As a kid, I had similar project known as "solar cooker" at the time. I had found blueprint for the device in the "Galaksija" magazine, which was very popular science magazine in former Yugoslavia. But my device was quite simpler and less powerful, but it could boil 2l of water in about 10min. if it is properly adjusted on bright summer day. :)

Unbelievable! How poor and fascist arguments... "Linux... is at the end of its life cycle" - no comment...