The National Renewable Energy Laboratory (NREL) in Golden, CO, is a hotbed for emerging renewable energy technologies, a place where advances are made and technologies are tested. But now it’s installing commercial solar panels as part of Sandia National Laboratory’s PV-Lifetime project in a test field to show the public how the panels perform over time.
In 2017 the lab is installing 50 solar panels sourced from three manufacturers and it plans to add 50 more panels from other companies in each of the next two years. "We're going to buy up modules that represent the average cross-section of installed modules each year in the United States and see how they do over time," said Chris Deline, an engineer at NREL.
The lab will measure how efficient the solar panels are at converting sunlight into electricity and how that changes over time. The panels have a degradation rate—usually expected to be 0.5 percent to 1 percent a year—and how each company’s solar panels actually perform will be posted on NREL's website.
"It is important to determine how the degradation rates vary because a module that maintains its output for many years and then fails on the last day of its life will generate a lot more electricity than a module that degrades 10 percent in the first year and then is stable," said Sarah Kurtz, an NREL research fellow and co-director of the National Center for Photovoltaics. A weakened solder bond, for example, could break and that would throw off the performance of a module.
It’s a unique test facility for the lab. At another building on NREL’s campus, the Outdoor Test Facility (OTF), the lab has smaller solar array field where it can perform some real world tests of solar panels. The OTF has been testing some of the same solar panels on the site for years. This new facility changes that.
”The main difference is this large grassy area gives us the capability of having larger systems," Deline said. "Over at the OTF, because of our space constraints, we can only have 8 or 10 modules for a given system. With this one we're able to do side-by-side comparisons of larger systems."
In all, the solar array field will house four rows of solar panels. Already the first row of panels is operational. It’s for NREL partner manufacturer modules. NREL said it is already testing modules from SolarCity against those made by a Chinese manufacturer. Such contracted testing, however, will remain confidential, according to NREL.
"This greatly expands our ability to work with commercial partners," Deline said. "The other neat thing is it allows us to get access to some of these cutting-edge products because a lot of this stuff is not commercially available. We're like customer No. 1 for some of these new technologies. It gives us the ability to get in at the forefront."
The second row and subsequent rows will consist of commercially available solar panels. The degradation rates of those modules will be made public.Tweet