SolarCity's Hawaiian study reveals grid regulation potential of inverters

A groundbreaking study by solar leasing company SolarCity, the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) and Hawaiian Electric has explored the potential of solar inverters to act as junior grid regulators, and found that the technology holds the key to overcoming transient load rejection overvoltage (LRO) concerns. Concerns over LRO limitations have stymied solar growth in regions where grid capacity restraints have been paramount, and the issue has long been a limiting factor governing Hawaiian Electric's current integration policies on high penetration of distributed generation (DG). However, in tackling these limitations, inverter testing carried out at NREL's Energy Systems Integration Facility (ESIF) revealed that most inverter technology possesses the capability of safely managing distributed energy on to the grid, finding that a typical inverter could act as a proxy "junior grid", thus overcoming the technical barriers that have limited DG penetration in Hawaii and elsewhere in the U.S. The report, titled Inverter Load Rejection Over-Voltage Testing: SolarCity CRADA Task 1a Final Report, sought to provide an insight into how to overcome such interconnection barriers. According to SolarCity, as a direct result of this testing Hawaiian Electric is now prepared to increase circuit thresholds on its grid from current levels of 120% daytime minimum load (DML) of DG, to 250% ...

Den vollständigen Artikel lesen ...