WALTHAM, MA, Southern California Gas Co. (SoCalGas) today announced it has made a $500,000 equity investment in Tecogen Inc., a developer and manufacturer of innovative, ultra-clean natural gas-driven combined heat and power (CHP) products for commercial and industrial facilities. The investment is a strategic addition to the utility company's growing clean energy portfolio.

Tecogen systems supply electric power or cooling while heat from the engine is recovered and purposefully used at the facility. The benefits may include dramatic reductions in both energy costs and greenhouse gas emissions.

"Natural gas plays a vital role in California's sustainable and low-emission energy future," said Hal Snyder, vice president of customer solutions at SoCalGas. "Innovative research projects and equity investments, like the one we're making in Tecogen, advance our leadership in helping bring to market new choices in ultra-low emissions technologies like natural gas-driven cogeneration and air-conditioning systems. These systems benefit our customers and the market by helping to reduce their energy costs and carbon footprint."

According to Tecogen officials, Tecogen has recently made significant advances in emission reduction technology that have strategic importance in regions that are particularly sensitive to toxic air-born pollution. This technology has particular importance in Southern California where the latest emissions requirements have been lowered to unprecedented levels, while becoming sufficiently strict to preclude permitting all conventionally powered combined heat and power products.

The Tecogen system has demonstrated compliance well below the emissions levels required by these new regulations both in the laboratory and through extended field trial. Tecogen anticipates commercial product availability of its advanced system in the third quarter of this year.

"California emissions standards are the toughest in the United States," said Robert Panora, president of Tecogen. "With funding from SoCalGas, Tecogen has made a scientific breakthrough that is now making it possible to produce products that deliver unprecedentedly low levels of pollutants. We appreciate SoCalGas' continuing support as we bring new products to market."

The SoCalGas investment will be used by Tecogen to bring the technology to market worldwide, said Panora.

About Tecogen

Tecogen manufactures highly efficient, ultra-clean combined heat and power products including natural gas engine-driven cogeneration and air conditioning systems for industrial and commercial use. Tecogen has an installed base of more than 2,000 units supported by an established network of engineering, sales and service personnel across the United States. For more information, please visit www.tecogen.com.

About Southern California Gas Company

Southern California Gas Co. (SoCalGas) has been delivering clean, safe and reliable natural gas to its customers for more than 140 years. It is the nation's largest natural gas distribution utility, providing safe and reliable energy to 20.9 million consumers connected through nearly 5.8 million meters in more than 500 communities. The company's service territory encompasses approximately 20,000 square miles throughout Central and Southern California, from Visalia to the Mexican border. Southern California Gas Co. is a regulated subsidiary of Sempra Energy (NYSE: SRE). Sempra Energy, based in San Diego, is a Fortune 500 energy services holding company. To learn more, go to www.socalgas.com.