The latest news concerns private-equity giant Kohlberg Kravis Roberts & Co, which, according to Bloomberg, is teaming up with David Rockecharlie, previously co-head of the energy group at Jefferies Group, and Claire Farley, a former adviser to the group, in order to build an exploration business for unconventional energy. The business reportedly would focus on shale in Appalachian and Texas shale fields. KKR's previous bet on shale gas yielded a handsome fourfold return on investment in one year. The firm funded closely-held East Resources with $350 million and agreed to sell a majority stake to Royal Dutch Shell ( RDS.A). "We're going to see a lot more private equity flow into this space," Ralph Eads, chairman of energy investment banking at Jefferies Group told Bloomberg in an interview. "There's huge demand for capital, and that capital's not all going to come from the public capital markets." Last month, KKR also revealed plans to invest $400 million in partnership with privately held Hilcorp Energy to develop a shale gas deposit in Texas. Elsewhere, Indian major Reliance Industries reportedly is mulling its third purchase in the shale gas space, and it's likely to be bigger than Reliance's previous acquisitions. In June, Reliance bought a 45% stake in Pioneer Natural Resources' ( PXD) Eagle Ford shale field for $1.32 billion. The deal followed Reliance's $1.7 billion purchase in April of a 40% stake in Atlas Energy's ( ATLS) Marcellus shale. Exxon Mobil ( XOM) and BP ( BP) are the largest owners of shale gas deposits in the U.S.