Sunday, April 20, 2008

Work Plan 2008

Here in southern Canada, near Toronto, the last winter ice has melted and we have been enjoying some very nice sunny days. I have been thinking a great deal about my parabolic solar pool heater project. There are several main items that I want to accomplish this season:

1) Dis-assemble, rebuild and enlarge the solar array with completely new components.
2) Move the motor drive to the other end of the array and install it on a permanent cement post.
3) Stiffen the pendulum drive rod assembly by replacing it with stronger components to accommodate 12 panels.
2) Install new re-designed sensor head mount at the other end (more sunny earlier) of the array.
3) Install a 3 way by-pass valve so that the pool pump can operate while work is done on the array.
4) Install a DC pump and solar panels to enable the system to run without the main pump on.
5) Install a UV-C water sterilizer unit powered from the solar panels.

Last year I spent about a month making new ribs and hangers carefully finished with epoxy primer and urethane topcoat. The new set of about 100 ribs and hangers (enough for 12 reflectors) is ready for assembly.

I would like to try Lexan flexible mirror and I did find a supplier. Lexan should be more durable than Acrylic. Likely I will end up with an assortment of reflective materials on this year's array, allowing comparison between them. I'd also like to check current pricing of the main materials.

I am going to tip the array up a bit more to better match the sun's orientation in this climate. Although the array can even be flat to the horizon with some loss of efficiency, the performance with improve the closer that the plane of the array is matched to the sun's azumuth at your location. Here is about 42N. I won't go that far, but currently they are only at about 20 degrees or so. I may push them up to 30.

Thank you for your interest in this project. I am logging your emails received and I hope to announce the availability of a set of plans by the fall. Please check in here to see how I am doing.