Four TECOGEN Systems Complete Successful Startup at Chabot College in California Units are Tecogen’s First to Qualify for “Simplified Interconnection” Under California’s Rule 21 WALTHAM, Mass., June 17, 2004 - Tecogen Inc. announced today that four of its 75-kilowatt cogeneration systems have been successfully installed at Chabot College in Hayward, California. The Tecogen systems are providing 100 percent of the energy required to heat Chabot’s Olympic-sized outdoor pool and 38 percent of the electricity used throughout the rest of the campus. Tecogen’s equipment, which yields almost 80 percent total energy efficiency, will significantly reduce the college’s energy costs. Experts at ACC Environmental Consultants, the firm that oversaw the installation, anticipate that the cogeneration systems will save Chabot College $1,000,000 over the next ten years. Each on-site cogeneration module contains an engine that burns natural gas to power a generator, which in turn produces electricity for the facility. Exhaust heat is recovered to provide hot water, thereby eliminating the need for any additional gas to power boilers. The technology is exceptionally clean and environmentally friendly; state-of-the-art emissions controls have allowed Tecogen to satisfy even the most stringent air quality standards in the U.S., including standards established by the South Coast Air Quality Management District (SCAQMD) in California. "When you combine Tecogen’s high efficiency ratings with the rebates that are available in California through the California Energy Commission, PG&E, and others, you can achieve some very impressive cost savings with short-term paybacks," said Jim Soles, maintenance manager at Chabot College. "For example, the 300-kilowatt Tecogen system will generate electricity for about $.05 per kilowatt hour (kWh), compared with utility-supplied electricity, which is currently costing the college $.15 per kWh". These are Tecogen’s first factory type-tested and certified units accepted by a California utility for "simplified interconnection" under the provisions of California’s Rule 21. "We were very pleased that we were able to install these units without the traditional and costly utility requirements," said Robert A. Panora, president of Tecogen. "We are especially gratified with the cooperation by the PG&E’s interconnection staff while working through this new process, and we look forward to a new era of fast-track permitting for our systems in California." In 2000, California became one of the first states in the country to establish interconnectivity standards for distributed generation (DG) technologies through the adoption of Rule 21 by the California Public Utilities Commission. Under Rule 21, specific DG systems (including Tecogen’s) can be pre-certified, which will qualify them for a "simplified interconnect" review process by the electric utilities, instead of the longer, more costly review that is required for non-certified units. In addition, requirements for secondary relay devices have been waived for Tecogen installations. These devices help protect the utility grid from interruptions and disturbances that can be caused by non-certified equipment. About Tecogen In the U.S., Tecogen is the leading manufacturer of reliable and efficient low-emission packaged cogeneration units. Based on low-cost, mass-produced internal combustion engines, Tecogen's modular units use natural gas to produce electricity right at the customer's facility, capturing the waste heat to produce domestic hot water. Tecogen has a nationwide installed base of more than 1,800 units, which it supports through an established network of engineering, sales, and service support. Tecogen is a subsidiary of American Distributed Generation Inc. based in Waltham, Massachusetts. For more information, go to www.tecogen.com. About American Distributed Generation, Inc. A privately held company based in Waltham, Massachusetts, American Distributed Generation provides a range of innovative products and services in support of the emerging market for on-site generation of electricity, heating, and cooling at commercial, institutional, and light-industrial facilities. In addition to TECOGEN® and TECOCHILL® equipment and field service, the company also offers customers a "virtual utility" option for the purchase of electricity and other energy services at prices below conventional utility rates. For more information, go to www.americandginc.com.