SolarCity has entered into a cooperative research agreement with the Energy Department's National Renewable Energy Laboratory (NREL) to address operational issues associated with high degrees of distributed solar penetration on electrical grids. The work includes collaboration with the Hawaiian Electric Companies to analyze high penetration solar scenarios using advanced modeling and inverter testing at the Energy Systems Integration Facility (ESIF).
Testing with SolarCity and Hawaiian Electric at ESIF is covering the dynamic of inverter-based assets on a grid system, voltage regulation, and bi-directional power flows. Engineers from SolarCity and Hawaiian Electric were at NREL's campus in September to kick off the research project, and in October for a follow up meeting.
"This is an excellent opportunity to utilize ESIF's unique capability to evaluate system-level issues such as anti-islanding, and help reduce risk and minimize the R &D challenges a power distributor or producer may face," NREL's Director of Partnerships for Energy Systems Integration Martha Symko-Davies said.
Hawaiian Electric is providing technical input on testing and setup throughout the process as well as feedback on results.
"We know how important the option of solar is for our customers. Solving these issues requires that everyone - utilities, the solar industry and other leading technical experts like NREL - work together. That's what this work is all about," said Colton Ching, Hawaiian Electric vice president for energy delivery. "With the highest amount of solar in the nation, our utilities are facing potential reliability and safety issues before anywhere else."
Hawaiian Electric has already seen such promising initial test results that they recently announced a plan for approving net-metered customers waiting to interconnect their rooftop solar systems in neighborhoods with high amounts of solar already installed. Applying the preliminary results of NREL and SolarCity's research with Hawaiian Electric, the utility expects that they will approve over the next five months almost all customers who have been awaiting interconnection.
"SolarCity is committed to ensuring that solar is an asset to grid operators, and this partnership will take us further towards that goal," said Peter Rive, SolarCity's co-founder and chief technology officer.
NREL will also evaluate SolarCity's PV generation curtailment hardware and software based on the potential need for PV power curtailment, or the use of less solar power than is potentially available at a specific time, through a remote signal.
"We're pleased that Hawaiian Electric agreed to partner on these important tests and commend them for taking early test results and instituting policy changes that will help Hawai'i's solar industry. Our collaboration has been fruitful and we look forward to continuing our work together," said Jon Yoshimura, SolarCity's Director of Policy and Electricity Markets.
The research was supported by the Office of Energy Efficiency and Renewable Energy. Funding was equally shared between SolarCity and the Energy Department's SunShot Initiative.