Renewable energy has got buzz, growth and growing government support. But it's no secret that it still makes up a small portion of the overall energy mix. As interest in renewables increases, the question has begun coming up more and more often: When will renewable energy companies catch up to conventional energy companies? That is, when will we see an Exxon Mobil Corp., Chevron Corp. or ConocoPhilips of renewables?

In other words, the next BP of renewables could be BP.