Microwaves are more efficient than ovens

Slate - Are microwave ovens good for the environment?

This article by the Green Lantern is a discussion of the energy costs of using the microwave versus a conventional oven. First, a comparison between ovens: gas ovens are less efficient than electric ones in cooking your food, but the cost of electricity delivery to your home outweighs the efficiency of an electric oven, making the gas oven superior by comparison. Studies in energy use between ovens and microwaves have found that small portions cooked in the microwave offer far more savings than trying to cook larger ones, yet even stove-cooking enough for 4 can cost 1.5-2.5x the energy that a microwave will use. Overall, energy used for cooking is estimated to use only 3% of a household's consumption in the US.