Utility's 'Voltage Reduction' Plan Saves Energy
RENEE MONTAGNE, host:
In Washington State, a mid-sized public utility is helping consumers get more life out of their light bulbs and other appliances. It's a side benefit to an effort by the Snohomish County Public Utility to save millions of dollars and conserve energy. The utility's approach is based on conservation voltage reduction. NPR's Wendy Kaufman explains.
WENDY KAUFMAN reporting:
Think of voltage as electrical water pressure. U.S. utilities are required to deliver that pressure at 120 volts, plus or minus five percent, or between 126 and 114. How much voltage is actually delivered to your house depends on a number of factors. But a big one, says Mike Sheehan of the voltage regulation startup firm MicroPlanet, is how close you are to a power distribution station. Like this one, in suburban Seattle.
Mr. MIKE SHEEHAN (Vice President of Business Development, MicroPlanet): Right here is the substation, and if you looked at a circle real close within the first half mile of the substation you'd be running very, very high. All those customers would be running at the high end of the scale, 125 volts. Then as you get a mile out, they'll be running like 124 volts.
KAUFMAN: As you get farther and farther away, the voltage will continue to drop. So, electrical utilities typically send out more voltage than many customers need, to ensure that the house at the very end of the distribution line gets enough.
The Snohomish County Public Utility rejects that approach, saying it can cut voltage and still be well within the range for providing safe and reliable service.
Led by its voltage reduction crusader, Robert Fletcher, the Seattle area utility has reduced the voltage it sends out to an average of 117--a cut of 2.5 percent.
Mr. ROBERT FLETHER (Snohomish County Public Utility): And, two and a half percent buys the average customer about 350 to 400 kilowatt hours per year savings. So, the net savings for our 300,000 customers is about three and half million dollars a year.
KAUFMAN: That, he says, translates to money the utility doesn't have to spend buying and transmitting power. And it means less energy is consumed.
Citing a study by the electric power research institute, Fletcher says there's another advantage to lower voltage. Some appliances and incandescent light bulbs would last longer, though the bulbs wouldn't be quite as bright.
The utilities are quick to point out the potential hazards in lowering voltage too much. Jim Owen is a spokesman for the Edison Electric Institute, a trade association. He suggests what could happen if the utility is feeding electricity at 117 volts, and the demand suddenly increases, or something goes awry on the system.
Mr. JIM OWEN (Spokesman, Edison Electric Institute): You might be faced with a situation in which you're moving from 117 pretty quickly down to 112, 111, something of that nature. And when you get into a situation like that, you might find yourself with appliances or machinery that could malfunction, or possibly even be damaged.
KAUFMAN: Snohomish officials say their sophisticated monitoring system could adjust voltage levels and prevent that.
The Northwest Energy Efficiency Alliance, an organization supported by utilities, state governments, public interest groups, and others, is currently evaluating the Snohomish model and its applicability across a four-state region. The Alliance's Executive Director, Margaret Gardner, believes the model will prove viable. And, she says, that while voltage reduction is just a tiny piece of the energy efficiency and conservation puzzle, it is worthwhile.
Ms. MARGARET GARDNER (Executive Director, Northwest Energy Efficiency Alliance): It's an excellent thing, because not only do you save some money for consumers, but you avoid building one or two combustion turbans.
KAUFMAN: Even with the advances in technology that make voltage reduction and sophisticated monitoring possible, there are significant challenges to implementing it broadly. Among them, utilities have long been skeptical, even fearful, of changing the system in a way that might mean inadequate electricity to their customer. And, says Gardner, investor-owned utilities have been wary about cutting revenue.
Ms. GARDENER: When you lower the voltage, you do lower your kilowatt hour sales, and sometimes utilities would like to keep the voltage high in order to make sure they get revenue for their shareholders.
KAUFMAN: But Jim Owen, of the Edison Electric Institute, dismisses the idea that investor-owned utilities are ignoring conservation measures for the sake of profit. He says that over the past fifteen years, utility efficiency programs have helped customers save about 700 billion kilowatt hours of electricity.
Wendy Kaufman, NPR News, Seattle.
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