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GridWise trial finds 'smart grids' cut electricity bills

Department of Energy study finds consumers are willing to have their appliances remotely controlled by utilities to save them money and offset more grid build-out.

Results from a year-long study on high-tech electricity meters found smart grid technology performed as intended, saving consumers about 10 percent on their bills while easing strain on the power grid.

The Department of Energy's Pacific Northwest Laboratory on Wednesday released the findings from its GridWise project, which tested the use of Internet-connected thermostats and other controls in 112 homes in the Seattle area.

Consumers also tried out appliances, like water heaters and dryers, that were able to automatically change their settings according to signals sent by the utility over the power grid.

The trial showed that consumers are willing to have utilities remotely dial down the appliances to lessen the load on the power grid and reduce their consumption, said Rob Pratt, program manager at Pacific Northwest National Lab.

These changes could be as small as turning off the heat on the dryer while it continues to tumble for a few minutes. But those minute-to-minute adjustments, driven by the fluctuating demand on the power grid, can have significant benefits to utilities.

"We could save $70 billion in investments in the next 20 years by offsetting construction of new infrastructure that would otherwise be needed to meet load growth," Pratt said during a teleconference with the media.

Smart grid technology would also provide more reliability to the power grid, allowing utilities to isolate problems more easily. Clean power sources such as wind and solar, which pose technical challenges because they don't supply a steady stream of electricity, can be better incorporated with upgraded equipment, the study found.

The electricity infrastructure in the United States needs significant investment to be modernized, according to industry analysts. But utilities tend to be very conservative and unwilling to make large capital expenditures on new equipment.

"The only thing that will move this forward is simply the fact that we have got to do something," Pratt said. "(Utilities) have been delaying investment (in physical infrastructure) and they're going to need computer and Internet technologies as a stopgap if nothing else."

The recently passed energy bill includes a title that would allocate additional research for smart grid technologies. It also outlined a process for standardizing communications protocols.

LED display
Participants in the study said that the technology used in the field test is already available. IBM was the systems integrator in the project to provide the back-end software that communicated information between utilities and consumers.

Homeowners in the study were equipped with a gateway device that used an existing broadband Internet connection to receive pricing information from the utility, which is transmitted wirelessly to a smart thermostat and a smart meter.

Consumers had the ability to preset certain conditions, allowing the utility to lower the thermostat, for example. They could manually override those settings and go online and see how prices fluctuated in real time.

Participants were able to choose on a sliding scale between economy and comfort. The thermostat had an LED display to indicate when the utility was automatically controlling appliances.

One consumer in the study said that he relied almost exclusively on pre-set levels and automatic changes, except for a few occasions where the temperature in the home dropped more than the people in his household was willing to accept.

"Ninety-nine percent of the time, we accepted what the system was offering us," said Jerry Brous, a 67-year-old Seattle-area homeowner. "You learn how much you will tolerate."

One of Brous' favorite features was the ability to control his house's climate remotely over any Internet connection, allowing him to turn on the hot water heater or heat before returning from a trip.

Despite their effectiveness, one of the persistent problems with smart grid technologies is that they requires additional investment on the part of utilities and, potentially, consumers.

Pratt said that the smart grid technology used in the study costs about $1,000 per home, but it could be as little as $400 or $500. Average savings from energy efficiency for a utility in a deployment would be in the 5 to 15 percent range.

He predicted that there will be extensive use of these technologies in different areas within 5 years, and that in 10 to 15 years there will be "big waves of integrating customers."

"The key issues are not technical and much more regulatory. We're fundamentally displacing the need for new infrastructure," he said.