January 2, 2024

QUOTED IN: As reliability concerns with renewables rise, upgrading inverters is urgent, analyst say

A critical technology is needed to sustain the U.S. energy transition’s momentum, according to engineers focused on power system reliability and clean energy.

Inverters with “grid-forming” capabilities, or GFM, are needed to support the growing penetration of inverter-based resources, or IBRs, like wind and solar, according to engineers with the North American Electric Reliability Corporation, or NERC, and engineers with the Energy Systems Integration Group, or ESIG, which advocates for integrating and managing higher levels of renewables.

Inverters convert renewables-generated energy into the alternating current flowing through the U.S. transmission system.

GFM can also provide other system protections, called “stability services,” that detect “abnormal grid operating conditions,” and mitigate them through “disconnection of faulted parts,” NREL said.

“If the fault leads to a blackout, GFM can do a system ‘black start,’ by using IBR-supplied energy to restart generation and rebuild normal operations piece by piece,” Matevosyan said.

But including black start capabilities introduces design and operational challenges, said GridStor Senior Vice President of Engineering, Procurement, Construction and Technical Operations, Daniel Dedrick. And inverters designed for black start are 2% to 5% more expensive and require energy to drive the restart, he added.