Make your own solar thermal panel for about $50 – “One of the main uses of energy in the American home is to heat up water. It takes a lot of electricity to heat up water, this cost a lot of money. All day while you are at work, or at school, the sun is busy heating up things outside. If you are a little kid and you get to play outside all day then you know all about this. Lucky for us the sun is free, all we need to do is figure out a way to use that energy to heat water. That’s why we are going to build a solar thermal panel, these guys are great at heating up water.” [via] – Link.