Solar Cell Circuits
Solar Powered Tool Shed LED Light -- July 14, 2017
designed by David A. Johnson, P.E.
I have a lean-to 8ft by 12ft shed next to my house. It is full of lawn chemicals and garden supplies. There were times when I needed to get something from inside the shed during the dead of night. Early on I had to use a flashlight. But later, I installed a series of five 12v LED light strips on the ceiling. Each strip contained 15 3v white LEDs. The strip had 5 strings of three LEDs, wired in series, with a 150 ohm current limiting resistor. Each 12 inch strip drew about 100ma or about 1.2 watts per strip. Up to 6 strips can be powered by the drive circuit shown below for about 4 hours of illumination. A single push-on/push-off switch turns on and off the lights.