Is A Full or Empty Refrigerator More Energy Efficient?

Lettuce, string cheese, and tortillas are just a few things that I regularly stack on my refrigerator’s shelves. As I ate my groceries, I often wondered if my fridge had to work harder to keep my foodstuffs cold. When a writer sent that question to the Green Guru mailbox, it gave me the perfect opportunity to look into what makes—and keepsrefrigerators frigid.
Is a full or empty refrigerator more energy efficient?
—Abbey Myszka, Emeryville, CA
It’s cool that you want to keep your fridge humming efficiently, but the amount of food you store in it doesn’t matter. “A full refrigerator doesn’t decrease energy use,” says researcher Jacob Talbot of the nonprofit American Council for an Energy-Efficient Economy (ACEEE). Your fridge’s foodstuffs most likely don’t displace enough space to reduce the amount of energy needed to keep it chilled, he explains.
There are a number of other ways, however, to reduce your refrigerator’s demand for power. These appliances use more energy than almost any other in your home (aside from air conditioners and heating equipment), so you want one that has earned the government’s Energy Star certification. And plan before you open. Keeping the door ajar while deciding what’s for dinner, or going in repeatedly, are the main reasons fridges lose their cool.
Keep your unit between 36 and 38 degrees Fahrenheit, suggests the ACEEE. Check the seals on the door to prevent leaks, and position the box away from heat sources, like ovens, dishwashers, or sunny spots—they force it to work harder. And be sure to give those leftovers time to cool before you pop them into the fridge.
One reader responded to the column, saying, “You say in your article in the latest magazine that people should get a refrigerator that ‘has earned the government's Energy Star certification.’ You should go to to look up a recent article about the Energy Star program. The government does no testing of appliances, and does nothing to check on the manufacturers' claims on energy efficiency. Another government agency sent in a lot of fake claims to the certifying agency, one of them for a fan with a feather duster on top, and they immediately received authorization to sell it as an energy efficient appliance. The ratings are totally unreliable, and LG was actually stripped of its ability to show energy star ratings at all because their claims were so far off.” See the article here.
Thank you, reader, for pointing that out. National Public Radio also reported that Energy Star wasn’t living up to its claim.
“We find that not all of the products are as efficient as they claim to be,” Celia Kuperszmid-Lehrman, deputy home editor for Consumer Reports, told the reporter.
That piece, as well as one from The New York Times, stated that in reaction, the Department of Energy will soon include third-party verification.
“By the end of the year, the government said, all tests submitted by manufacturers will have to be from independent certified labs. Until now, that had been the case for only some categories of products, including windows, doors and compact fluorescent lighting,” Matthew L. Wald and Leslie Kaufman wrote in The New York Times.
The piece went on to say that, “Gregory H. Friedman, the Energy Department inspector general, who oversaw the recent audit, expressed guarded approval. ‘If executed as described in the press release, it looks like this is a significant change to the process, which appears to address many of the issues we’ve raised in the past,’ he said, adding the issue was whether they would follow through.”
So, although the program may not have certified the most energy efficient appliances in the past, if all goes well, the Energy Star label will showcase only the most stellar devices—including refrigerators—in the future.

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