Competing to create a more energy-efficient air conditioner

Cooling challenge spurs more energy-efficient air conditioner
The Voyager DC, a hybrid rooftop air conditioner from Trane, Inc., achieved Western Cooling Challenge certification from the UC Davis Western Cooling Efficiency Center. It is 40 percent more energy efficient than conventional units. Credit: Trane, Inc.

A University of California, Davis, challenge to build more energy efficient air conditioning has spurred a major global manufacturer to build a rooftop air conditioner that is 40 percent more energy-efficient than conventional units.

Trane, a provider of heating, ventilating and air conditioning systems, is the second manufacturer to achieve Western Cooling Challenge certification. The challenge, established in 2008 by the UC Davis Western Cooling Efficiency Center, is the most demanding certification of its kind. It aims to help manufacturers develop more efficient cooling technologies, particularly for hot, arid climates, such as in California. The program also helps building owners install and use those products.

Trane achieved UC Davis certification for the DC, a hybrid rooftop that uses indirect, evaporative cooling to increase cooling capacity and reduce peak electrical demand.  

Following laboratory testing, the equipment was verified by the UC Davis Western Cooling Efficiency Center.

Cooling challenge spurs more energy-efficient air conditioner
Former UC Davis Western Cooling Efficiency Center director Dick Bourne and Thomas Stiles, from lab testing company Intertek, examine Trane's DC Voyager cooling unit. The unit achieved Western Cooling Challenge certification from WCEC. It is 40 percent more energy efficient than conventional units. Credit: Jonathan Woolley/UC Davis

"Since air conditioning is the largest portion of electricity used during , the potential for 40-percent savings is enormous," said UC Davis Western Cooling Efficiency Center associate engineer Jonathan Woolley. "Many are not yet aware that new electric utility rates will saddle commercial building owners with large additional charges for power used during peak periods. Trane's Voyager DC met our on the mark, and promises to be one of the most cost effective, climate-appropriate cooling technologies available for ."

Much as sweat cools the , the Voyager DC uses to cool outside air for the condenser on an otherwise conventional air conditioner. The air conditioner then uses the water chilled by evaporation to cool the hot outside air used for building . Such techniques increase the number of hours a system can use "free cooling" to cool a space, and dramatically reduce the amount of time a system has to operate at full speed. In addition, the Trane Voyager DC incorporates variable speed fans, staged compressors, and other measures to maintain high efficiency rates.

For a product to be Western Cooling Challenge certified, it must be at least 40 percent more efficient than Department of Energy 2010 standards.

Entries must also be market-ready. Trane is the first major manufacturer to enter the challenge, reflecting an industry interest in marketing air conditioning systems that are designed for specific climates.

The other winner, in 2009, was Coolerado Corp. of Denver, Colo.

The California Public Utility Commission's Statewide Energy Efficiency Strategic Plan calls for the rapid commercialization of cooling technologies that are adapted for dry, hot climates. The plan specifies that 70 percent of air conditioners installed in 2020 should be "climate appropriate."

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UC Davis challenge produces a better air conditioner

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Citation: Competing to create a more energy-efficient air conditioner (2012, November 9) retrieved 15 October 2019 from
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User comments

Nov 09, 2012
This is definitely one of those "why weren't we doing this decades ago?!" ideas. Still, better late than never. I'm excited.

Nov 09, 2012
How dare these filthy scientists attempt to distort the marketplace with their scientific meddling.

Free Market air conditioning is already perfectly optimal in every way. Libertarian/Randite/Austrian economics proves it.

Nov 10, 2012
In desert climates tenant-building owners and developers may be abandoning central-air designs, since manufacturers choose materials for the Gov-mandated high-efficiency central-air systems that rust out in the field within a year.

While some of this equipment is under warranty, the most expensive part, the removal and re-installation is not.

Consequently, in California rather than replace old central systems, I'm seeing annoyed small-building clients ask me to abandon & replace these system with removable-wall or window-AC units for summer, and portable-electric heaters for winter.

Nov 10, 2012
Gee sounds like:

free market 1.

Socialist/keneysian/communists 0.

Who'd have ever imagined!

Nov 10, 2012
Communism kept market from overheating so no air conditioner was needed.

Nov 11, 2012
@lengould100: yeah, this system's requirements are listed as good for "dry, hot climates" but it should be listed as good for dry, hot climates with a cheap water available. I'm not sure there are many such climates. I know where I live it's hot but also humid so you can't regularly ventilate a building because that would cause mold and be very uncomfortable. Besides, why not just use solar cells to power conventional AC? That's efficient in terms of how much energy you're using from the grid.

How about this idea: would it be possible to design something that cooled the air around the outside part of a window AC? Then you could keep the window AC operating at optimal conditions for maximum performance.

Nov 11, 2012
Taking advantage of the natural environment to reduce energy consumption will be growing more and more common.

For example, refrigerators will soon be using outside winter cold air temps to keep their interiors cold.

It isn't rocket science, but it is incomprehensible to retards.

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