U.S. Department of Energy awards study of bifacial PV technology, which could prove a 10% increase in energy output

DNV GL announced that it was selected to receive a USD 200,000 award from the U.S. Department of Energy (DoE) Solar Energy Technologies Office (SETO) for a photovoltaic (PV) research project of bifacial PV technology.

Bifacial PV modules have the potential to increase energy output by 5-10 percent annually in many locations. To achieve commercial viability, the products need to demonstrate their bankability. Common testing models, have begun to incorporate bifacial models. However currently only little validation data for bifacial PV modules exists, which also often lacks third-party evaluation.

The project will validate energy models created for bifacial PV modules by commissioning a large-scale comparative energy yield analysis and creation of energy simulations in PVsyst software, based on the collected field data.

“This study represents the most comprehensive comparative energy yield analysis for bifacial PV modules to date,” said Richard S. Barnes, Executive Vice President, DNV GL – Energy, North America. “Because the solar industry is projected to grow rapidly, it is necessary to understand how new technologies, like bifacial PV modules, will perform.”

“The aim of the study is to accelerate commercial deployment of bifacial PV modules at scale,” said Tara Doyle, head of business development for DNV GL’s PV module testing lab. “If proven viable through extensive performance and reliability testing, bifacial PV modules have the potential to become the preferred technology for ground-mounted PV installations around the world.”

The project will entail collection of field data over the course of one year at DNV GL’s outdoor solar test facility in Davis, California. It will include bifacial and monofacial 1500 V PV modules provided by LONGi Solar, Astronergy Solar, Hanwha Q CELLS and Trina Solar, tested on single-axis trackers provided by solar tracking company NEXTracker, and two albedo ground types. Data acquisition will be highly granular, using actively calibrated equipment. The collected measurements will be used to generate PAN files and subsequent energy simulations in PVsyst.

“Bifacial delivers proven performance with increased energy yield in PV systems, especially in purpose-designed single-axis trackers,” said Dan Shugar, NEXTracker CEO. “World class measurement and verification testing is very helpful to validating the technology, and we’re very pleased to be a part of this important project with DNV GL. It is wonderful that this test is happening at the site in Davis, which has the pedigree of one of the largest collaborations of early PV system testing dating back to the mid-eighties.”

The validation study was awarded as part of the U.S. Department of Energy’s allocation of USD 27.7 million for photovoltaics research and development, issued in conjunction with USD 25.1 million to projects that address other aspects of solar development. Along with other awarded projects that address bifacial PV technology, this study aims to accelerate the commercial adoption of reliable, high-performance PV systems by providing comprehensive field data, data analysis, and PVsyst models that will validate the relevant work that has been done to date.

“Energy modelling validation for bifacial PV modules and systems is needed to provide assurance to owners and financiers that PV systems using this technology will yield expected energy gains,” said Frank Faller, vice president, technology at 8Minutenergy, one of the largest utility scale developers in the U.S. “DNV GL Labs’ study is an important step toward addressing the lack of commercially representative, high-quality field data that’s required to validate contemporary energy models and thus accelerate the bankability of this technology.”

DNV GL was selected as a part of the Energy Department’s FY2018 SETO funding program, an effort to invest in new projects that will lower solar electricity costs and support a growing solar workforce. DNV GL is one of several photovoltaics research projects that will focus on improving the performance and reliability of PV cells, modules, and systems and reducing materials and processing costs.