We get a lot of questions from readers asking what they can do personally to help combat climate change.
Start in the kitchen, with the elephant in the room — The Refrigerator.
Recommendations vary slightly among government agencies and consumer groups, but the proper temperature for a household refrigerator is 37 to 40 degrees Fahrenheit (3 to 4 degrees Celsius). There is less disagreement about proper freezer temperature: 0 degrees Fahrenheit (minus 18 Celsius). What about increasing those temperatures somewhat, to save energy (and money)? While it might be tempting, it's not a good idea. Fresh food will spoil sooner, and frozen food will decline in quality more quickly. You certainly don't want to waste food, or worse, risk food poisoning.
Randy Worobo, a professor of food microbiology at Cornell University, said higher temperatures in the refrigerator accelerate the growth of pathogens that are already in the food. Of particular concern, he said, is the bacterium that causes listeriosis, a potentially fatal infection. “It can be at very low levels, but by increasing the temperature you can dramatically increase the growth rate,” he said. Adding to the problem, Dr. Worobo said, is that many people keep their refrigerators too warm to begin with. A 2015 study in Britain, for example, found that half of refrigerators in older adults' homes were above the recommended temperature.
Consumers may not be entirely to blame for this. Many refrigerators with simple thermostat dials are not easy to set precisely, and even new models with digital readouts can be off.
All of this suggests a safer way to potentially save money and contribute, however slightly, to saving the planet: Invest $5 or $10 in an appliance thermometer, which can accurately tell you how cold the fridge and freezer compartment really are; you can then adjust the settings as needed. I recently bought a pair of thermometers and they showed that both the refrigerator and freezer compartments of my year-old KitchenAid were several degrees colder than their digital settings.
But Dr. Worobo said the easiest way to reduce your kitchen-carbon footprint — at no cost — is to have your mind made up before you open the refrigerator. “Don't stand with the door open, making decisions about what you want to eat,” he said. “That is where their biggest energy consumption is.”