Schlumberger Ltd. led a $23.5 million investor round for Hayward, CA-based Alphabet Energy to help the company expand production of its Power Generating Combustor (PGC) system, which helps to reduce natural gas flaring. Alphabet, whose investors also have included Encana Corp., said Schlumberger participated with GM Ventures, Osceola Capital Management LLC, TGP, Claremont Creek Ventures and the California Clean Energy Angel Fund. Alphabet is commercializing a waste heat recovery technology initially developed at the Lawrence Berkeley National Laboratory. The PGC system is designed to eliminate the need for diesel- and natural gas-powered generators and electrical grid connections at well pads to reduce fuel, rental and maintenance costs, and to eliminate emissions. Alphabet also has opened a Houston office to keep pace with energy industry demand for remote power generation solutions.