The Sun is finite in its energy output - Dyson "Spheres" are a concept for maximising capture of that potentially available energy.

Even the Universe is finite - Olber's paradox demonstrates that the Universe cannot be infinite in both space and time and our current understanding of the Big Bang is that it finite in both, and also in total mass and energy, even if some weird concepts like Dark Energy are growing with time...

But I know what you meant. Compared with the energy requirement for food, water, and air for humans, the Sun is ridiculously large as an energy source. Most of it's energy is "wasted" in making the wind blow, rain fall, rivers flow, birds sing, and the Earth's surface to sustain a substantial excess temperature above the Cosmic Microwave background.

Perhaps you have some ideas to reduce that 'waste"? The greenies might be interested, eh?

8-)