Have an old refrigerator? Always forget to turn the lights off? Crank up the air conditioning, then leave for work? While you can't completely eliminate your energy bills unless you invest in a renewable energy system such as solar power, you can use several techniques to drastically reduce energy prices on your next bill. Some of these changes are so simple, you can do them in the time it'd take to say, "How did my energy bill get so high?"

Switch Appliances to Energy Star Compliant Models

Energy Star reports more than 60 million refrigerator units in the United States are 10 years old or more. The older an appliance gets, the more prone it is to drawing more power than it needs due to inefficient systems, as well as having older technology that's not as efficient. Any Energy Star appliance is required to draw 15 percent less power than a non-certified model, so you get savings right off the top.

Use Motion Sensor Lights Inside

Plenty of people use motion sensor technology outside of the house for security and safety purposes. However, how many people take that technology and put it to practical use indoors? The Daily Green recommends motion sensors so the lights automatically turn off and on as you enter and leave rooms. This doesn't work in a lot of situations, such as houses with pets, but it's well worth considering if remembering to turn off the lights when you leave a room just isn't forming into a habit for you.

Turn Off Water Heater

The hot water heater keeps hot water always available, but if you aren't going to be around to use it, there's no point in keeping it heated. However, turning it off and on is a bit more complicated than it appears. Most people have a very similar schedule with their showering and work routine. If these electricity customers all flipped their water heaters on at the same time, it could lead to an unreasonable demand on the power grid. For that reason, a water heater timer is a good investment. It automatically turns your water heater off and on according to a schedule that you set. Time the water heater to come on during off-peak hours, instead of right when everyone wakes up or gets home.

Use Bare Minimum of Heating and Cooling

In most areas, you can go without air conditioning at certain times of the year. Fan technology, such as vortex fans, offers a powerful focused alternative to whole house and window air conditioning units. Thermal curtains, well-insulated houses and plenty of house shade also help make this a reality. In the winter, you do need to keep your heat at 50 degrees F or higher to avoid any problems with your water pipes. Other than that requirement, you can keep it exactly where you feel most comfortable. If you really can't go without heating or cooling but you want to cut down on your bill, using a space heater or window air conditioning unit in one room is preferable to heating or cooling the entire house.