One night I stumbled on the subject of solar collectors. The guy was using several mirrors to bounce sun light to a single spot. The result was obviously the combined power if all the mirrors. He was aiming it at a solar panel and was able to increase the output fairly significantly. I started looking around for anyone who had done similar experiments. I found so many cool tributary ideas. The range included “death rays”, cookers, ovens, air heaters, water heaters, stirling power.
I have always been interested in solar, but my scope was limited to electrical panels. I have been in the process of bulding my own solar panel, but it has been slow going, and met with a few setbacks. I suppose in hind sight that it makes sense, but there is so many uses for solar energy. The more I learn, the more I am shocked that solar is not playing more of an important role in this energy crisis we find ourselves in. 
One of the things I was really intrigued by were solar collectors. Using a parabolic reflective surface to focus the light to a single point for maximum power. I like the dish idea because it is a fairly controlled experiment surface. Using a set of mirrors presents a danger of shooting somewhere untended… catching something on fire.
I work at a TV station and there is a small yard full of “obsolete” satellite dishes. I talked to our engineer and he said I could take one. I took one of the smaller ones, a 1.8 meter dish. Once I got it home I cleaned it as it was covered in years of crud. I took the feedhorn off as it was not necessary. I got a roll of heavy duty aluminum foil and some spray adhesive. I covered the inside of the dish with the foil shiny side out. It became immediately obvious that the reflection idea was working. In just garage light, the focus spot was very bright. I used a piece of PVC pipe in the feedhorn holder hole to hold my test subjects I covered the holder with foil to keep it from melting.
I started with a piece of paper as I figured that it would be an easy thing to get lit. I wadded it up and stuck it in the end of the PCV tube. I pulled the dish outside and aimed it at the sun. I kept a wrench in my pocket at I was constantly having to adjust the angle of the dish. I got it aimed and angled and was very excited. I waited…and waited… but nothing was happening. I was scratching my head. This thing should have been lit already. I put my hand near the holder and could feel heat. Then the reality smacked me. Duh! White paper is highly reflective. I replaced the paper with a piece of cardboard. As soon as I got it set it started smoking. It smoked more and more and finally ignited. Muahhh ahhh ahhh ahhhhhh!!! I have the power… Yes, you bet I was excited.
My neighbor came over to see what I was doing. He was concerned that it would hit his house and catch it on fire. I assured him that, no, it was focused to a point that was sort of restricted by the shape of the dish. I am not sure that he believed me.
My next experiment… water. I grabbed a coat hanger and fashioned a holder. I got a water bottle from the recycle bin. Having learned from the paper, I spray painted the bottom of the bottle black. I filled the bottle about a third of the way up with water I shoved the hanger bottle holder into the PVC tube and watched. Rather quickly I started to see condensation inside the bottle. I figured the bottle would be a safe thing based on the concept where one can boil water in a leaf. It did start to melt above the water line so I covered the top with foil. Within minutes the water started to bubble, and soon after it was at a fairly strong boil.
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