A little over two years ago, I wrote "How to build a Tracking Parabolic Solar Collector" describing my self designed and built working prototype and test results. I have tried to show what a determined person can do with pretty ordinary tools and materials - a high performance Do It Yourself (DIY) solar heater.
Since then, I have had lots of feedback from the 600+ people who bought the book and Thank You for that!
I have been thinking about improvements. Last year, I did a series of measurements and started working with glass evacuated tubes as insulators for the solar collector to enable higher temperatures and winter use.
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Current 2.0 design goals:
Simpler hand or machine made ribs Previously, there were three different types of ribs - now one rib does all three jobs. The new rib is simpler and lighter. Twelve can be made from a 2x4' (30x60 cm) sheet of material, only seven of the original could be made from a sheet this size. The ends of the rib are simplified to suit angle profile side channels which should be available anywhere.
I am making small quantities by hand using patterns while I work out the design. Simultaneously, I am creating .dwg files for each part for CNC laser or water cutting.
This new design will be described in detail in an upcoming book.
(click any pic to enlarge)
Simpler side channels Now I am using a standard angle profile with a very strong and precise joint that can be made by hand or machine. Many different types of material can be used, whatever is locally available. It only needs to be straight and suit the local climate. The resulting assembly is robust yet light weight and completely grips the reflective sheet along the long edge and supports it accurately from below.
Better balance, more efficient Each collector assembly is balanced before installation. Balance ensures that each takes minimal force and energy to position from the drive. In this way, different material can be used and the assembly adjusted just once for any resulting balance shift. I think I should be able to swing up to 25 reflectors (13 now) with the existing motor drive with this new method.
Insulated, high temperature collector option I will show how to suspend a standard glass evacuated tube at the focus and use it as a large thermos bottle to surround the collector. Higher temperatures and or winter use are thus made possible with this design.
A ball bearing support and a much stiffer reflector frame will make high altitude use possible (near vertical mounting). You can use this either insulated or not.
Flexible size I will show you how to make several different sizes of collector. All are based on the same parts.
You can make this in your garage (or where ever you make stuff.) You need some basic woodworking tools. I have improved some of the methods. It will take less time to make.
Thanks as always for your feedback.
Please show your support by buying my book. My work is supported by book sales. Perhaps you've noticed that I haven't monetized these pages (no ads)? Besides, my current book makes for good background reading on this project. Much of Gen 2.0 (the motor drive and the sensor) are the same as the book.
The parabolic reflector can also be used as a light source.