When storing leftovers in the refrigerator, it's imperative to cover the food to keep it fresh. But did you know covering your food also helps save energy? A refrigerator has something called a compressor; its job is to keep the air inside the fridge cool. Moist air in the refrigerator is harder to keep cool, so the compressor has to work harder. Uncovered food emits moisture, and over time, it uses more energy. Investing in reusable silicone covers or foil to cover food is a simple and easy way to help save energy and money.