My stupid science project:
Sometimes I can be a doggone good engineer but I don't build well. Therefore, half of my projects end up as scattered notes in a drawer or very cool diagrams somewhere else.
I've been studying radioisotope thermal generators (RTGs) for some time and think I've come up with a half-decent design for a heliothermal generator using focal mirrors and off-the-shelf thermocouples. Essentially, think a heat collector with thermocouples back-ended into a cool granite block for maximum temperature gradient.
My generator would look like a very shiny satellite dish about 18-20" in diameter focusing solar heat on a "hockey puck" containing the ends of about 50 thermocouples. The others ends are sheilded and pass into a granite block or other thermal-negative material to maximize electrical potential.
The math indicates I might produce about 380 Watts at 1vA under optimal conditions. Cool, huh?
I see more notes in more drawers in my future :-)