Private equity investment advisory firm Tridevi Capital has agreed to invest US$20 million in Prabha Energy (PEPL), a subsidiary of Bombay Stock Exchange- and National Stock Exchange-listed oil and gas exploration company Deep Industries. Tridevi made the investment through a subscription of compulsorily convertible debentures, which will represent a 40 percent equity stake in PEPL upon conversion. PEPL will use the new funds to develop a coal bed methane block in Jharkhand, in which the company holds a 25 percent interest. The transaction is subject to customary closing conditions.