My experiments with solar energy go back to my TV repairman days at Color TV & Stereo Clinic. I built an exhibit for an energy fair at MIT in the 70's, where I built a sun tracking fresnel lens concentrating solar collector that ran a toy steam engine in February with the energy in one square foot of sunlight. I also made, with the expenditure of lots of labor and beer, the 7 foot solar furnace that can melt aluminum. that is explained in the plugging into the sun page. My home heating system is comprised of an air to air heat pump with an electric furnace back up. The system was designed with eventual solar input in mind, so I have both air to water and water to freon heat exchangers. I invested in two solar hot water collectors made by the Apricus company in Taiwan. The evacuated tubes look to me like the best way to harvest the suns rays for water heating in harsh New England winter conditions. I have a modified coal and wood stove that work alone or in parallel with the solar to store heat and heat my domestic hot water. My coal supply is a large cut off benzine tank with a slide back roof for loading. The coal is dispensed into 5 gal pails, via a surplus modified treadmill, that is driven through an old lawnmower transmission by my rechargeable drill. |
Control software
Better photos of the heating schematic: heating schematic and the labview control software: Labview control software |
Storage and control
The mixing of flows and control of the three heating loops is with a custom Labview program and servo controlled valves.The hot water tank is keep at the storage tank temperature with an attached tube in tube heat exchanger. |
The Coal stove
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The evacuated solar tubes
I was impressed with how well it works. My 24" parabolic coffie pot will boil the water in less than 1/2 hour. I built a stainless steel tubular frame for the tubes so the angle could be adjusted for different times of year. |
The wood stove
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