Long Term Relationship Results in Repeat Chiller Sale to

WALTHAM, MA --(Marketwired - November 06, 2017) - Tecogen® Inc. ( NASDAQ : TGEN ), a clean energy company providing ultra-efficient, clean, natural gas powered on-site power, heating and cooling equipment, is pleased to announce that St John's Riverside Hospital in Yonkers, NY has agreed to purchase two Tecochill 400-ton DTx series chillers. The sale includes a long-term service contract. The new equipment will replace two R-22 chillers that Tecogen installed and has serviced since 1995 and have reached the end of their useful lives. It will also be an upgrade in cooling capacity from 700 tons to 800 tons.

St John's has qualified for incentives from Con Edison's Demand Management Program (DMP) that will substantially reduce the project cost and boost its overall rate of return. DMP seeks to reduce the load on the grid during periods of peak summer cooling demand by enabling Con Ed customers to install and utilize technology, such as Tecochill, that reduces the need to pull power from the grid. This contrasts with temporary load shedding via demand response.

"The chiller plant is often considered the 'heart' of a building's HVAC system, which can equal 40 to 60% of the total building's electric load," stated Michael Palmiero, Director of Plant Operations & Engineering for St John's Riverside Hospital. "Using Tecogen gas-driven chillers allows us the ability to take a lot of strain off the grid and off our own electrical distribution system while providing us the ability to use a more reliable utility to power the facility's chiller plant. The existing Tecogen equipment has been providing us almost a quarter century of reliable performance in a critical hospital environment. The proven reliability of the Tecogen equipment coupled with the company's excellent support and service team made the decision to choose Tecogen easy when it came time to replace the existing units."

Jeffrey Glick, Vice President of Sales for Tecogen, said, "It's always reassuring when a long-standing customer such as St John's Riverside Hospital decides to continue a relationship. The existing chillers have operated reliably for over twenty years. The fact that the hospital chose us when the time came for an upgrade speaks volumes to the quality of both our products and our service."

Co-CEO of Tecogen Benjamin Locke stated, "Sales of our Tecochill line of water-cooled chillers continue to grow rapidly. Their unique ability to utilize inexpensive and abundant natural gas enables customers to dramatically reduce their electrical needs while at the same time ensuring a reliable and inexpensive supply of cooling and hot water. As this instance highlights, utilities such as Con Ed put tremendous value on de-stressing the grid through products like Tecochill. We're happy to be part of the solution."

About Tecogen Tecogen® Inc. designs, manufactures, sells, installs, and maintains high efficiency, ultra-clean, cogeneration products including natural gas engine-driven combined heat and power, air conditioning systems, and high-efficiency water heaters for residential, commercial, recreational and industrial use. The company is known for cost efficient, environmentally friendly and reliable products for energy production that, through patented technology, nearly eliminate criteria pollutants and significantly reduce a customer's carbon footprint.

In business for over 30 years, Tecogen has shipped more than 2,500 units, supported by an established network of engineering, sales, and service personnel across the United States. For more information, please visit www.tecogen.com or contact us for a free Site Assessment .

Tecogen, InVerde, Ilios, Tecochill, Ultera, and e ⁺ , are registered trademarks or trademark pending registration of Tecogen Inc.

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