Are you going to move to the country where you start this new company?
Also, if it is going to be solar/wind powered, doesn't that greatly limit the locations where you can do it?

Also, I don't know a lot about mining, but I would guess if you buy something like http://www.solarminer.com or build your own mining equipment powered by alternative energy, it won't be as cutting edge as what is needed to make a profit with mining.  Also, keep in mind that in a hot climate the cooling costs for the computers might offset the low cost of the solar power.

Using the solar/wind electricity for mining may pay better than selling the electricity, but overall you would really be taking a big risk setting up an alternative energy operation in a country you know nothing about.

- Eric