With the frenetic pace of the winter holidays, urban farmers looking for ways to save time in their preparations may also have an opportunity to save energy when reheating frozen, made-ahead holiday meals.
The Electric Power Research Institute recommends keeping these two things in mind when thinking ahead to pre-made holiday meal preparation: Be flexible in choosing your dishes, and when possible, use the microwave or toaster oven instead of the conventional oven.
EPRI assessed the energy required for reheating meals using a microwave, toaster or conventional oven at its Energy Efficiency laboratory in Knoxville, Tenn., and found significant differences. If you reheat meals, a microwave would be the most efficient way to cook them.
For energy-conscious cooks, the energy savings can add up. For example, in the study, EPRI found that reheating a frozen lasagna dinner in the microwave uses 253 kilowatt hours compared to 716 kilowatt hours in a conventional oven. But a lemon pepper fish dinner, according to the study, may be an even more energy-efficient option, taking 102 kilowatt hours to reheat in the microwave and 513 kilowatt hours to reheat in a conventional oven.
The time saved by using a microwave is an added bonus. For example, cooking a frozen submarine sandwich that required 2 minutes 45 seconds in a microwave required 23 minutes in a toaster oven or conventional oven.
Individual differences in energy savings are small, but the true extent of the power consumed is impressive when calculated nationally. If the 34 million American households estimated to regularly consume single-serving frozen pizzas cooked two of them per week in a microwave instead of an oven, it would save 1.5 billion kilowatt hours of electric energy per year—enough to power New York City’s 3.2 million residential electricity customers for one month. Alternatively, by switching from conventional electric ovens to toaster ovens, approximately 680 million kilowatt hours of electric energy could be saved per year.