Halloween night is when ghouls and goblins hit the streets, but beware -- there are vampires already lurking inside your home. Energy vampires, that is, or electronic appliances that drain power even when turned off. If you aren't careful this wasted energy (also known as phantom loads) can turn your electricity bill into something out of a horror movie.

Energy vampires can lurk in every room. Some of your devices are designed to draw power even while off by going into standby mode, in order to receive remote control transmissions or keep digital clocks running. Portable devices that use rechargeable batteries, like laptops and phones, will also consume electricity as long as they are plugged in, even after they are fully charged. Big screen TVs with “instant on” features are also notorious energy suckers.

Any one appliance might only draw a small amount of power, but when you consider how many TVs, computers, stereos, kitchen devices and other electronic items are found in the average American home, the totals start to add up quickly. Coffee makers, electric toothbrushes, fax machines and modems all seem so innocent until it's time to write the monthly check to your power company.

In total, households in the United States consume more than $10 billion in vampire electricity annually, or about $100 per household, according to Energy Star, an energy efficiency program established by the Environmental Protection Agency. That comes to as much as 10 percent of overall home energy use. In addition to higher bills, this waste also harms the environment. Phantom loads account for about 100 billion kilowatt hours per year nationwide, adding considerably to carbon dioxide and other pollution released into the atmosphere.

That's not all: in rare cases, appliances drawing standby power can actually catch fire, especially older models that happen to be kept in damp environments.

It may not be possible to eliminate vampire energy entirely, since some devices such as answering machines, security systems and programmable thermostats rely on a continuous stream of power to perform their basic functions. However, by following a few tips you can reduce the amount of power you waste, saving money and lowering your ecological footprint at the same time:

Take the time for these basic measures and make sure the only vampires and phantoms you encounter this Halloween are the ones that knock on the door to say “trick or treat!”