At first glance, the thousands of glimmering panels erected on a former farm in southwest Davidson County seem like a brigade of energy soldiers, poised to vanquish America's environmental bugaboos.
But construction manager Greg Cunnington knows the pollution-free electricity that Maryland-based SunEdison generates from the 64,000-panel solar array will be just a drop in the bucket compared with the state's total energy use.
"If you don't put any drops in the bucket," Cunnington said, "then you never have a chance of getting it filled up."
The construction scene where Cunnington works looks like any other, full of hard hats, forklifts and dusty utility vehicles, except the workers won't leave behind the typical industrial park or subdivision when they finish. Steel columns hold rows of rotating blue and silver panels that track the sun's movement from east to west.
The cells in the panels will absorb sunlight and convert it into direct-current electricity, which a device then will convert into the more practical alternating-current electricity. A Duke Energy substation near the farm will change the voltage of the AC power before distributing it through power lines to homes and businesses.
The company began construction in July and expects to start generating about 3.5 megawatts of usable power by year's end. The operation should power more than 2,600 homes .
"It's like nothing I've ever done before," said Karli Christman , an assistant project manager from High Point. "It's a great opportunity to be part of a green project."
Meeting state targets
Duke Energy will purchase the output — a planned 16 megawatts of the roughly 20 megawatts generated — over a 20-year period as part of its goal to meet the state's interim and long-term renewable energy requirements. The utility provider needs to sell 12,000 megawatt-hours of solar energy per year by 2010 and 10 times that amount by 2018 .
That solar mandate covers fewer than 1 percent of the 8 million megawatt-hours of renewable-based electricity Duke needs to sell by 2021 . And all of this must cost residential customers no more than $10 to $34 more per year.
The company believes it can meet its near-term goals without hitting cost caps, said Owen Smith , managing director of regulated renewable energy and carbon strategy . Among other things, Duke plans to spend $50 million building mini solar farms on the rooftops of buildings in Greensboro and other cities. It also will purchase credits for the energy generated by two North Carolina companies that build solar heating and cooling systems.
"There's a lot we need to do between now and then," Smith said about meeting the goal. "There's a lot we don't know about what renewable resources will cost."
Despite its modest contribution to our energy needs, renewable energy will have a substantial effect on utilities' management practices and North Carolinians' sense of control about their energy future.
Residents and business owners will see more, and possibly get paid for operating, solar arrays atop roofs, near parking lots, on farmland and in their neighborhoods. Duke estimates that it could oversee 750 renewable energy projects throughout the state by 2021 , compared with the 17 conventional power plants it's managed in the past, Smith said.
Solar is clean but costly
Installation costs — not lack of availability — are the biggest obstacle to solar energy meeting a larger portion of the country's energy needs . Component prices have steadily declined over the years, but large, grid-connected systems can cost 28 to 42 cents per kilowatt-hour versus 5 to 10 cents for natural gas power plants and 9 to 12 cents for wind turbines, according to the Pew Center on Global Climate Change .
Still, solar's flexibility — it can go anywhere the sun is shining — and its ability to harvest the planet's largest renewable resource keep it high on the list of ways to reduce pollution and greenhouse gas emissions. Even after initial enthusiasm for solar energy waned in the late 20th century, firms continued to research and install panels across the country.
Now, the U.S. has at least 8,800 megawatts of installed solar heating and electrical capacity, with more than 18,000 individual photovoltaic systems going up in 2008, according to the Solar Energy Industries Association.
Helping the industry were long-standing tax credits and groups such as N.C. GreenPower, a 6-year-old nonprofit that offsets system costs for home and business owners who sell their renewable energy to utilities. The group contracts with almost 300 solar electricity generators, including Leon's Beauty School , which installed a 165-panel rooftop array in October as part of its efforts to adopt green practices.
"I'm doing this for my grandchildren," said Parker Washburn , owner of the Greensboro school. "When you finally have grandkids, you want to change your legacy."
State renewable energy quotas created openings for utility-scale projects, and SunEdison rode North Carolina's policy wave into the Piedmont, purchasing a 356-acre farm on New Jersey Church Road in Davidson County and promising to invest $173 million on a massive array that, at the time, would have been the largest in the country. The company also sells or plans to sell output from a 1.2-megawatt operation in Wilmington to Progress Energy and a 1-megawatt array in Alexander County to EnergyUnited Electric Membership Corp. in Statesville .
The solar farm carries modest economic benefits for Davidson County, at least in the short term. SunEdison, sold to a larger company in October, will employ about 80 people during construction and three permanent workers. The county will receive $7,800 more per year in land-related taxes, but SunEdison will pay only 20 percent of the system's appraised value, thanks to a state tax incentive.
Still, county leaders believe the project's greatest promise is its potential to draw other green industry; County Commissioner Larry Potts noted that "the PR far exceeds the job creation."
Can solar stand alone?
Tax breaks and policies can take the solar industry only so far, especially if the economy stays weak and federal lawmakers don't pass a climate bill limiting carbon emissions. The assistance gives companies and researchers time to bring their costs down, so the technology can eventually stand on its own, said Mark Preston , chief operating officer for MegaWatt Solar in Hillsborough .
"Nobody in this industry believes it's viable unless we're able to be competitive without those subsidies," Preston said.
MegaWatt Solar designed a photovoltaic system with the potential to cut costs by up to 30 percent and generate significant job growth in North Carolina. The company wants to build large-scale systems for utilities and it sells output from one pilot project in Caswell County to the 31,000-member Piedmont Electric Membership Corp.
"Not only does it look good, but it's a new technology that optimizes the rays from the sun and reduces the use of silicon," said Susan Cashion , the cooperative's manager of public relations .
The "solar trees" use readily available components, including mirrors, precast concrete pads, aluminum frames and circuit boards, and only 5 percent of the system's cost comes from imported solar cells, Preston said.
"Because the things we are using are simpler and more conventional technologies and we don't need an investor to spend millions developing something, that means we can have a lot of local suppliers who can do these things easily," he said.
Contact Morgan Josey Glover at 373-7078 or morgan.josey@news-record.com
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