On net, we are radiating about as much energy into space as we are getting from the sun. (Even the worst scenarios of global warming are rounding errors compar

On net, we are radiating about as much energy into space as we are getting from the sun. (Even the worst scenarios of global warming are rounding errors compared to the energy of the sun that hits the earth every day.) In any case, 'closed system' specifically refers to matter. Energy is allowed in or out. Compare https://en.wikipedia.org/wiki/Isolated_system https://en.wikipedia.org/wiki/Isolated_system and see the little graphic on the top right.