Exploring solar energy

What to do with all those solar cells

What to do with all those solar cells
DIY solar panel
I decided I was going to make a larger solar panel with the small Solar cells.
I started by making a larger version of Mikes cell spacing template. I improved the design by drilling a hole in the middle of each cell area to allow a finger to poke through to unstick any cells that may adhere to the fixture.
Set up the array with 9 cells in each series string for 45V Open circuit and about 20V under load.
There are 18 strings with a diode on each, to yield about 1.5A.
The cells were laid face down on the fixture, and the wiring was attached. The rear expanded vinyl backing was laid over the cell rear after 4 dabs of silicone was deposited on each cell. When the silicone was set, the complete fixture cell and backing fixture is flipped over to remove the fixture and yield the cell /backing assembly.
A 1/2 " plywood back plate with the cell assembly is placed in the welded aluminum channel frame. The cell face is protected with Polycarbonate clear sheet,
The connections are brought to a plastic electrical box for termination.
Looks professional, and makes a rugged assembly.

Forever solar desk lamp

Forever solar desk lamp
Recycled Insight battery cells
We lost our power a week or so ago, and the usual search for a flashlight with good batteries was a pain in the A**.
In researching the Insight subpacks, I had to remove a weak cell from the stick to examine it. That left 5 pretty good D cells, the only problem being that they are welded together. I carefully used a dremmel grinder to grind off the welds, and in the end had 5 nice high rate NIMH cells. A few short pieces of heat shrink, and they were ready to be put to work. I installed them in a cheap LED emergency lamp, and made a small 4 cell solar charger.The solar panel current was passed through a diode so it would not discharge the cells at night. Now I am ready for the next power outage

Solar headlight

Solar headlight
carbon free light for years
Headlights are a great way to save energy, by taking your light with you rather than turning on room lights. I modified this headlight by punching a small hole in the side, and carefully soldered to the battery end terminals. The wires are run to a two terminal piece of some breakaway .1" on center headers. The solar panels are in series, and a diode is in series on the + lead, to prevent discharge of the cells at night. with 750MHA NIMH AAA batteries, a full day of sun will give several hours of light per evening. The batteries should last for years.

Mikes Saturday Hybrid-Solar- Electric Workshop

Mikes Saturday Hybrid-Solar- Electric Workshop
With the many projects I hope to work on, some extra hands are always welcome.
Check here to see if their will be a workshop if you want to come up and lend a hand.
Present project:
Design, build, and test an IMA-EV mod to give full electric mode to the gen 1 Insight

Read More

C-band dish solar furnace

C-band dish solar furnace
Canning Tomatoes with the sun
Back in the 60's I was given a nice rugged parabolic dish, and had covered it with mirrors. It works pretty well. I have reached aluminum melting temperatures, and run a steam engine.
Old radar dishes are not readily available but old C band dishes are.
Start with an old C-band satellite dish. Cut Bathroom mirror tile into 2" or 3" inch squares.
Glue tiles to dish with silicone rubber,then glue aluminum foil to the back with a thin coating of silicone to seal out moisture, and protect the mirrors back.The small gap between the mirrors will allow eventual total curing of the silicone, but it takes several months for a full cure. The layer of aluminum foil stops the degradation of the mirrors rear surfaces. My dish has been outdoors for over 30 years and the mirrors are still like new.
The horizontal and vertical drives are run by a sun tracking servo amp that keeps it pointed at the sun.
A schematic of the basic tracker is available on the downloads page:Simple Tracker schematic
This generic servo will operate on 12-24VDC, and will run dc motors over the same voltage range. The power transistors need to be mounted on a good heatsink with electrical isolation between the collectors and the heatsink. The servo gain pot will want to be tuned for best accuracy of tracking without oscillation.
The sensing photo detectors are mounted at + and - 45 degrees to form a half bridge.The + of one detector connecting to the - of the other. This "shorted" connection forms a current bridge where the two photo diode currents cancel when evenly illuminated, and change polarity and amplitude of output when unbalanced. The idea is to have the servo always drive the dish to the null point.
I Canned some tomatoes this morning. The 8 quarts of water and tomatoes reached boiling in 6 minutes, but then it was boiling too fast. I had to drape news papers over the mirrors to turn down the heat. I will need to make an adjustable shade for the thing, so I can adjust the boil to a slow steady one. Tracker worked well.I need a steam engine for the thing, and I could make some electricity or pump water.
More information on this project:
Plugging into the sun blog