Buildings Magazine - August

THE ENERGY MANAGER

Which Plug Loads Consume the Most Energy?

SEE HOW YOUR OFFICE RATES AGAINST THE TOP OFFENDERS IN ENERGY CONSUMPTION

in more energy-efficient printers, consider consolidating the ones you already have into more central locations that can serve multiple departments. Encourage staff to minimize printing whenever possible so the printer spends less time in active mode.

3) Computers. In most offices, everyone needs a computer issued to them, so it’s often impossible to make the case for having fewer computers drawing power. However, you can mitigate the damage by enforcing energy-efficient power settings that will transition the computer to a low-energy sleep mode when it hasn’t been used for a while, such as during the user’s lunch break or at night.

Think about who in your office could make
do with a laptop as well. The Federal Energy
Management Program notes that ENERGY
STAR desktops with power management
settings enabled can use 21-83 k Wh every
year compared to 221 k Wh for a less efficient
computer with no power management set-
tings. However, an energy-efficient laptop
uses 18-28 k Wh per year (or 59 k Wh for a
lower-efficiency model).

4) Computer monitors. Newer LCD screens typically consume 10-18W, according to the New Buildings Institute and the National Renewable Energy Laboratory. Invest in ENERGY STAR models when you can to make sure you’re getting the most bang for your buck.

5) Fans. Simple desktop-size fans don’t consume nearly as much energy as their cold weather counterparts, space heaters, but when it comes to saving energy and money, a watt is a watt. Personal fans often consume somewhere in the range of 4-12W.

6) VoIP phones. Most VoIP phones on the market use Power over Ethernet (PoE) rather than the more powerful and more energy-intensive PoE+. PoE consumes a maximum of 15.4W.

7) Task lights. LED task lights use 6-9W on average. That’s not much, especially if the user doesn’t need it all day, but it’s important to keep an eye on all plug loads. Task lights are good candidates for advanced power strips that will shut off everything plugged into them at a predetermined time.

8) Computer peripherals. Small peripherals like mice may only draw 0.5W. Survey occupants to see what else is plugged into their computers and adjust your energy efficiency plans accordingly.

Develop the business case for addressing plug loads by conducting an energy audit in your office and determining how much could be saved. A small investment in advanced power strips and better energy conservation policies regarding power management settings and turning machines off at the end of the day could make a significant impact.

Janelle Penny janelle.penny@buildings.com is Senior Editor of BUILDINGS.

Where does your office waste the most electricity? Each office is different, but if yours is anything like the average, you can probably make a sizable dent by cracking down on personal comfort devices and consolidating printers.

The worst offenders include:

1) Space heaters. A small personal space heater that’s designed to heat a private office or the zone immediately around the user can pull upwards of 200W. If several people in your office building are using space heaters, it adds up fast.

2) Imaging equipment, such as printers, fax machines or all-in-one models. Some commercial printer models use 30-50W on standby mode and up to 300-500W whenever they’re actively printing. If your office uses a lot of paper, that’s a lot of extra spikes in the power consumption. If you can’t invest

COMPUTERS REQUIRE A LOT OF ENERGY TO OPERATE. You probably can’t eliminate them from your office, but you can mitigate the energy drain by having occupants use power management settings.