Rani asked if cooking in a solar oven takes longer. The short answer is yes. The longer answer is "it depends". Generally, the oven I have (the Global Sun Oven)will not get hotter than about 350F and ours tends to hang out at about 250F (which is sufficient to cook meats and brownies). I'm thinking that if we would get it out during the hottest part of the day it would easily hit the 350F threshhold.
Mr. Gaia cooked the corn and salmon in 2 separate batches (it would have been big enough for both, but I don't think he thought of it) and it took about 2 hours long. So, probably he could have cooked both in about 1 hour.
The way the oven is made holds in the moisture (like a baking bag) and so even as food cooks for long periods of time, it doesn't dry out. We've had sausage and salmon cooked in it and they were both very tender and moist.
Wednesday is supposed to be sunny and hot (hitting 100F) so I'm going to mix up a batch of bread dough tomorrow night which Mr. Gaia will put out to bake at noon. That will mean it will cook for 4-5 hours, but the cookbooks we've looked at say that in the sun oven, this will be okay.
I'll report more after I've tried it. So far, our experiments have been successful - we've done roasted corn, sausage, salmon, roasted almonds and brownies.