Power monitors benefit homebuyers and builders selling energy efficiency.
Reviewing a phone bill can be a little daunting. Each bill usually contains several pages detailing the exact breakdown of your charges. By comparison, electric bills seem relatively streamlined. They have a simple equation of the number of kilowatt-hours multiplied by the current rate, with a couple of extra fees and adjustments added.
Although it's quick to read, it's not very informative. It doesn't tell you how much your refrigerator cost to run last month, or how much money you're saving by doing laundry at night. You may hope that your new, efficient dishwasher is offsetting the cost of operating your home-theater system, but there's no way to tell.
Consumers have traditionally accepted having little control over evaluating their energy usage, but increasing utility bills and improved awareness of energy-efficient building products and appliances have amplified consumer demand for more information about and control over their energy usage. By wiring a home with an energy monitor, builders provide homeowners with a tool for understanding and controlling their home's energy consumption. Detailed information about how their homes use energy allows homeowners to evaluate their appliances and other electrical devices, as well as their own habits, and to make changes accordingly.
New Twist, Old Concept
The concept of home energy monitoring is not new. Plug-in devices that measure an individual appliance's energy usage and efficiency have been available for several years. For example, the Brand Electronics line of digital power meters can be used to identify large electricity loads, measure intermittent loads for appliances such as refrigerators and air conditioners, or help diagnose equipment problems. Information can also be downloaded from the unit to a PC to allow consumers to see and analyze their energy time-of-use.
Smart home technology is enabling the next generation of advanced power monitors to provide an even broader range of information to the user. Italy's largest electricity distribution company recently began installing digital energy meters that provide its residential customers with several useful points of information. The meters not only check the total energy consumption and the consumption of individual appliances, but will also allow consumers to take advantage of time-of-use tariffs or real-time tariffs, to compare energy usage with previous months, and to receive guidance on how to save energy.
Whirlpool's new Home Energy Monitor, which is currently being evaluated in several homes, is taking the technology a step further. The monitor is installed as part of the home circuit panel and transfers data to a PC or touchpanel. In addition to charts that show current energy consumption by appliance and room, the device creates a log that demonstrates how energy usage changes by the hour. The monitor also shows homeowners the most economical time of day to use their appliances.
"The technology took on a life of its own," says Gale Horst, lead engineer of advanced electronics applications at Whirlpool Corporation. The idea originated from Whirlpool research that indicated that consumers wanted to better understand how their appliances use energy and how to minimize their energy consumption.
"It's like an energy dashboard," says Horst, who explains that the monitor provides consumers with a tool for understanding how their home operates. "Consumers want to leave a light on when they leave the house. Now they know which light to leave on."
Builders' Benefit
Home monitoring devices also provide a useful tool for builders, according to Joe Wiehagen of the National Association of Home Builders (NAHB) Research Center in Upper Marlboro, Md. "Builders who have committed themselves to energy-efficient building often find that communicating the value of energy efficiency to the customer is a difficult task," says Wiehagen. "This type of technology can help communicate that value."
Wiehagen adds that this type of information technology can help builders guarantee energy bills and can help assure homeowners that their home is operating properly.
Joe Wiehagen is senior project engineer for NAHB Research Center. Visit www.nahb.org.