting - similar to fish-net stockings, but smaller grid. I used double faced tape, cut the netting to size and fastened it to the window frames. Very close to the window on the bottom, as far out on the top as possible without making a special frame. I discovered you need 2 layers of tape since there is so little surface area holding the netting to the tape - sandwich the netting between the layers of tape. Works like a charm.

While there isn't as much surface area to the netting as with the window screens, it is far darker than the screen, and will allow for more air flow, which should create more or = heat exchange as the screens.

I've set them up in the dining room windows, of which there are 4 and in 1 living room window - using the last of the netting I purchased.

I will be keeping some unofficial statistics and will post them in a month or so. It's a $2 trial. That works for me. And if I got 5* for that $2 investment, that should add up to a 5-10% savings on heat - paying for the netting in roughly a week. I know - not every day will be sunny, most of all where I live. However, even if it turns into a mere 1% savings over the heating season, it'll still be at least a 1000% return on my money. I'll be having it!