Page: 1 - 2

The Big Chill - Page 2

The technique works even better in humid areas where ice builds up on the evaporator coils more frequently and the defrosting mechanism becomes activated more often, said Navaz. With less infiltration there is less ice build up and less energy to run the auto defrost function.

“We are making a known technology better and there is a potential for huge payoff,” he said, adding “just multiply our results by the number of display cases used state wide, nation wide and world wide.”

Manufacturers implementing changes based on the Kettering research are already seeing better than predicted results, according to Navaz, and so far it hasn’t cost them anything to implement the recommended changes. Edison in California conducted the field tests of Navaz’s research for manufacturers and users in the state.

The POCAC tests different scenarios in terms of geometrical configuration and turbulence levels throughout the cold air curtain in refrigerated display cases that cause infiltration of warm air into display cases. Mazyar Amin designed and built the POCAC machine.
In addition to energy savings, lowering the pressure on the compressor also extends the life of the compressor and creates more cost savings over the long term.

“This is not something we are promising,” said Navaz, “it is something we have done and proven.”

The Department of Energy and the California Energy Commission and Edison underwrote the research project that began 1998 with a simple computer simulation of air curtains. The total cost of the project came in just under $500,000, according to Navaz.

Partnering organizations for the cold air curtain project included The Technology Test Center (TTC) at Edison and Public Interest Energy Research (PIER) at California Energy Commission.

The next step is researching the cold air turbulence, according to Navaz. “If we can fix it at the discharge air grille we can achieve another 10 to 15 percent improvement in energy efficiency,” he said. They will need to secure funding to perform the turbulence research.

Calling infiltration a bad thing in general, Navaz envisions making all refrigeration more energy efficient, including walk-in freezers and coolers in restaurants, horizontal refrigeration and freezers with doors.

“There are so many in service and infiltration is a huge issue,” he said. “Imagine if we could save 10 to 15 percent in all of these. What an impact that would make on energy consumption world wide,” he added. He is currently attempting to form a consortium with Edison to expand the research and create jobs in Michigan by starting a center for Efficient Refrigeration Technology

Recognizing the push to develop alternative energies, Navaz believes his refrigeration research is part of a larger energy picture. “It doesn’t mean we shouldn’t develop new technologies simultaneously,” he said, “but this is an easy, very low-cost/low-risk way to help to reduce energy consumption immediately.”

To request an issue of Kettering Perspective, contact us at
Kettering Perspective, Office of PR & Communications, 1700 West Third Avenue, Room 4-934 CC, Flint MI 48504.
810 762-9538 voice; 810 762-7435 fax; gerwin@kettering.edu