Advanced Grid-Friendly Controls Demonstration for Utility-Scale Photovoltaic Power Plants

As renewable technologies become more common on the grid, they will need to provide a range of essential reliability services. NREL researchers are working with vendors, integrators, and utilities to develop and evaluate photovoltaic (PV) power plants with advanced grid-friendly capabilities.

Graph of power over time that shows a PV plant varying output to follow an automatic generation control set point.

In this example of a 300-MW PV plant providing ancillary service, the plant is curtailed (orange trace) to operate 30 MW below its peak power (green trace) so it can follow the automatic generation control set point (red trace) sent by the system operator.

As California marches toward fulfilling—and likely exceeding—its renewable portfolio standard, grid operators are beginning to face operational challenges that could have implications for renewable generators in ancillary service markets. In this project, NREL’s strategic partnership with California Independent System Operator (CAISO) and First Solar resulted in the implementation and testing of grid-friendly controls on a 300-MW PV power plant in CAISO’s footprint. NREL, CAISO, and First Solar conducted demonstration tests that used the advanced capabilities of modern PV power plants to provide essential reliability services to the CAISO power system.

Similar projects were conducted in 2015 at a 20-MW PV plant in Puerto Rico and a 22-MW PV plant in West Texas. These projects demonstrated that utility-scale PV can provide grid services that impact system reliability. The Puerto Rico project, especially, demonstrated the ability of PV generation to provide frequency regulation for the whole island system. Together, these demonstration projects help bridge gaps in perspective among stakeholder groups.


Demonstration of Essential Reliability Services by a 300-MW Solar Photovoltaic Power Plant, NREL Technical Report (2017)

Advanced Grid-Friendly Controls Demonstration Project for Utility-Scale PV Power Plants, NREL Technical Report (2016)


Vahan Gevorgian

Chief Engineer