Countertop microwave ovens are relatively energy-efficient compared to traditional ovens or stovetop cooking. They utilize microwave radiation to directly heat the food, resulting in quicker cooking times and less energy wastage.nnHowever, it's important to note that the energy efficiency can vary depending on the model and usage. Look for countertop microwave ovens with energy-saving features or eco-friendly modes if energy efficiency is a priority for you.