RALEIGH -- Hydroelectric power, a tiny component of North Carolina's energy grid, is getting another look in the Triangle as a state mandate to increase the use of electricity from renewable resources draws near.
A small hydroelectric plant built at Jordan Lake's dam by Hydro Matrix, a Tennessee company, is expected to begin generating power for about 1,700 homes as early as next summer.
Meanwhile, a Vermont company is considering whether to sink a set of six turbines into the bottom of Falls Lake to harness energy from moving water at the reservoir's dam. If approved, a process that could take several years, the system could provide power for as many as 1,200 homes, said Lori Barg, head of Community Hydro of Plainfield, Vt.
Progress Energy would buy the energy from both projects.
"Water's going to fall, and if you can get renewable power by water that's always falling, why not?" Barg said. "It makes sense to use water and gravity, and Falls Lake is a dam that's been there and isn't going to be removed."
In 2007, the state legislature required power companies to derive at least 12.5 percent of their energy from a combination of renewable sources and from energy-saving programs by 2021.
Both Progress Energy and Duke Energy, the two major energy companies in the state, get less than 1 percent of their power from renewable energy sources such as solar, wind or biomass. Only new hydroelectric projects, rather than the existing dams in the Piedmont, would count toward the state's 12.5 percent goal for renewable sources.
Most of North Carolina's power comes from coal and nuclear reactors; current hydroelectric sources are mostly in the Piedmont and western part of the state.
The utility companies will have to cobble together energy from small sources such as the hydroelectric ones as well as solar and wind projects, several of which are expected to be rolled out in coming years, said James McLawhorn, who handles electricity issues for a state agency that represents consumers before the N.C. Utilities Commission.
"We're on track,"McLawhorn said. "Whether we're actually going to hit the percentage, we don't know that for sure."
But in setting the goal for renewables, the legislature capped the amount utilities could spend developing renewable resources at $1.5 billion by 2021, making it more difficult. The extra cost of renewable energy, which is generally more expensive than coal or nuclear-generated power, is passed on to consumers who pay a monthly fee approved by the commission. Progress Energy consumers now pay $0.36 a month, while Duke Power customers pay $0.16 a month, for renewable energy.
As the companies start incorporating more energy from renewables, that cost will go up, McLawhorn said, but won't exceed $10 a year per customer.
Raleigh has questions
The proposal by Community Hydro to consider building a small hydroelectric plant on Falls Lake dam caught the Raleigh City Council by surprise this week when city staff members disclosed it at Wednesday's council meeting.
Falls Lake provides drinking water for Raleigh and several Wake County communities.
"It would make a lot of sense for the entity to come and talk to the city since it affects our drinking water supply," Mayor Charles Meeker said. "We want to find out what it means and whether it could adversely affect the water supply."
The N.C. Wildlife Resource Commission wants to ensure that fish populations in Falls Lake and the Neuse River are protected. The U.S. Army Corps of Engineers, which oversees Falls Lake dam and the reservoir, knew about the proposal earlier this year. Allen Piner, a hydrologic engineer for the Corps, said other companies have looked into harnessing electricity at the dam before, but didn't move forward because of the cost.
Hydro Matrix, the company now assembling the hydroelectric plant for Jordan Lake at an off-site location, looked at Falls for several years but decided not to pursue a project there because of the cost, said Jim Price, the company president.
Barg of Community Hydro said the technology her company would use wouldn't affect the lake's water quality or the flow of water in and around the lake. Large-scale hydroelectric plants often need certain volumes of water to maintain operations.
She said the company's turbines, each about the size of a 55-gallon drum, can be removed if the lake faces a chance of flooding, as it did when Hurricanes Fran and Floyd hit the state.
Aliessa Bierma, the Upper Neuse Riverkeeper employed by a nonprofit foundation that monitors the river, said that in these initial stages the project seems like a smart way to get energy from the lake.
"I am wholeheartedly against any new dams on my river," Bierma said. "But it could be a very innovative way of getting power from things we already experience."
