Standby Power
Use of electronic devices such as televisions, computers, microwave ovens and entertainment units has climbed substantially in recent years. In addition to increased power consumption, these devices have introduced a phenomenon known as standby power or ghost power. Standby power is defined as the lowest level of electricity consumed by appliances that cannot be switched off (influenced) by the user, and may persist for an indefinite time when an appliance is connected to the main electricity supply. It is estimated that 46,000 kilowatts of standby power is used in Alberta.Standby power can include electricity used while the product is not performing a function or when it is performing one or more functions. For example, even though turned off, standby power is used to operate a clock in a radio or microwave oven or it is used in a DVD player that has a LED (light emitting diode) readout.
Natural Resources Canada’s (NRCan) Office of Energy Efficiency has set minimum performance standards for standby power. It is estimated standby power accounts for up-to-10 per cent of the average annual electrical consumption in Canada. The proposed time table for these standards can be viewed on their website.
Televisions
Televisions (TVs) are one of the biggest users of electronic electricity due to:
- high saturation (multiple units in the home)
- increasing TV sizes
- related standby power use
There are two methods to determine TV power use ratings. The first is connected load rated in watts. The second method, which is considered a fairer comparison, is power consumption on a watts-per-square-inch rating. Most new TVs today come with a power-saver mode that can drastically cut power consumption.
|
TV Type |
Connected load in watts |
Watts per square inch |
|
Rear projection |
208 |
0.13 |
|
Liquid Crystal Display (LCD) |
193 |
0.27 |
| Plasma |
328 |
0.34 |
| Cathode Ray Tube (CRT) |
146 |
0.34 |
Note: these are averages; there will be variances depending on manufacturer.
Since July 1, 2005, all TVs, VCRs, DVDs sold in Canada must meet the Energy Star® criteria of equal-to or less-than one watt in standby mode.
Microwave Ovens
Microwave ovens use large amounts of standby power compared to their overall use. Even though a microwave oven heating food uses more than 100 times as much power as running a clock, it sits idle in standby mode 99-or-more per cent of the time. It is estimated in one year, microwave ovens consume more electricity in the standby mode than when the unit is in use.
Recommendations for Standby Power
- Install a power bar on electronic devices that allows them to be turned off with a single switch. (There are some exceptions such as TV set-top boxes, because cable companies may require continuous power to maintain service.)
- Turn on the power saver mode; most TVs come with it turned off. (Check the TV manual.)
- There may be a feature to control the intensity of the backlight for LCD TVs. This offers two benefits:
- Lower brightness uses less power
- Lower level of backlight improves image quality
- When possible, switch off the power to any device when not in use.
- Look for the Energy Star® label when buying a new electronic product. This ensures the most energy efficient device available.
