I bought a low voltage DC pump and a solar panel, about 3ft by 1ft, and
unless it was pointing directly at the sun it did mostly nothing at all.
However, when the sun did shine, the solar panel powered my pump too much:
water was spewing out of my water feature too fast. So you need a battery
if you go down this route.

With the solar panel in a position of dappled shade (still a lot of
sunlight getting to the panel) the pump would stop. If the solar panel was
directed away from the sun (by not very much IIRC) the pump would stop.
The company I bought the solar panel from said it would work in overcast
conditions!! I got my money back.

My water feature is now powered from the mains, and works just right.

Regards,

Paul.

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