You can save energy and reduce utility costs by purchasing energy efficient heating and cooling appliances and installing programmable or smart thermostats. These let you set your HVAC system according to when demand is higher, so less energy is used when, for example, you are at work or on vacation. Insulating your home, sealing air leaks, and installing energy efficient windows can also help you control energy costs. But not all strategies involve an investment. You can lower energy costs by replacing older lightbulbs with LEDs, or adjusting your habits by turning off electrical fixtures and appliances when not using them, hang-drying clothes, or washing dishes by hand.