Say solar panels converted 100% of energy from the sun. How much energy would a solar panel get that was, say, 1 square foot? What I mean is how much of the sun’s energy actually gets to the solar panel?

(may be broke/outdated!)
Say solar panels converted 100% of energy from the sun. How much energy would a solar panel get that was, say, 1 square foot? What I mean is how much of the sun’s energy actually gets to the solar panel?