(a) energy emanating from the sun in the form of heat, light, etc.; (now chiefly) power generated by harnessing this energy, solar power; (b) the…

energy emanating from the sun in the form of heat, light, etc.; (also) a mechanical force or other influence ascribed to the sun.

power derived more or less directly from solar radiation.

The flux of radiant energy per unit area, esp. an area normal to the direction of travel through a medium.

U.S. Solar radiation as a source of domestic or industrial energy.