WALTERBORO, S.C. – In its first year of operation, the Colleton Solar Farm produced slightly more solar 
power than expected and demonstrated the benefits of panels that track the sun, even though they cost more than stationary panels. Also, the severity of Winter Storm Pax last February highlighted the issue of the reliability of solar power to meet winter energy demands after the storm took the farm offline for three days.
The first full day of operation for the Colleton Solar Farm was December 21, 2013. In its first year, through December 20, 2014, the 15-acre site generated 4,687 megawatt-hours (MWh), which was 5 percent more than expected in year one. That extra energy is enough to power more than 1,200 light bulbs (60 watts) for eight hours a day. All told, the 3-megawatt complex provides enough energy to power more than 300 homes.
Data also indicates that tracking panels that follow the sun generate power for about 3 ½ hours longer than the fixed panels during the longest days of summer. Nearly two hours of that time is electricity delivered during the afternoon peak of power demand.
TIG Sun Energy, under contract with Santee Cooper, owns and operates the Colleton Solar Farm. Santee Cooper is purchasing the solar output in collaboration with Central Electric Power Cooperative and the state’s electric cooperatives. Dedicated January 24, 2014, the solar farm was planned as an energy source and also as a resource for studying data on costs, performance and integration of utility-scale solar power into a sophisticated electric grid.
“Through this first year, performance from the Colleton Solar Farm has been consistent with expectations, which has validated the project and highlighted the intermittency of the resource. Solar power is only available when the sun is shining, and there are times when that helps South Carolina electric consumers and times when other energy sources must be utilized instead,” said Marc Tye, Santee Cooper senior vice president of customer service.
“Electric cooperatives in South Carolina are proud to help lead the initiative to develop utility-scale solar generation in the state with our partner, Santee Cooper,” said Mark Svrcek, chief operating officer and senior vice president of corporate strategy at Central Electric Power Cooperative. “Much has been learned in the initial year of operation regarding the performance of the fixed-tilt and tracking panels installed at the site. We expect to find out more in 2015.”
“From a performance perspective, it was a very good year for the solar farm,” said Grant Reeves, senior vice president of TIG Sun Energy. “But more than anything, I believe the construction of Colleton Solar Farm did more to advance solar energy as a potential resource in South Carolina than any other project in the state.”
The Colleton Solar Farm remains the largest solar installation in the history of South Carolina.
The solar array consists of 10,010 photovoltaic panels. Forty percent use single-axis tracking technology to follow the sun across the sky. This action maximizes the production of solar energy. Though more expensive to install initially, the “levelized cost of energy” shows tracking panels at the Colleton Solar Farm were nine percent less per kilowatt-hour (kWh) than fixed panels.
“Impacts on the distribution and generation systems are still being studied,” said Svrcek. “We will continue to monitor the output of the farm as we move into a period where this carbon-free resource becomes a more significant part of a utility’s portfolio.”
The Colleton Solar Farm builds on a 14-year renewable energy history for Santee Cooper and the electric cooperatives. The utilities began generating and distributing renewable landfill gas energy in 2001, and since then have steadily increased renewable generation, using homegrown, South Carolina resources.
