Solar Cooking - guest post

Thanks to my husband for sharing his latest alternative energy experiment!

For some time now I have been interested in solar cooking and alternative energy of all sorts. I knew it was probably very simple and inexpensive but I just never got around to trying it for myself. On Tuesday, I got the idea that it would be very fun to try solar cooking on Earth Day and looked at the calendar and discovered that Earth Day was the next day! After downloading and printing out a free book here, (58 page PDF), I got a piece of cardboard from work and headed home.

Of course Gina is always game to try something new and she said " If you make a solar oven for earth day, you need to write a guest post on my blog about it!" I went ahead with my experiment and now am paying the price for it! If you want to stop reading now, I really don't blame you!

After putting the children to bed, (Note this important step!) I laid out the cardboard and marked out the measurements from the manual that I downloaded. I know several people that have made the box cooker type, but wanting to be different and able to easily transport mine, I made the "Cookit" style which is basically just an angled reflector.

We cut out the cardboard and glued tin foil to the one side and left to dry overnight. The next day (Earth Day) was forecasted to be rainy all day. Not a good cooking day with this method! But Thursday looked promising, so I had an extra day to pull it all together. I took two foil 9 x 13 pans and spray painted them a flat black and also picked up some turkey sized oven bags.Thursday morning, Gina mixed up a batch of brownies and put it in the one foil pan. The other pan we turned upside down on top and fastened them together with paper binder clips. We put our oven thermometer into the pan as well and all this all went into the oven bag and was sealed up.

Since I normally have to work during daylight hours, I took it with me, knowing that even if it was a totally flop, I would have plenty of help to eat raw brownie batter!
I set up the cooker toward the morning sun and set the thermometer where I could watch it out the window. The day turned out to be partly cloudy, at least for the first few hours. Finally around 11:00 it was pretty much full sun and the pans had heated up to around 200 degrees.

At 11:30 my lovely family stopped in to see me and I was anxious to see how the brownies were doing anyway, so we opened them up. They were just starting to set up around the edge. Of course the children wanted to stay until they were done, but I had figured out by this time that it would be several more hours. We set the pan back in the cooker and it took nearly 45 minutes to come back up to 200. Solar cooking takes patience! Already co-workers were wondering if we couldn't finish them in the microwave! Americans!
Finally around 2:30 we took them out of the cooker and the pan was empty soon afterwards!
I learned several things from this experiment:
- This style of cooker probably needs more direct sunlight then we had that day. As soon as the sun would go behind a cloud the temperature would drop in the pan 10-20 degrees.
- Not much cooking happens below 200 degrees. At least it is a slow process!
- Solar cooking doesn't need much looking after. One of my other many hobbies is cooking in a cast iron dutch oven. These need almost constant attention as coals need started then arranged on the pot, then the pot need turned so that there are not burnt places. Dutch oven cooking is very fast compared to solar, but requires more work.
-11:00-3:00 is probably prime cooking time which makes it hard to have brownies for lunch especially since I like to eat at 11:00!

I'd love to hear if any of you have experimented with solar cooking!