It seems like solar panels work best when in sunlight, and infrared radiators work best when shaded. If you have a square 1 m^2 solar panel, and a square 1 m^2

It seems like solar panels work best when in sunlight, and infrared radiators work best when shaded. If you have a square 1 m^2 solar panel, and a square 1 m^2 area to put it in, and you live at 35 degrees north latitude, you angle your panel up 35 degrees facing south. That gives you .428 m^2 of area, angled at 55 degrees, facing north, which will always be in the shadow of the panel. So stick a rectangular infrared radiator behind the solar panel. So the area needed would be less than that needed to replace all of humanity's energy use with solar power, but the exact amount less depends on the latitude at which you place the solar panels.