Why are you leaning towards research, what part of energy sector interests you, and can you afford to take the time off from career for a little bit while you change tracks?
For example, I had to work on a voice detection algorithm while working at Wit.ai, and I find it super interesting. I had to explore some research paper to implement and tweak it. I have no idea how interesting it would be to do that full time or part time but I think I would love it. More than working on business product, which I also like.
And what do you mean by "afford to take time off from career" ? Financially speaking?