Tires should be inflated to the pressure recommended for your vehicle; this information is often printed inside the door frame or in your owner's manual. For every 3 pounds below recommended pressure, fuel economy goes down by about 1 percent. Tires can lose about 1 pound of pressure in a month, so check the air pressure regularly and always before going on a long trip or carrying heavy loads. Underinflated tires can also detract from handling, safety, and how long the tires will last.

For one thing, a pitcher full of water will help your refrigerator keep your food cool more efficiently, much like how a cold ice pack works in a cooler. Also, whenever you want a glass of water, you won't have to let the tap run for a few moments to obtain a cool temperature, cutting down on waste. Plus you won't need as much ice, which requires energy to make.