luckyfish
My guess it's pretty hard to deploy new technologies inside of powerplants. It takes years of testing, larger sums of money, and very long sales cycles.
So it makes more sense to develop a grid-less version for the developing world, that would serve both as a commercial product and as a proof of concept for the technology, and would take much less time and money to deploy.
You can build some serious prototype of your idea using a site prototyping tool like axure. test it with users and refine. it's not exactly a minimum viable product , but it's close.
Also do market research , and some general business plan.
It would be a lot easier to convince a hacker(or maybe even an angel) to work with you on your project after you finish those two things. And those 2 artifacts would take your project a step further.
Zynga/farmville is a great example of such process.
I'm not sure that one application will replace facebook, probably few/many games and virtual worlds.
[1] http://www.dvorak.org/blog/2010/06/24/so-you-want-to-develop...