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Gadgets to Spur Energy Conservation

When the box turns red, it’s time to turn off the air conditioner and save electricity.
November 14, 2007

Can glorified glow lamps stop blackouts and slash energy costs? Manhattan-based ConsumerPowerline thinks so. This winter, about a thousand participants in the company’s energy-conservation program will receive small plug-in boxes that glow red when power demand peaks, urging them to turn off space heaters, defer dishwasher runs, or otherwise save electricity.

Red alert: The red glow of the Joule meter from ConsumerPowerline and Ambient Devices tells participants in an energy-conservation program that their local power grid is jammed and that their utility will pay them to power down. Data sent to the device over a satellite pager network includes regional power costs and consumption (indicated by the bars at the left and right) and the local weather and temperature.

Energy suppliers respond to spikes in demand by gearing up extra production capacity. That can be so expensive that many utilities are willing to pay to promote conservation during periods of peak use. ConsumerPowerline pays apartment complexes, companies, and institutions to conserve on cue, then resells the resulting “negawatts”–reduction in demand–to utilities in New York, Massachusetts, and California.

Currently, ConsumerPowerline requests negawatts from its participants by paging them or sending them faxes, e-mails, or voice mails. This month, however, the firm received its first shipment of digital gauges, each about the size of an air freshener, that download information over a low-bandwidth satellite pager network. In the coming weeks, the company will distribute the gauges to participants in its program and, in some cases, display them in public spaces. Humphrey Wong, ConsumerPowerline’s manager of incentive innovations, hopes that the devices will lead to an additional 5 to 10 percent drop in power consumption among organizations that already deliver reductions of 15 percent or more.

“We’re trying to provide a relatively inexpensive tool for people to be informed about when to make good energy decisions,” Wong says. That tool, the Joule, was developed jointly by ConsumerPowerline and MIT Media Lab spinoff Ambient Devices, based in Cambridge, MA.

When a utility schedules what’s called in the business a “demand response event,” Ambient signals the appropriate Joules to turn from green to blue and to display a countdown to the time at which the utility wants negawatts. Two hours before the event, the blue light begins to pulse. Finally, the Joule glows red to signal the start of the event, and it displays a new countdown that lets the user know when the event will end.

Wong hopes that, in addition to increasing conservation among current participants in ConsumerPowerline’s program, streamlined communications will enable the company to reach out to individual homeowners–a largely untapped market–thereby multiplying its capacity to deliver negawatts.

The Joule isn’t Ambient Devices’ first foray into demand response. Since 2004, major California utilities have been testing Ambient’s Energy Orb, a glass sphere that changes color to indicate the state of the grid. One utility, Pacific Gas and Electric, adopted the Orb as a commercial product last year, distributing 2,000 Orbs to customers who have agreed to supply negawatts. Like all of Ambient’s products, the Orb receives its instructions over the pager network.

Ambient is also testing a new signaling device with EnBW, Germany’s third-largest utility. Because energy prices in Germany vary by the hour, the new device will receive even more information than the Joule will. Its three-inch-square LCD screen is large enough to display crude graphs of hour-by-hour pricing for the next 24 hours as well as a forecast of the following day’s energy prices and weather.

Most U.S. utilities are currently piloting time-specific pricing schemes like the one in Germany, and Wong hopes that this will create a new market for the Joule: helping residential and small commercial consumers track price shifts. Many utilities are planning to break their residential rates into just a few categories–a level of complexity the Joule could handle. Southern California Edison (SCE), for example, plans just three pricing categories: off peak, regular peak, and critical peak (the latter likely limited to the hottest summer afternoons, when the grid is most at risk).

Wong says that on such days, the Joule could make a major difference. “If one home turns off their air conditioner, that’s one kilowatt. But if you get 1,000 homes, all of a sudden you’re talking about one megawatt.”

Ambient and ConsumerPowerline, however, will soon face competition thanks to new utility-installed meters that will use the cellular-telephone network and Wi-Fi, rather than satellites, to relay pricing information. SCE’s $1.7 billion SmartConnect program, for example, aims to install smart meters in five million southern California homes and businesses between 2009 and 2012.

Paul De Martini, who directs the SmartConnect program, says that the meters will communicate with the utility via the cellular network, then broadcast pricing and local power-consumption information to home networks, probably using a low-power form of Wi-Fi called ZigBee. De Martini says that at least 20 companies, including giants such as General Electric, are developing ZigBee-enabled devices to pick up, interpret, and display that information. De Martini’s team at SCE has assembled a device of its own: a battery-powered ZigBee refrigerator magnet with green, orange, and red LEDs that represent off-peak, normal-peak, and critical-peak pricing. A commercial version of such a device could be cheap enough to give away.

De Martini thinks that an even more effective means of encouraging conservation will be devices that display household power consumption in real time. “The thing that really works well for people is when they can see it dynamically, kind of like when you’re at the gas pump and you can see how much it’s costing you as the dial clicks around,” he says. That dynamic view, he predicts, will not only shift consumption from peak to off peak, but it will actually reduce total power consumption.

Ambient and ConsumerPowerline may survive by incorporating ZigBee into their own devices. But Wong says that his company won’t make that move unless this winter’s pilot test proves that the Joule display motivates enough negawatts. “We know there will be a behavioral response,” he says, “but we need to understand the full value of that behavioral response.”

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