What do vampires and cable TV boxes have common? They both suck energy (from people and power grids respectively). The electricity used by equipment and devices when they are switched off or in standby mode is commonly called standby power.
The origin of the term energy vampire is shrouded in mystery but likely refers to an external power supply also known as an A/C adapter or charger. It is black, has two prongs (teeth), and sucks electricity at night.
An estimated 5-10% of residential energy is used for standby power.1 When all U.S. households are combined standby power represents a significant amount of energy, some which is wasted unnecessarily.
National Energy Action Month and Halloween both occur in October so this month seems an ideal time to tackle energy vampires and standby power. In this first of two posts, readers will learn about standby power and how to identify energy vampires. The second post will deal with ridding our households of energy vampires while saving a few bucks.
What is Standby Power?
The electricity used by equipment and devices when they are turned off, not in use, or in standby mode is called standby power, vampire power, phantom power, no-load power, or phantom load. Standby power purposes include:
- Maintaining signal reception capability (for a remote control, telephone or network signal)
- Monitoring temperature or other conditions
- Enabling a device to switch on quickly
- Powering an internal clock (e.g. to adjust a thermostat based on time of day)
- Battery charging
- Continuous display (time, status)
In some cases standby power is necessary for equipment to function properly, in others it provides convenience for users, and sometimes it is just wasted. Let’s look at a few examples.
Almost all refrigerators draw electricity continuously. The compressor cycles on and off to maintain the temperature set by the user. When the compressor is off, electricity is used by the thermostat to sense when to turn the compressor on again. This is a case of necessary standby power.
Americans can be an impatient lot who expect devices to turn on instantly with no warm up period. A cable TV box uses standby power to enable it to receive a signal and turn on the TV within seconds whenever a user pushes the on button on the remote control. Standby power is consumed 24 / 7 for user convenience.
Then there are the external power supplies we plug into a wall outlet to charge our electronic gadgets like cell phones. Once the device is charged, the power supply may continue to draw electricity until it is unplugged from the wall. This is an example of unnecessarily wasted electricity.
Which Equipment and Electronics Consume Standby Power?
A typical American household contain 40 items that constantly draw electricity whether they are in use or not.2
Equipment and electronics that consume continuous electricity include devices with external power supplies, remote controls, soft button control panels, always on displays, or that charge batteries. Standby power usage varies and some newer equipment may draw little or no standby power. The list below provides examples of possible energy vampires.
Appliances: microwave, range, oven, refrigerator, washer, dryer, air conditioner, dishwasher.
Electronics: TV, set-top box, DVD player, desk top computer, printer, scanner, tablet computer, monitor, lap top computer, router, server, copier, cell phone, game console, digital camera, cordless telephone, telephone answering machine, speakers, audio system.
Small Appliances, Tools, and Other Devices: cordless power tool, coffee maker, garage door opener, alarm clock, electric razor, thermostat.
What is the Environmental Impact of Standby Power?
One way standby power impacts our environment is through waste. Producing power uses resources from making the generating equipment to transmitting the electricity. Allowing devices to use power unnecessarily wastes the resources that went into producing it.
A major impact of standby power is the pollution and greenhouse gases emitted by fossil fuel burning power plants that generate electricity for our homes. In 2011, 68% of U.S. electricity was generated by burning fossil fuels (1% petroleum, 25% natural gas, 42% coal).3 Standby power accounts for more than 100 billion kilowatt hours (KWHs) of U.S. electricity consumption and more than $10 billion in annual energy costs. 4
Let’s put this in perspective.
The average U.S. household uses 11,280 KWHs of electricity a year.5 Generally 4 people constitute an average household used for such calculations, so each person accounts for 2,820 KWHs. Our 100 billion KWHs of standby power could provide the annual power needs of 35,460,993 Americans (11% of our population) or the entire country of Canada (35,158,304 people).6
If the electricity used to generate our 100 billion KWHs of standby power comes from a fossil fuel burning power plant, the figures below show how much coal, natural gas, or petroleum would be burned to produce 100 billion KHWs of electricity (based on data from EIA7).
- Coal: 107,000,000,000 pounds (billions)
- Natural Gas: 100,000,000,000,000 cubic feet (trillions)
- Residual Fuel Oil: 8,000,000,000 gallons (billions)
As you can see when we add all our household energy vampires together across the U.S. standby power represents a significant amount of greenhouse gas emissions and wasted energy.
In the next post, we’ll find out what we can do about energy vampires and wasted standby power.
- U.S. DOE – 3 Easy Tips to Reduce Your Standby Power Loads
- Lawrence Berkeley National Laboratory – Standby Power FAQs
- U.S. Energy Information Administration – Electricity in the United States
- ENERGY STAR – Celebrating 20 Years of ENERGY STAR, Product Retrospective: Standby Power
- U.S. Energy Information Administration – How much electricity does an American home use?
- Wikipedia – List of countries by population
- U.S. Energy Information Administration – How much coal, natural gas, or petroleum is used to generate a kilowatt-hour of electricity?