If outside temperatures are warmer, it takes more energy to cool food. This could be a problem:

It’s easy to take the huge variety of foods available at the grocery store for granted. But it’s possible because of the technology—and huge amount of energy—that keeps dairy, meat, fruits, and vegetables cold, safe from rot, and free of bacteria growth. To find out how the heat is affecting the process of keeping things cool, I talked to Nicola Twilley, the author of Frostbite: How Refrigeration Changed Our Food, Our Planet, and Ourselves. Our interview has been condensed and edited for clarity…

The estimate is that for every degree-Fahrenheit rise in ambient temperature, your refrigerator uses 2 to 2½ percent more energy. So it’s significant. It has to work significantly harder to cool things. So there is a real problem…

We can’t just store our food at a much warmer temperature. But there actually is a big push to raise the temperature that frozen food is stored at by a couple of degrees. Currently frozen food should be transported at minus 18 degrees Celsius, or zero degrees Fahrenheit. But for every degree that you go below minus 12 degrees Celsius, you’re using an extra 2 or 3 percent energy.

The company that owns Birds Eye [the frozen foods giant] has studied this and found that if their foods were stored at minus 15 degrees centigrade, rather than minus 18, it wouldn’t affect the food safety or the texture or taste or nutrition level. And it would likely reduce energy consumption by about 10 percent, which is a lot. All the big frozen-food warehouses and shipping companies are behind this right now.

It sounds like transporting frozen food at slightly warmer temperatures could work.

But there are bigger issues at play here. How much frozen food should there be and how far should it be shipped? How about refrigerated food? Americans are pretty used to all sorts of cold and frozen food options that come from who knows where.

Talk about needing more local food has been going on for a while. Some had concerns about oil use; what does it take to transport food thousands of miles to please consumers elsewhere in the globe? Or it might be about agriculture more broadly: do people eat what is available each season instead of depending on food grown elsewhere that makes certain food available all year round?

I would guess many American consumers still have little idea where their food – fresh or frozen – comes from. It is just available. I can go roughly two and a half miles from where I live and visit five different sizable grocery stores. Expand that radius to five miles and it adds numerous stores. What if I had fewer shopping options, whether in terms of locations or fewer food items when shopping in each store?

It is interesting to hear that companies might be willing to make changes as it could save money and be more sustainable. What other parts of the system, whether at the policy level or for those who transport goods or on the consumer side, would address the issue of energy use for frozen and cold food?