An unplanned grid blackout occurs when an incident trips an entire network. A ripple effect follows throughout the supply chain, although some generating units may be able to ‘island’ and keep running offline. Conventional ‘grid-forming’ recovery traditionally involves restarting a large coal or natural gas resource first, and then progressively rebuilding the network. We would need grid-forming inverters, before we could jump-start a tripped network with renewables, though.
A Research Roadmap for Grid-Forming Inverters
Researchers from National Laboratories, Universities, and U.S. Department of Energy (Solar Energy Technologies Office) published a ‘Research Roadmap on Grid-Forming Inverters’ (see link below). This document outlines a plan to use renewables to restart grids in future, as these resources become a major player.
Grid-forming inverters would become a base-load resource, in this plan to link wind and solar power, and their storage batteries to utility-scale grids:
- Inverters would isolate these renewable generating resources, in the event of a large disturbance, or outage on a grid.
- But they could kick back-in instantly, and in future jump-start the grid upon a signal from the grid controller.
The power distribution industry refers to this process as ‘grid following’ the demand on the network. Although large conventional power is still currently responsible for the initial ‘grid forming’ phase. However, this strategy will become increasingly impractical, as these carbon-intensive resources begin to phase out.
The Core of the Research Roadmap Report
The authors envisage a new world of high-tech inverters, able to jump-start grids from renewable energy feeding though powerful batteries. These are already available in small and microgrids, they say, where we could develop this concept further.
However, much work still needs doing on designing, and creating new grid-forming hardware, software, and controls. Not to mention re-jigging regulatory and technical standards, and developing advanced modelling techniques. These solutions will become critical, as renewable technologies transform our electrical systems, and so we need to start now.
More Information
Inverters and How They Do Their Job
Grid Services Inverters and Storage Batteries
