Three more companies have agreed to invest a total of $150 million in Clean Energy Fuels Corp., according to a recent announcement from the company.

The new investors are Springleaf Investments Pte. Ltd., a wholly-owned subsidiary of Temasek Holdings Pte. Ltd.; Lionfish Investments Pte. Ltd., an investment fund managed by Seatown Holdings International Pte. Ltd., both based in Singapore; and Greenwich Asset Holding Ltd., a wholly-owned subsidiary of RRJ Capital Master Fund I, L.P.

The $150-million investment is in the form of 7.50% convertible notes due in 2016. The notes will be convertible into shares of Clean Energy common stock at $15 per share. Chesapeake Energy Corp. also recently invested $150 million in Clean Energy to support the natural gas highway program.

Clean Energy noted that the three new investments are intended to broadly support the company’s fueling infrastructure building program, including the development, construction and operation of liquefied natural gas (LNG) and compressed natural gas (CNG) fueling stations. The monies will also help to fund the related support, management, maintenance and marketing of those stations, including the development, construction and operation of offloading facilities, related production assets and delivery trucks.

“This investment by Temasek, Seatown and RRJ demonstrates their confidence in the opportunity for fueling natural gas vehicles as well as in Clean Energy’s position as the leader in growing this market,” said Andrew J. Littlefair, president & CEO of Clean Energy. “Our development program for fueling station-building is expanding rapidly and we welcome the support provided by the funds.”

“We are steadily adding stations serving fleets in the refuse, transit, airport, municipal and regional trucking markets around the country as well as through our recently announced build out of the backbone of America’s Natural Gas Highway for trucking,” added Littlefair.

“We are honored to be a strategic partner of Clean Energy,” said Richard Ong, chairman & CEO of RRJ Capital. “We like the long-term prospects of the company. Clean Energy has been demonstrating a strong track record in natural gas fueling services in North America. It is well-positioned to tap into the future growth opportunities in both the domestic market and in international markets such as China and Southeast Asia.”

Clean Energy currently fuels over 23,300 vehicles at 248 strategic locations across the United States and Canada with a customer base in the refuse, transit, trucking, shuttle, taxi, airport and municipal fleet markets.