Solar One of Engineering .com, From the Bottom Up
By Corporal Willy, Sept. 14th, 2009
When there was a lot of interest in this project I wanted to keep going with it, but the harsh realities felt here with the heat in the Mojave Desert during the summer months (Pronounced Mo-ha-vee) forced me to stop the work on one of the most promising solar projects that I have ever come up with to date. Starting too early to beat the heat would also get me lynched by my neighbors and that would really jeopardize Solar One. I think this first picture down below here expresses how bad the heat in the desert was during the summer better than I can describe it to you. This is Las Vegas, Nevada and it is starting to get cooler here now.
Well once again I am moving along on Solar One. I would like to recap what has been accomplished so far to remind everyone and I will keep the reading brief. First of all, generating solar thermal energy is nothing new or mysterious. Rather easy to do, but different ways of holding it for later use with this project seemed to be of some interest to this technical community. Cheap, inexpensive absorbing materials are what my design parameters where meant to accomplish. Let us look at a few of the Thermal Storage Container screen shots I have already shown you before and serve only as a reminder here.
There are two separate copper coils that were placed inside of and away from the 2 inch thick Styrofoam insulation. Then sheet rock of 5/8 inch thick was used to protect the Styrofoam from very high temperatures that could be reached. Remember the article that showed that the Solar Mirror Array was capable of producing temperatures of 350 degrees Fahrenheit? One of the interested readers following this project said that Styrofoam could melt at 200 degrees, so I took this added step with the sheet rock to provide a thermal barrier to protect it. Not shown here in the screen shot down below is the outside ½ plywood box to hold everything together.
This conceptualization screen shot up above is showed again in the actual physical prototype down below. Notice too that I added a vapor barrier of plastic. Even if this melts in place it should be able to help hold the heat from escaping out of any very tiny seams that I endeavored to close up tightly with good measurements, cuts and caulking. Estimated weight so far here is 1200 lbs.
After filling with cheap absorbing gravel materials it will be capped off with another 2 inches of Sheet rock and Styrofoam. I was trying my best to make a thermos bottle type of container so I could preserve the generated heat for the longest periods of time.
After everything was done on this bottom Thermal Storage Container with the copper tubing stubbed out through the sides where it would be picked up later, I covered it over with the orange tarpaulin for protection until I finished building the upper Mechanical Section.
Below here is the actual prototype of the Mechanical Section being build and almost finished.
The upper Mechanical Section will go on top of the Thermal Storage Container and when completely finished it should look like this conceptualization down below here.
Even this screen shot down below does not represent the final design concept, but I think everyone will get the idea of what my intention is here. “The road to hell is paved with good intentions.” The claw that grips the rail will slide when force is applied to the Lazy Suzan in the X axix and that is still to be argued out yet. The holes in the claw arm are for seasonal adjustments with a simple bolt configuration used for the adjustment needed.
The completed 76 Mirror Array that gets mounted on the very top of this Mechanical Assembly is a source of concern now. It weighs in at about 60 lbs so far and it still needs to be mounted to a three foot diameter plywood base. Then all of that gets mounted to the Mechanical Assembly bottom floor area via, a 2 inch PVC pipe with two hole straps, fittings, all hardware and then fixed to a type of lazy Susan turntable for easier spinning on the Y axis. I was going to do some greasing of the bottom of the Lazy Susan Turntable and that was my very first thought but then I realized that in cold climates that would not work too well and in hot dusty areas that would soon turn to mud. So plan “B” is now being considered. Down below is my idea to help in this solution to the problem of what you engineers and designers call the “moment of inertia” to get something moving. Good old fashioned marbles should work to reduce the friction and support the weight evenly. I have to build a corral to keep the large marbles in place. There will also be a center pivot point (not shown) in the Turntable to keep it centered in the bottom of the Upper Mechanical Section Assembly.
Inside of the Mechanical Section Assembly there will be two pumps mounted in that space that will be used for the pumping of the hot fluid from the Hot Box Assembly to the Thermal Storage Container and also for an output draw from container to heat something up. That is something else that is still to be decided upon.
Once this upper Mechanical Section is finished I still have to decide on how I will create a force large enough to turn the Turntable (now on a marble base) and by what means. I still favor the mechanical pendulum clock idea which would also give it the right timing to track the sun with Pendulum adjustments. A correct design and build here is important but if that cannot be worked out, then maybe a pneumatic cylinder might be used along with a tracking device or even a solar powered electric motor with linear actuators. Lots of ways but cheap is my parameter here at all times.
Another problem that will need to be resolved is how am I going to be able to record everything for all the interested engineers worldwide that are following this project? My first and best guess is to use a DAQ recording device hooked up into a laptop near-by. I want to record the data on the heat storage temperatures and also on the outdoor temperatures too. All put on a spread sheet so the engineers can have a ball studying the data that was recorded. So far after a few tries I cannot get any industry manufacturer interested in loaning me one of these units. A donation of even an old working one with the thermocouples would be nice because there are other Solar Projects being talked about beyond this one. I’ve seen some for under 1000 dollars and I offered them all the bragging rights for helping me do this step. With temperatures that could exceed 350 degrees when orientations to near perpendicular to the sun are met with the proper tilting angles, I expect to see some significant data to be recorded. Yes, I’m going to use a pressure relief valve for sure.
Then there is a problem I do not know how to solve at all. I even asked a friend of mine who is a retired Air Force Colonel about this possibility of a problem and his answer was to maintain the strictest mirror focusing on the hot box assembly at all times. The reasoning for this is that we do have a large military installation here by the name of Nellis Air Force Base. The Colonel told me that a simple mirror reflection could be seen for about 12 miles or more depending upon the clearness of the surrounding atmosphere. I do not need any missiles being fired at me, strafing runs or anything else being sent down to eliminate an unknown light source threat coming from the ground, or even a police unit coming here to prevent me from conducting my experiments, shutting me down. I will keep the focus on the targeted hot box assembly by using epoxy to cement all the mirrors into position once they are adjusted properly. Aside of a large military air force base here, we do have many local civilian aircraft, a few traffic helicopters, McCarran Airport for Commercial flights and believe it or not Hot Air Balloons. Yes all of the above including a few birds that keep on eating the fruit off my trees. HHhhmmm, another idea. No I won’t.
Finally there is a problem here in the neighborhood which is really giving me the shivers and shakes. I asked my neighbor for help on this one and so far the only thing that is working now is to collect them instead of throwing them back over the wall. Glass mirrors and Golf Balls don’t mix well. This pee wee sized Tiger Woods will someday be a world golf celebrity I’m sure. Maybe I should just go ask him to sign them for me instead of complaining again. I don’t want to get him into any trouble because his father did tell him in front of me not to hit them over the wall any more. I understand that he is exceptionally good and he recently won the US regional championship for kids in his age bracket. He is eight now.
Everyone is up to date on this project now and when I am not in school teaching or doing other things for the school district, I will be working on this project outside or on the computer doing more designs for it. Bye to everyone for now. Take Care.