Homeowners interested in making a serious push toward energy efficiency are likely already aware of some of the bigger electricity hogs around the house: Keeping lights on, running the air conditioning all day and poorly insulating the property. But you'd be surprised at how many devices in your home are making significant contributions to your utility bills. Some of the least known but worst offenders of household energy consumption are your modem and router.

A new study from the Natural Resources Defense Council (NRDC) found that household internet networks – which number 145 million modems and routers across 88 million homes in the United States – consume over 8.3 billion kilowatt-hours of electricity. The environmental group calculated the cost of this consumption at $1 billion, equal to the annual cost of three coal power plants' worth of electricity. Despite their small size, these network devices can actually consume even more energy than your TV or computer.

Even worse, whereas lights, air conditioning and similar utilities can be shut off, modems and routers run all day long, even if your computer is hibernating. The total environmental impact of this energy use comes at five million metric tons of carbon dioxide. The Energy Collective, a group of climate and energy analysts, found this amount of carbon emissions equal to the total output of 1.1 million cars.

Routers and modems are among the biggest consumers of energy around the house, and homeowners should take steps to replace them with more efficient models. But these aren't the only electricity drains to be discovered in your home. Virginia residents interested in learning more should make an appointment with Virginia home inspectors. These contractors will find your property's largest power drains and help to resolve them, bringing down your bills in the process.