During a year when deals commonly fell through, and fundraising efforts were often suspended, First Reserve stood out in multiple arenas. The Greenwich, Conn. private equity firm, which focuses on the energy sector, raised a $1.2 billion infrastructure fund, launched a Hong Kong office, participated in one of the year's largest exits, closed nine platform acquisitions and completed 30 add-on acquisitions.

First Reserve typically writes an equity check for $500 million and partners with other investors to achieve growth, or when there is an alignment of interest. In the case of the Cido deal, the firm co-led a syndication of PE investors that included WL Ross & Co., China Investment Corp., Fairfax Financial Holdings Ltd., Morgan Creek Capital Management and PPM America Capital Partners.

In another deal, First Reserve partnered with Finmeccanica to acquire a 45 percent stake in Italian power plant producer Ansaldo Energia. The total transaction value was $1.6 billion. The firm also completed consortium deals with the likes of Energy Corp. of America and the California Public Employees' Retirement System, or CalPERS.

Among other deals was backing Amromco Energy. The Amromco investment is the first stage in First Reserve's plans to build an oil and gas platform in the Central and Eastern European region. The firm also formed Renovalia Reserve, and committed $150 million to acquire wind companies.

Equally prolific on the sell side, First Reserve sold energy infrastructure company Dresser to General Electric for $3 billion, in one of the largest private equity-backed exits of the year. More than 85 percent of Dresser's revenues are derived from energy customers on a global basis, which was appealing to GE, sources say.

"While capital markets have opened and closed, strategic acquirers, who have built up cash balances in recent years, have continued to aggressively pursue energy businesses with strong revenue growth and earnings profiles," says Mark McComiskey, managing director and co-head of buyout funds for First Reserve. The firm was also able to complete a successful fund raise-a great feat considering that many private equity firms have had to suspend fundraising efforts due to lackluster interest from limited partners. First Reserve closed its Energy Infrastructure fund oversubscribed with $1.2 billion.

The fund's infrastructure investments are focused on various energy verticals including pipelines, liquid natural gas facilities, renewable and conventional generation, and regulated distribution, including electric and gas utilities. Geographically, the fund concentrates on North America and Western Europe. Its first investment is a joint venture with SunEdison LLC called SunEdison Reserve, which was formed to own utility-scale photovoltaic power-generation facilities. Capping its accomplishments, First Reserve opened a Hong Kong office to take advantage of the rapid growth rate of energy consumption in Asia.