That's right! Because we have plenty of rocks right here on earth! Now, work out the economics of using Earth rocks to build power satellites. Compare that to

That's right! Because we have plenty of rocks right here on earth! Now, work out the economics of using Earth rocks to build power satellites. Compare that to the economics of using material from the Moon. The difference is orders of magnitude. Will that take a lot of energy? Yes, but there too, the difference is orders of magnitude.