The Riverstone Energy Investment Company [http://www.riverstonerel.com/] is listed on the London Stock Exchange.
A £690m investment fund, that is focussed on energy and power-focused private investments. Founded in 2000. Riverstone conducts buyout and growth capital investments in the exploration and production, midstream, oilfield services, power and renewable sectors of the energy industry.

[http://www.shareshop.hsbc.co.uk/shareshop/security.cgi?csi=16480172]

Its top ten holdings make up 59% of the investments

Corp.
Canadian Non-Operated Resources
CanEra III
Castex Energy
Eagle Energy Exploration
Fieldwood Energy
Liberty Resources II
Origo Exploration
Riverstone Credit Opportunities
Rock Oil Holdings
Sierra Oil and Gas