In the cold fall and winter months, your car's average miles per gallon can decrease as much as 22 percent. The reason? Colder air is denser, which adds drag, along with a bigger culprit: heat. All the energy used to warm the car plus the defrosters, heaters and seat warmers gobble up gas. To be more fuel-efficient, try to park your car where it's slightly warmer, like a covered garage. If you have a plug-in vehicle, while it's charging, turn on the seat warmers to pre-warm the car so it doesn't drain the battery. And the easiest tip? Remove roof racks: They increase wind resistance in any kind of weather.

For many of us, the computer has become an essential part of our work life, both at the office and at home. When you're not on your laptop or desktop, it often goes into something called "sleep mode" to conserve energy, but it can be "woken up" with the stroke of a key. If you want to save energy when using your computer, you should turn off the monitor on your desktop if you aren't going to use it for more than 20 minutes. If you plan to not use your computer for more than two hours, you should shut down the whole system completely. Even though there is a small amount of energy used to turn on a computer, it's not as wasteful as having it in sleep mode for long periods of time.

It can be hard to detect air leaks where cold air is blasting inside during the winter months, and the United States Department of Energy has two easy tips to find out if there are leaks in your house. First, turn off all the indoor and outdoor lights, and use a flashlight to shine on potential gaps inside the house. Have someone outside to observe the house as you shine the light; large cracks in the house will show up as rays of light. Second, grab a dollar bill and shut a door or window on it. If you can pull it out and it doesn't drag, the window or door needs to be weather-sealed.