The moon is much, much closer than 8 light minutes away. Are you thinking of the sun? It's already doing a good job at sending energy to us from nuclear reactions.
That’s the joke. The Sun is safe, cheap fusion at a distance. Enough sunlight hits the Earth in 30 minutes (I’ve seen figures as low as 2 minutes from the UAE, but am conservative for argument’s sake) to power humanity for a year.
Significant compared to the Earth’s surface area and the amount of radiation we receive. Sure, we get a lot of energy from the sun. But no, we’re never going to turn more than a tiny fraction of that into electricity. The orders of magnitude just don’t match.
Ok, but we don't need that much energy. Something close to 200 petawatts continuously strike the surface. Humanity uses something like 15 terawatts. To fully cover our energy needs we'd need to capture less than 1 in 10,000 watts or 0.01% of the sun's energy hitting earth. But I don't think 100% solar is anyone's goal. So we'd need to capture less than that.
So it seems to me that we could absolutely cover a significant amount of our energy use.