Water vapor rises from scrubber towers at the Progress Energy Lake Julian power plant. Photo: Courtesy of Progress Energy

Electricity is like tap water, so taken for granted that most of us are aware of it only when it’s not there.

by Michael Hopping

But the invisibility of reliable power has a downside. When there’s a problem behind the scenes, power companies can have a hard time getting our attention. In Asheville and surrounding areas this is one of those times.

On cold winter mornings we use more electricity than the 867 megawatts (MW) Progress Energy is able to produce locally. That was already the case almost three years ago when public opposition and the Woodfin Planning and Zoning Board shot down the company’s plan to build a new peak power plant in Woodfin.

Since then the gap between homegrown generation and consumption has widened dramatically. On the morning of January 16, 2009, peak demand exceeded 1050 MW, a number Progress didn’t expect until about 2015.

For now, Progress is able to import the needed power — bought at premium prices — from outside the area. The contracts expire in three years and may be extended for one more. After that, who knows?

Supply and Demand

The 20th-century answer to problems like this was simple: build a new fossil fuel power plant. That’s what Progress tried to push through at Woodfin. But global warming and a host of other factors are forcing a rethinking of this historic solution.

It can’t go on being about selling ever more electricity produced from coal or other fossil fuels. Nuclear power is scary expensive, even apart from debates about radiation, spent fuel, etc. Alternative power sources cost less, but sun and wind aren’t a total answer either. Power dispatchers in Raleigh can’t turn on the sun or make the wind blow on demand.

At the moment, the network of power plants and transmission lines we know as “the grid” has very little capacity to store power for later use. There aren’t any giant batteries to call on. Voltage has to be regulated minute by minute by dispatchers who turn generating stations on or off to balance the amount of electricity customers are using. If there’s too much juice, equipment may get toasted; too little and the lights go dim.
Demand Side Management

Instead of balancing the energy equation only by changing the supply side, why not also influence demand? Our problem, for example, is jumps in the amount of electricity consumed on frigid mornings when people are getting up and businesses are preparing to open. These demand spikes, also known as peak demand, are handled by feeding more power into the lines. But it’s also possible to blunt spikes by turning some things off.

There’s truth in the saying that “the cheapest watt is the one you don’t use.” Progress cut the power bill in its own WNC facilities last year by an average of 20.8% by doing things as simple as turning off lights and closing bay doors when not in use. Residential customers are charged 9.634-10.634 cents per kilowatt hour, depending on the month. The cost of energy efficiency programs averages 2-3 cents per kilowatt saved, measured over the lifetime of the improvements.

Better insulation, Energy Star appliances, compact fluorescent lightbulbs and several other efficiency measures reduce electric consumption across the board, not only at times of peak demand. State and federal tax credits along with new incentives from Progress encourage efficiency upgrades.

The company’s EnergyWise program specifically targets demand spikes. Residential customers are paid to allow Progress to cycle electric heat, hot water, and air conditioning systems off and on at times of peak demand. This “demand side management” is an early step toward the interactive electric grid of tomorrow. Planners hope one day to have all parts of it — from traditional power stations and wind farms to household appliances — talking to each other and working together. 

The Alternative to a New Power Plant

The amount of electricity saved by Progress incentive programs depends on customer participation. More broadly, unless WNC residents reduce demand spikes by 20-25% (200-250 MW) within the next few years, Progress is highly likely to propose another peaking power plant in someone’s neighborhood.

Are savings of this magnitude reasonable? Yes. The average North Carolinian uses twice as much electricity as an average Californian. That’s overall use, not peak demand. Reducing peak demand is easier. Running the clothes dryer during off-peak hours cuts peak demand but has no effect on total power use.

Progress officials from CEO Lloyd Yates on down insist that they’d rather not build another plant. Following the Woodfin defeat, Progress selected a group of local leaders to advise it on how to promote energy efficiency and conservation. The Community Energy Advisory Council (CEAC) has met regularly since then. While the group has much to be proud of, reductions in peak demand are not among them. WNC is almost 100 MW deeper in the hole now than when the council was formed. Sam Waters, Progress Energy’s Director of System Planning, attributed the increase to population growth and higher per capita use.

CEAC isn’t the only game in town. Ned Doyle, coordinator of the Southern Energy and Environment Expo (this year’s expo takes place on August 21-23 at the WNC Agricultural Center), is launching “250 MegaWatts of Community Action.” Progress has partnered with Doyle on the project, which intends to engage the community in reducing electricity consumption by 250 megawatts. For details on this and Progress Energy’s efficiency programs see www.seeexpo.com/about/250megawatts.htm .