CAMBRIDGE, Mass. - TIAX, a collaborative product and technology development firm, announced that it has been selected by the U.S. Department of Energy's (DOE's) National Energy Technology Laboratory (NETL) to develop a rooftop air conditioning system for commercial buildings that will result in both increased energy savings and improved air quality.

The Department of Energy, through its Office of Energy Efficiency and Renewable Energy, Building Technologies Program, will provide approximately $800,000 in funding for the project and TIAX will cost share the remaining 20 percent.

"In order to maximize energy resources, it is necessary to explore the development of viable new air systems that reduce energy consumption and are cost-effective," said Aaron Yocum, project manager at the DOE. "We will look to TIAX to create an innovative yet practical energy system that can be easily implemented and maintained."

The first phase of the 18-month project calls for TIAX to complete a design and performance analysis of technologies and best practices of current systems that will form the basis of a prototype rooftop air conditioner with an integrated, dedicated outdoor air system.

In current air conditioning systems, fresh air from the outside is typically filtered through the same system that recirculated air is, resulting in the fresh air being mixed with the return air and reducing the dehumidification effectiveness of the air conditioner, says the company. TIAX will propose a system with two separate tracks for airflow - one track that specifically conditions the outside air, thus minimizing the amount of air to be dehumidified, and another track dedicated to conditioning recirculated indoor air.

Advantages of this proposed design are said to include better indoor air quality and better control of indoor humidity levels, resulting in a more consistent supply of ventilated air. With this system, says the company, annual energy savings of 35 percent could be achieved because the recirculated indoor airflow rate can be varied to meet the indoor cooling load without compromising the delivery of the amounts of outdoor air needed to meet indoor air quality standards.

"Due to the amount of energy commercial users consume with their air conditioning systems and the serious implications that can result from improper humidity control, such as mold growth and poor air quality, it is necessary to develop technologies that are energy efficient and environmentally sound while also cost effective," said Kenan Sahin, president of TIAX. "We look forward to working in conjunction with the Department of Energy to ensure that this type of system becomes a reality."

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Publication date: 11/24/2003