Unplug seldom-used appliances, like an extra refrigerator in the basement or garage that contains just a few items. You may save around $10 every month on your utility bill.
Unplug your chargers when you're not charging. Every house is full of little plastic power supplies to charge cell phones, PDA's, digital cameras, cordless tools and other personal gadgets. Keep them unplugged until you need them.
Use power strips to switch off televisions, home theater equipment, and stereos when you're not using them. Even when you think these products are off, together, their "standby" consumption can be equivalent to that of a 75 or 100 watt light bulb running continuously.
Set Computers to Sleep and Hibernate
Enable the "sleep mode" feature on your computer, allowing it to use less power during periods of inactivity. In Windows, the power management settings are found on your control panel. Mac users, look for energy saving settings under system preferences in the apple menu.
Configure your computer to "hibernate" automatically after 30 minutes or so of inactivity. The "hibernate mode" turns the computer off in a way that doesn't require you to reload everything when you switch it back on. Allowing your computer to hibernate saves energy and is more time-efficient than shutting down and restarting your computer from scratch. When you're done for the day, shut down.
Take Control of Temperature
Set your thermostat in winter to 68 degrees or less during the daytime, and 55 degrees before going to sleep (or when you're away for the day). During the summer, set thermostats to 78 degrees or more.
Use sunlight wisely. During the heating season, leave shades and blinds open on sunny days, but close them at night to reduce the amount of heat lost through windows. Close shades and blinds during the summer or when the air conditioner is in use or will be in use later in the day.
Set the thermostat on your water heater between 120 and 130 degrees. Lower temperatures can save more energy, but you might run out of hot water or end up using extra electricity to boost the hot water temperature in your dishwasher.
Use Appliances Efficiently
Set your refrigerator temperature at 38 to 42 degrees Fahrenheit; your freezer should be set between 0 and 5 degrees Fahrenheit. Use the power-save switch if your fridge has one, and make sure the door seals tightly. You can check this by making sure that a dollar bill closed in between the door gaskets is difficult to pull out. If it slides easily between the gaskets, replace them.
Don't preheat or "peek" inside the oven more than necessary. Check the seal on the oven door, and use a microwave oven for cooking or reheating small items.
Wash only full loads in your dishwasher, using short cycles for all but the dirtiest dishes. This saves water and the energy used to pump and heat it. Air-drying, if you have the time, can also reduce energy use.
In your clothes washer, set the appropriate water level for the size of the load; wash in cold water when practical, and always rinse in cold.
Clean the lint filter in the dryer after each use. Dry heavy and light fabrics separately and don't add wet items to a load that's already partly dry. If available, use the moisture sensor setting. (A clothesline is the most energy-efficient clothes dryer of all!)
Turn Out the Lights
Don't forget to flick the switch when you leave a room.
Remember this at the office, too. Turn out or dim the lights in unused conference rooms, and when you step out for lunch. Work by daylight when possible. A typical commercial building uses more energy for lighting than anything else.