The groundbreaking public-private partnership between CPS Energy and OCI Solar, which will result in more than 400 MW of solar power for San Antonio, is expected to catapult Texas into the top five solar-producing states in the country.
CPS Energy CEO Doyle Beneby, who not only made the decision to invest in “big solar,” but also insisted on a substantial economic development component to the deal, will accept the Solar Electric Power Association’s 2012 Utility CEO of the Year award today in Orlando, Fla.
“Mr. Beneby is moving San Antonio to the forefront of affordable solar energy in the U.S. and leading a charge that has the potential of transforming the region into a center for clean energy development,” said Julia Hamm, SEPA president and CEO.
Beneby’s decision to invest heavily in utility scale solar — that is, large installations (usually between 10 MW and 200 MW) that feed power into the grid — is based on economics.
In addition to basic economies-of-scale cost savings, large installations can be sited for maximum exposure to the sun. While many rooftops get full sun, they’re not always angled to allow panels to work at maximum efficiency. Also, rooftop panels are fixed, where utility-scale panels can track the sun, meaning that not only can they can generate more power, they can do it for a longer period of time each day.
While CPS Energy’s first foray into utility scale solar, the 14 MW Blue Wing site, is made up of fixed panels, the recently-completed SunEdison Centennial installations track the sun on a single axis — and the 400 MW OCI installations will be dual-axis, said Cris Eugster, CPS Energy’s chief sustainability officer.
“Tracking is the future,” said Eugster, who recently joined the SEPA board.
Given that increased efficiency, utility scale solar can produce as much as 50 percent more power than a fixed-panel rooftop installation, he said. Perhaps even more crucially, tracking solar generates power during more of the peak hours of 3 p.m. to 7 p.m., when demand is greatest, and therefore most costly to the utility.
This graphic shows how much more of peak load a tracking system can meet compared to even an optimally-sited fixed panel installation.
Those longer hours point to another benefit of large-scale solar over individual rooftop installation: When the power generated from a rooftop installation begins to fade, that house once again relies on the electrical grid, but the homeowner isn’t paying the full costs of that infrastructure any longer. That shifts those costs — for alternative power generation, poles and wires and maintenance — to CPS Energy’s remaining customers, many of whom are low-income and already struggle to pay their utility bills.
With utility-scale, all customers benefit from the solar power and all pay for the infrastructure costs necessary to keep the system going.
Utility scale solar is gaining fans at the state level, too, as Texas’ electrical grid struggles to meet peak demand on the hottest summer days.
“One thing that’s clear to me is that solar will help,” Texas Public Utility Commissioner Rolando Pablos said last month at the Texas Energy Symposium, hosted by Solar San Antonio, by far the earliest and most fervent supporters of solar power in the region.
Large scale solar is the most economic, and the best way to spread costs among ratepayers, Pablos said, praising CPS Energy’s partnership with OCI Solar.
CPS Energy is still committed to rooftop solar — the utility has one of the most generous rebates in the state, which has allowed for more than 600 installations (and another 181 in the pipeline) in the last few years.
“We’re taking a calculated approach to solar,” said Beneby. “With a focus on utility scale first, as a supplement to low-cost natural gas, nuclear power and cleaner burning coal, we can get the most bang for the buck. As we complete that objective, we’ll turn more attention to maximizing opportunities with commercial customers and then a greater focus on residential installations.”