How to add Solar panels to power my small pond pump?

The answer depends somewhat on the size of "small" If your pump needs one amp at 12 volts dc, a 50 watt solar panel, facing East, will start the pump about an hour after sun rise and it will run most of the day. The pump may have short life as it will occasionally get about 14 volts, instead of 12 volts.

If your pump needs one amp at 120 volts ac, you need solar panels (facing South, about 20 degrees above the horizon) totaling about 1000 watts, which charge a 50 kilogram battery, which powers the inverter 24/7. These numbers are location dependent and assumes nothing shades the panels, other than occasional clouds. Your battery may over charge spring and summer, unless you use some of it's charge for other purposes.

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