10kW Dish System for Home Use

     This project was started as a Lark prior to beginning college at Mt. Sac in Walnut California in the summer of 2001. After the energy crises and the Enron failure, my interest reemerged into pursuing affordable solar power generation. A friend of mine that I did some computer work for had an old eight foot aluminum satellite dish, and when I asked him how much he wanted for it... he said just take it home and that he was glad to be rid of it. So I  found a shovel and started digging the thing out of the sand and finally hauled it home strapped to the top of my car with the concrete still attached to mounting post.

    The first thing of course that needed to be done was to sand the brown paint off of the front and polish it. This did not turn out to be a simple chore. After completely destroying three auto polishers retrofitted with sandpaper and polishing compound and also an industrial strength Milwaukee grinder, I gave up and decided that I would have to build my own polisher like  the type the use to polish the mirrors at the Mt. Palomar Observatory. This necessitated that I take some machining classes at Mt. Sac., and while I was doing that I thought that it might be a good idea to take some math and science courses.

    One year later I finally got around to building the polisher that I needed and was nearly finished with only about 10 more hours left to work on it, before the summer break and admission to Cal Poly.  I was not able to gain access to the machine room until the winter quarter, and it was near the end of the quarter when I finally finished the polisher.

    It is now sitting proudly on the workbench in the garage waiting to be applied to the dish. However I have come to the conclusion that if I am going to be real about building solar power stations... I am not going to be retrofitting old satellite antennas. I need to build the reflector dishes from the ground up, and Prof. Ravi in the materials department has promised to assist.

    It turns out that an eight foot dish will only collect about 5kW of sunlight power, and  at a maximum thermal efficiency of about 40% I would only realize about a kW of useable power.

    So the 10kW dish will need to be bigger that 8 feet in diameter anyway, so while the old satellite dish was fun when I didn't know any better, now that I am in engineering school it can wait until I have completed a proper design evaluation.

    As you may or may not know... the mirror surface is critical to the operating efficiency. The satellite dish was in fact polished to a near gloss where I could just barely make out my face in the reflection. The problem was when I took it out into the hot summer sun and aimed it at a piece of wood and then some paper... the paper and wood never even got barely warm. That was pretty disappointing. It just goes to show how much sunlight is reflected away from the focus when there are tiny imperfections on the mirror surface, and how important the finish is going to be.

    Stay tuned for further details as I have moved on to a bigger and better system for the time being.