Several articles have mentioned 8 transmission lines were lost to the hurricane (a single big event event). A casual reader might think 8 lines would offer an 8-way level of redundancy.
My WAG is the reality of load vs capacity is more like a N-1 or N-2 redundancy, but that's really just a WAG. It is unclear to me if all 8 lines were damaged by the storm, or if some failed/tripped when loads shifted onto the remaining lines after the first failure occurred (cascading failure). Does anyone know, or has anyone seen, details? On Wed, Sep 1, 2021, 16:12 Sean Donelan <s...@donelan.com> wrote: > One person has died and at least 27 people are being treated for carbon > monoxide poisoning from portable generators. > > Officials are reminding people to operate portable generators only > outside, 20 feet away from homes, doors and windows. Not in carports, > garages, basements. > > To restore power, Entergy has "islanded" (disconnected) the City of New > Orleans from the regional grid and started a local power plant. The > transmission lines were toppled during the storm, but the cables were > still connected to the terminals. Islanding the city makes sense, but I > don't remember a power company islanding large parts of the grid before. > Public officials are now saying it may be 30+ days to fully restore power. > > Entergy has implemented restoration priority, which means hospitals, > public safety and critical infrastructure will be restored first. Along > with some incidental customers on the same circuits. > > > Customers out of service > > Louisiana - 987,588 > Mississippi - 31,516 > Florida - 21,867 > California - 21,339 > Pennsylvania - 10,415 > > Reminder, Puerto Rico still has not fully recovered from hurricanes in > 2017. Puerto Rico still has rolling blackouts. And yes, Puerto Rico is > an island, so its electric grid is naturally an island. > > The major wireless providers have activated their open roaming agreements, > allowing customers to roam on any working infrastructure from other > service providers. They are also waiving overages and many other feeds in > the affected region. Check your service provider's website for details. > > AT&T says 82 percent of its network in service in Louisiana. > > First responders say the AT&T FIRSTNET failed (again) during the > hurricane. > > T-Mobile says 70 percent of its network in service in Louisiana. > > Verizon says it has "gaps in coverage" but its network remains resilient. > I don't know what that means. > > I haven't found reports from cable companies in the region. >