“See the video to watch an advanced power diverter cut off 22,000 volts of power in less than 1/20th of a second, preventing ignition of dry brush,” writes Slashdot reader carbonnation.
IEEE Spectrum reports: California utility Pacific Gas & Electric (PG&E) delivered a bitter pill last month when it said that deliberate blackouts to keep its lines from sparking wildfires could be the new normal for millions of customers for the next decade — a dangerous disruption to power-dependent communities that California governor Gavin Newsom says “no state in the 21st Century should experience.”
Grid experts say Newsom is right, because technology available today can slash the risk of grid-induced fires, reducing or eliminating the need for PG&E’s “public safety power shutoffs….”
Some of the most innovative fire-beating grid technologies are the products of an R&D program funded by the state of Victoria in Australia, prompted by deadly grid-sparked bushfires there 10 years ago. Early this year, utilities in Victoria began a massive rollout of one solution: power diverters that are expected to protect all of the substations serving the state’s high fire risk areas by 2024. “It’s not cheap to put one in but once you do it, you’ve got 1,000 kilometers of network that’s suddenly a lot safer,” says Monash University professor Tony Marxsen, former chair of the Australian Energy Market Operator, Australia’s power grid regulator, and chairman of Melbourne-based grid equipment developer IND Technology.
The power diverters — known as Rapid Earth Fault Current Limiters (REFCLs) — react to the surge of current unleashed when a power line strikes the ground or is struck by a tree. When this happens on one of Victoria’s 22-kilovolt distribution circuits, the REFCL instantly begins collapsing the faulted line’s voltage toward 100 volts, and can get there in as few as 40 milliseconds (ms). “If it can do it within 85 ms, you won’t get fires,” he says… Marxsen says 20 to 30 percent of the distribution circuits in PG&E’s territory have the appropriate three-phase design for REFCLs, as do a similar proportion of circuits in the territory of Southern California Edison (which is also grappling with grid-sparked wildfires). “It would certainly offer the option of not shutting down the networks when there’s high fire risk,” he says.