Compare the wattage of the small appliance with the range surface unit and consider the time and task involved to decide which to use. Ovens that cycle on and off through thermostatic controls are more energy efficient than range surface units for cooking complete meals or multiples of a food rather than a single food. Ovens should be well insulated to retain heat and conserve energy. A self-cleaning unit has more insulation and therefore retains heat better than conventional models. A microwave oven is best used for preparation of a small number of food servings and for quick heating of food.
Microwave cooking is convenient.
Whether microwave cooking is more energy efficient than conventional cooking methods depends on the length of cooking time, and the alternate method of cooking. For safety reasons, especially, keep the seal clean around a microwave oven door. The energy efficiency of a refrigerator-freezer is determined by overall size, freezer compartment size and operating temperature, insulation, method of defrosting and user habits. Buy a refrigerator large enough to serve household needs. The larger the freezer, the more energy required to maintain this temperature.