From this article: http://www.apple.com/environment/renewable-energy/

"By the end of 2012, we’ll meet the energy needs of our Maiden, North Carolina, data center using entirely renewable sources. To achieve this, we’re building our own facilities that will provide over 60 percent of the clean power we need."

Solar is usually a good investment, especially when you can start selling your excess back into the powergrid for a slight profit. One of the current barriers to solar is the cost -- I think Apple have more in the bank any other company right now.

As for "why there", maybe that was one of the sunniest parts of the US. Maybe Apple has a datacenter nearby or will soon build one -- either for expansion of current cloud services or for new services.

Well I assume it's for the datacenter? Since it's right next to it...

Because they have to have solar to make the majority of their customers feel that they are green, and the governor has continued to let large corporations make the NC taxpayers bear the burden to the corporations benefit.

Have you ever grown an Apple without sunlight?