Your produce and frozen foods could soon arrive at grocery stores in trucks that release fewer emissions. Researchers are developing a clean technology to keep your food cool while it travels.

Engineers at are working to replace refrigerated trucks' diesel-burning cooling system with fuel cells. These fuel cells mix hydrogen and air to create energy; the byproduct is water. Researcher Kriston Brooks says that means fewer greenhouse gas and particulate emissions than from diesel engines.

"From the big picture of how much carbon dioxide we produce and other emissions, it's pretty small," Brooks says. "But it's a start."

Brooks says hydrogen fuel cells are twice as efficient as the diesel engines used to cool refrigerated trucks, but they can be expensive. He and his colleagues are working to make them cheaper for companies to use. The cooling system they are currently working on — which includes a fuel cell and cooling container, — costs about $40,000. By comparison, a diesel-engine-based cooling system typically runs $20,000-$30,000. But, Brooks says, the price of fuel cells is quickly dropping.

He says people also get a little nervous when they hear the words hydrogen and fuel in the same sentence.

"We are working very hard on this project to include the hydrogen safety panel that [the Department of Energy] has set up to make sure that we're incorporating suggestions that they have so that it can be a safe technology," Brooks says.

Researchers will spend the next year testing the equipment in the lab. Field tests will take place in the summer of 2015, when trucks powered by the fuel cells will be used to transport groceries in California, Texas and New York. The goal over the 400 hours of logged run time is to assess the fuel cell's durability as it rumbles down the road.

"We wanted to verify that it would work in various climates in different times of year. Certainly it's a lot more rigorous on a fuel cell and a [transport refrigeration unit] during the summertime," Brooks says.

Several grocery facilities participating in the research already power their forklifts with hydrogen fuel cells. Experiments are also being run in buses and cars, and on grid-reliability projects. Researchers are also working on powering luggage transportation carts at airports with fuel cells.

The fuel cells, which are about the size of a breadbox, will save about 10 gallons of fuel per day per truck, the researchers say. That may not sound like much, but the hope is that if fuel cells can replace the diesel engines currently used to cool some 300,000 refrigerated trucks on the road in the U.S., the energy savings will soon add up.

This post originally appeared on Earthfix, a joint reporting project between Oregon Public Broadcasting, member station KUOW, KCTS 9 Public Television, Idaho Public Television, Northwest Public Radio and Southern Oregon Public Television.

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