This bit of information may be of practical use to some of my readers who like to think outside the box, so here goes: a Hare Krishna sister recently sent me an interesting video of devotees cooking with a sun cooker: a solar powered stove that can be used outdoors on sunny days to reduce dependency on conventional electricity. It uses free energy, generates no pollution, needs no wood, produces no smoke, and helps save the Earth. It may even add more vitamin D to our meals, since it derives its heat from the sun directly.
Sun cookers have been prominent in the relief efforts in Darfur, and efforts are being made to take solar ovens to impoverished parts of the world. Already, an entire village in India uses solar ovens, and there's even a video on youtube showing a home made solar oven that works in slighly higher than freezing temperatures.