Private equity firm Riverstone Holdings has invested more than $6 billion in the energy and power space. According to the website: "The current transformation of the energy and power industry is creating market inefficiencies and dislocations that require significant capital investment and exceptional management teams. Riverstone is a catalyst, playing an active and opportunistic role in the ongoing restructuring of the energy and power industry."

Well, this week, the firm got a new team member – Lord John Browne. He certainly understands the energy market; that is, he was the former CEO of BP (NYSE: BP).

Now, he will be a managing director of Riverstone.

Interestingly enough, he was serving as an advisor and chairman to private equity firm Apax Partners, which is a more general purpose fund. But, he has resigned from that post. He is also no longer on the board of Goldman Sachs (NYSE: GS).

So, I guess Lord Browne will have lots of time to devote to his new gig. And, in light of his extensive background in the energy business, it does look like a big win for Riverstone.

Tom Taulli is the author of various books, including the Complete M&A Handbook and the EDGAR-Online Guide to Decoding Financial Statements.