Which type of refrigerator uses the most energy annually?

The large 20 cubic ft two-door automatic defrost refrigerator typically uses the most energy annually due to its size and the features it includes. Larger refrigerators have greater internal space which requires more energy to maintain the desired temperature. Additionally, automatic defrost models utilize heating elements to periodically warm the internal surfaces and melt frost build-up, which consumes extra energy.

In contrast, single-door refrigerators and mini-refrigerators are smaller and generally less energy-intensive, while freezer-only units can also be more energy efficient than their full-sized counterparts, depending on their design and usage. The combination of size, the automatic defrost feature, and the need to maintain consistent temperatures in a larger volume of food categorizes larger, two-door refrigerators as the highest energy consumers among the options presented.