The long overdue, final instalment, Part #6 of our solar air heater.
This was a tremendously rewarding project.
I learned a lot between the time I started this project and the time I finished it.
The solar air heater I ended with is different than my original plans. As I learned, I altered the design. The size of the heater changed to maximise the use of available materials. I dropped the idea of using a solar-powered panel to power the fan. If I was off the grid, I would have gone that route, but with AC available, the small power consumption of the fan would never justify the cost of a solar power panel. I learned about the different properties of high heat paint, and what brands work on Styrofoam insulation. I learned about the balance between air flow restriction and temperature delta. I ended up changing the design of the heat chamber to reduce restriction and increase CFM. My first unit completed in 2017 produced too much heat and not enough air flow.
It is interesting to re-watch the first video in my series on this topic. Three years ago I stated that “at 12 noon on a sunny winter day at 45 degrees north, my design should produce between 4,600 – 5,000 BTU, somewhere between 1,350 and 1460 watts. I’m pleased to say the final unit is producing that and more.