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Solar power controlled pump photo cell shutoff? Answered

I have a water feature in my front yard (small reservoir, and old style pitcher pump) that I ran on battery/solar power last summer. I would like to have the pump shut down during night time, but run during certain periods of the day. and charge a 12VDC battery via solar panels. I had it working last summer, with a small solar fountain pump, but it would run the battery down by continuing to operate after dark. There is no need for it to operate at night. I need a way to use a photo cell that would activate with daylight then de-activate at dark.


Here's a very simple idea you can get the bits from a Radio Shack, if they're still open...

It uses the solar panel voltage itself to turn on the load. You can mess around with a pot to get it to trigger where you want. When you use a transistor like this, make SURE you put the diode in the circuit like I've shown.


Thank you so much! It's been a busy year but I haven't forgotten the project; just haven't had the time. (think replacing sewer lines in 2 houses, and a bout with abdominal cancer)

Do a search for an LDR light sensing circuit.