The SunEdison LLC solar farm doesn't "wake up" every day with a rooster or even a playing of the Beatles' "Here Comes the Sun."
Instead, GPS software tells the 63,000 photovoltaic solar panels on mounted solar-tracking towers that it's time to go to work collecting particles of light called photons.
Every day since being switched on in late December, the towers have tilted slowly like sunflowers to do their part to provide energy to about 2,600 homes — most likely in North Carolina, though there's no precise way to determine where the electricity flows once it reaches the power grid.
The towers — which replaced rows of corn and tobacco — are precisely placed, not just for the inspiring, rolling symmetry at the Golden Crescent Farms site off New Jersey Church Road in Linwood.
It's necessary to keep the shadow of one tower from covering another because "shade is like poison to the panels," SunEdison employee Greg Cunningham said.
It's been Cunningham's job the past 18 months to set up the more than 200-acre facility — the largest solar farm in North Carolina — to meet the requirements of Duke Energy Corp. The farm is surrounded by fencing topped with barbed wire to keep out trespassers and vandals.
"The panels try to get what they can first thing in the morning," Cunningham said. "They are their most productive between 9:30 a.m. and 3 p.m., then they try to get what's left of the day."
Cunningham said he and the two companies breathed a major sigh of relief last March when the solar farm was spared as a tornado plowed through Davidson County about 7 miles west of the farm. At least four mobile homes were squashed in Chestnut Grove Mobile Home Park off Clark Road near Interstate 85.
Cunningham said the towers are programmed to go flat if a 50-mph wind blows through for more than a minute. Once the wind subsides, the towers reactivate after 45 minutes.
"There's not much else you can do when you hear about a tornado warning except cross your fingers," Cunningham said.
As big as it is, the 17.2-megawatt solar farm pales in comparison to a 70-megawatt facility SunEdison built in Italy last year and sold for $364.7 million.
What made the Linwood site attractive to SunEdison and Duke was the wide-open space in three parcels so far, limited landscaping and topography changes, close access to a row of high-voltage power lines and — surprisingly — the moderate climate.
Although many solar farms are in desert settings, the intense heat and the sand-blown conditions at times can make the panels less efficient than they are on a cloudless 60-degree day in Linwood.
"Extreme heat can lower the efficiency of the panels," said James McLawhorn, the director of public staff for the N.C. Utilities Commission. "The hotter it is, the less electricity it can carry."
Still, the world's largest solar power plant is in the Mojave Desert, which has 1,000 acres of solar reflectors. About 90 percent of the world's commercially produced solar power comes from that plant.
* * * * *The impetus for the Linwood solar farm and other efforts in North Carolina comes from the Renewable Energy and Energy Efficiency Portfolio Standard.
It requires public utilities to have the equivalent of 3 percent of their retail sales come from renewable energy and energy-efficient sources by 2012. That jumps to 6 percent in 2015, 10 percent in 2017 and 12.5 percent in 2021.
Duke Energy has signed agreements with SunEdison to buy the entire output of the $137 million Linwood solar farm for 20 years.
"Solar energy continues to increase in its importance to North Carolina customers," said Brett Carter, president of Duke Energy N.C. "Partnerships like the one with SunEdison have allowed Duke Energy to comply with North Carolina's solar requirements in a cost-effective way."
Apart from the Linwood plant, Duke is installing solar panels on office buildings, manufacturing plants, schools and warehouses to create about a 10-megawatt generation network in the state. It has a 1-megawatt facility in Shelby.
A Charlotte group, O2energies, is trying to secure financing from regional banks for a 1.15-megawatt solar farm in Mount Airy on city-owned property near the wastewater-treatment plant. The city has approved a lease for the 6-acre site.
Joel Olsen, the managing director of O2energies, said initial site work is under way with the goal of the "multimillion-dollar" farm being completed in the second quarter.
Nearby Pike Energy Solutions is serving as the main contractor for a project that is expected to require more than 20 subcontractors and more than 200 workers. Surry Community College is providing solar-technology training.
The project, nicknamed Mayberry Solar, will generate about 1.6 million kilowatt-hours into the Duke grid — enough to serve about 200 homes.
"The solar electricity will flow through the grid to local residences and businesses that require electricity at the time it is being generated," Olsen said. "This clean energy will offset the area's need for electricity generated by the 50-year-old coal plants that serve the Mount Airy region."
* * * * *Olsen said smaller solar-power plants tend to be more efficient by being close to the point of consumption, minimizing the loss between generation and consumption.
"Solar also does not need a large water reservoir for cooling," he said. "The largest consumer of surface water in our state is our large, centralized power plants, which use millions upon millions of gallons of water each year.
"As the water wars between North and South Carolina continue to increase, solar will become an increasingly viable source of electricity generation."
Other solar-energy projects in North Carolina include Progress Energy's initiative for facilities producing a combined 11 megawatts, the largest being the Sutton Plant in Wilmington.
EnergyUnited has a solar farm in Taylorsville that is producing enough energy for 150 households.
Robert Reichenberger, the U.S. vice president of utilities for SunEdison, said North Carolina "is a great market for solar energy and solar farms. We're just reliant on utilities' appetites for what we produce."
Even companies such as SAS in Cary have jumped on the solar-energy trend. In October, it opened its second solar farm on its headquarters campus.
Progress Energy is purchasing the electricity generated from the 1.2-megawatt and 1-megawatt farms. Combined, they produce energy to power 325 homes.
"Projects like our solar farm demonstrate a fundamental shift in the value placed on energy efficiency, intelligent power sourcing and end-user consumption," said Jerry Williams, the environmental sustainability program manager for SAS.
"The development and implementation of alternative sources of energy is important for our environment, a stimulus for our economy and a step in the right direction to achieving energy independence."
Olsen said the initial solar projects are creating work force experience in the state.
"But we need a long-term strategy to develop a larger market for solar in North Carolina in order to create the jobs, investment and industry supply chain here rather than in California," he said.
McLawhorn of the utilities commission said the Linwood solar farm will likely serve as a template for future solar-energy projects.
Although there is a "low probability" that there will be a solar farm the size of Linwood in the near term, he said that as demand for solar energy increases, there will be more incentive for joint ventures.
rcraver@wsjournal.com
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