Earth has a lot of resources the moon wants and is willing to pay to import. The moon has a shitload of solar energy the earth wants and can be used for scientific endevors.
There are a few problems with lunar power production:
- Not constant: The moon has a day/night cycle. Since night/ day on the moon are rather long, you'd need a large amount of storage if you're going to survive solely on solqr power
-Vulnerable: There are many disasters that could damage your solar power panels, ranging from micrometeroids to solar flares. Because of the lack of an atmosphere/electromagnetic field, these are much more frequent then on earth. Solar flares are exceptionally dangerous, as they can knock your entire system offline for a couple of months. (And no burying wouldn't help, as there isn't much light under the ground)
- Transfer: How are you going to get power back to the earth. Batteries aren't an option. You could try using concentrated microwaves, but microwaving the earth's atmosphere doesn't seem to be a very good idea to me. You could construct a giant laser to laser the power back to earth, but that would only get the power to orbit, rather than all the way down to the ground.
Speaking of giant lasers, you could use these to launch spaceships from earth into orbit. Also, a Moon base isn't going to be profitable until we have properly working He3 fusion(which we don't). Bad news is, we can't properly research He3 fusion until we have acces to it, as the earth's supplies are virtually non existent.
As for solar wind farms, these provide even less energy, and might be better used as a way of slowly getting spaceships to the outer layers. (These do use electricity) Also funny, electromagnetic solar sails can also propulse themselves using planets electromagnetical fields.