Effectiveness of a Motorized Tracking Solar Panel

[dvscrobe]

My daughter is entering her third science fair project on solar panels. The first, she determined that there was an ideal tilt angle of a solar panel, facing True South on a particular clear day, that provided optimum electrical output, as compared to other tilt angles. The second, she determined that a tracking solar panel (adjusted manually by hand) provided optimum electrical output, as compared to a static panel that had zero degrees tilt and was facing True South. For her third project for 9th grade, she is currently challenged to construct a tracking solar panel that is auto-operated by motor action. This way, the project can be self-run while she is at school. Multiple whole days, regardless of cloudy or clear weather could be studied. My daughter has not learned how motors work yet. It has been a successfull struggle for me, getting her to finally understand AC and DC concepts. And, no, the concepts don't include the band. Haha. Whatever is constructed though has to be something very, very simple. I do know that two axles, each driven by a motor, are a must. The actual design and the programming of the motors is gonna be tough. I have learned that in 9th grade, the beginning of high school, computer programming is a requirement. So maybe the programming knowledge can be tied into this idea somehow.

[matthewgettemy]

I don't know much about construction of motorized systems, but I'm pretty sure that it will be difficult to construct from scratch.
An idea came to mind that you might want to try, if you are just interested in the actual output of the panel, and not so much interested in the development of the tracking system. You might want to try and find a telescope that automatically tracks stars and mount the panel to the end of the scope. Then set the scope to track the sun (don't look through the scope when it's pointed at the sun!). A lot of people give up on telescopes shortly after buying them so you may be able to find a cheap used one.
How long the batteries would last if you have the scope on all day is another question.

matthew

[rmarz]

dvscrobe - I did a simple search on 'simple solar trackers' for solar cell panels. There are many demos shown on YouTube that are pretty innovative. Several use Arduino controller based solutions, but I wouldn't suggest that unless you are willing to really study some of these robotic controller systems, it might prove to be too much bother. Another I thought was really interesting used a Radio Control servo that connected photo-resistors into the potentiometer feedback circuit. These are fairly low cost and available at a hobby store that feature Radio Controlled models. Most of these videos seem to be single axis control, but no reason that you couldn't use these solutions to create 2 axis control. Here is a link to this RC servo system. You might decide that single axis azimuth control is sufficient, and a reasonable compromise to the added complexity of providing the additional, marginal benefit, of elevation control.

http://www.youtube.com/watch?v=Rt4HZOsO ... A&index=13

Rick Marz

[BillBushnell]

Hi dvscrobe,

If you want to keep it really simple, I suggest you just use a high torque clock motor.

http://www.etsy.com/listing/93375222/rh ... Mgod_D8AMQ

You need to attach an arm to the clock shaft and then create the equivalent of a "walking beam engine" linkage that changes the circular motion of the clock to a side to side motion. See the image below but picture it laying on it's side

http://image.made-in-china.com/2f0j00WB ... 21502-.jpg

The linkage can be made out of simple pieces of wood or stips of metal you can purchase at a hardware store By adjusting the length of the arms you can get the hour hand of the clock to drive angle of the solar cell.

Best of luck,

[dvscrobe]

Thank you all for your replies. They are very good ideas. I have a year to guide my daughter to a final design. I talked to her about how electric can be used to make a motor turn and how the turning of a motor can be used to generate electric. She seemed receptive to the concept. So I am leaning on teaching her how to use a servo motor, which the local hobby store has. Will follow up on this forum thread later.