PALO ALTO, Calif. (February 1, 2017) – A new Electric Power Research Institute (EPRI) report shows that smart inverters can help grid operators better manage distributed energy resources (DER) on the power grid. The report, “APS Solar Partner Program: Research Highlights,” outlines key research findings from the deployment of 1,598 smart inverters on rooftops as part of the Arizona Public Service (APS) Solar Partner Program (SPP), an initiative that is assessing the impact of using smart inverters to incorporate solar photovoltaic (PV) and battery energy storage on the utility’s distribution system.
An inverter is an electronic device that acts as a gateway between PV generation (solar panels) and the grid. It is designed to efficiently convert direct current (dc) voltage into grid-compatible alternating current (ac) voltage. Inverters also serve as the grid interconnection for battery energy storage systems. Smart inverters include advanced sensing, communications, and control capabilities allowing them to support the grid when needed.
EPRI and APS tested smart inverters to answer questions such as how to configure the devices for maximum benefit, what effect does PV generation have on peak loads, how to use smart inverters to maintain power quality, and what are the true requirements for communicating with these devices. Upcoming research will investigate the potential for energy storage to work alongside smart inverters and other smart grid devices.
Key findings include:
- Distribution system operators were able to successfully communicate commands to the smart inverters on a daily basis, and monitor the outputs, leading to the conclusion that smart inverters can be an asset for grid operators.
- It takes the aggregation of many PV systems to produce a reliable reduction of peak load on distribution equipment. PV that is west-facing generally aligns better with peak loads and produces roughly double the amount of power of south-facing PV on the trial circuits during peak summer periods.
- The inverters followed the commanded functions in the field with limited impact to their energy production; however, extensive preparation was needed to test and verify the performance of the devices.
“Smart inverter technology has the potential of playing a key role in developing a more adaptive and reliable grid,” said Mark McGranaghan, vice president of distribution and utilization at EPRI. “This research project advances industry knowledge of what is needed to more fully integrate DER into the grid.”
On January 31, 2017, the APS Solar Partner Program was awarded Renewable Integration Project of the Year at DistribuTECH 2017. This project is also part of the Integrated Grid Pilot Projects, through which EPRI researchers seek to determine how to optimally integrate DER into the grid. Learn more about EPRI’s Integrated Grid Initiative at integratedgrid.epri.com.
The Electric Power Research Institute, Inc. (EPRI, www.epri.com) conducts research and development relating to the generation, delivery and use of electricity for the benefit of the public. An independent, nonprofit organization, EPRI brings together its scientists and engineers as well as experts from academia and industry to help address challenges in electricity, including reliability, efficiency, affordability, health, safety and the environment. EPRI's members represent approximately 90 percent of the electricity generated and delivered in the United States, and international participation extends to more than 30 countries. EPRI's principal offices and laboratories are located in Palo Alto, Calif.; Charlotte, NC; Knoxville, Tenn.; and Lenox, Mass.