Saving Energy - Public Works - Department of Administration

Conserving Energy

Appliances

Appliances that are used only periodically, but remain plugged in or turned on permanently, use energy the whole time. Follow these steps to help increase efficiency:

Eliminate unnecessary hot plates, coffee pots, and other small appliances.
Turn off all tools, office machines, and portable appliances when not in use. If you are the last one out for the day, turn off photocopiers and other equipment.
Less frequently used equipment with remote controls such as televisions and VRCs should be unplugged when not in use, because they use power even when not being operated.

Energy savings estimate for one copy machine: 5 amps x 120 V x 30% efficiency X 15 hours x 5 days x 52 weeks = 702 kW or $35 per year savings (based on $0.05 per kWh). Calculations were received from data provided by Idaho Power publication ESD-263.

Vending machines

Governor Kempthorne's Executive Order calls for lights in vending machines to be disabled to conserve energy. Inside office buildings that are otherwise well lit, lighted panels on the front of soda machines is an unnecessary use of electricity. If needed, signs can be placed on the machines indicating that they are, in fact, operational. However, experience in other state has shown that this is often not necessary.

The Vending Miser is a device that monitors activity around a vending machine and regulates it's cooling schedule to optimize energy efficiency. The device, manufactured by Optimum Energy Products, has been tested by both Coca-Cola and Pepsi Corporations and found to be acceptable for use in their machines (see www.optimumenergy.com/management/miser.html#vending). An independent study by Foster-Miller Research found the device to provide adequately-cooled beverages and possible increased life of vending machine compressor and fan mechanisms.

In the Division of Public Works, we conducted an informal test* of one of the vending miser devices on a soda machine in the building. The machine is located in a low-traffic area beneath a stairwell at the basement level. A line logger (a device that measures kilowatt-hours of energy consumed by an electrical device) was attached to the vending machine. Over the course of one week, the logger recorded the amount of energy consumed by the machine during normal use. For a second week, a vending miser was attached to the machine. The difference in electricity consumed was surprising:

Weekly consumption without miser	49.3 kWh
Weekly consumption with miser	19.0 kWh
Difference of consumption	30.3 kWh
Energy savings for one year	1576.6 kWh
Cost savings per year: 0.03/kWh	$47.30
Cost savings per year: 0.04/kWh	$63.10
Cost savings per year: 0.05/kWh	$78.80

* This informal test was unscientific, and is not meant to provide precise data about the function of the vending miser device, nor to suggest or substantiate any claims about the device. The informal test was conducted purely in the spirit of curiosity, and should be read with that spirit in mind.

For more information regarding this page, please email the Facilities Management or call 208.332.1900.