The MTA spent $63 million over the last five years to upgrade the backup power systems that failed Sunday night and caused a catastrophic subway meltdown, records show.
The agency in 2017 approved a contract to upgrade electrical systems at its rail control center and power control center, two buildings in Hell’s Kitchen that are essential to the operation of the subway.
Those upgrades included the installation of a new rooftop emergency generator for the rail control center at an adjacent building, adding to two backup generators that were already in place, MTA officials said.
The work also included an “automatic transfer switch” that would automatically switch power in the building between Con Ed lines and generators as needed, according to the contract description.
When much of the city’s power grid was interrupted at 8:25 p.m. Sunday by an outage Con Edison said lasted “a fraction of a second,” a battery-powered backup system at the rail control center switched on, MTA officials said.
Instead of switching to generators or switching back to Con Ed, the system kept operating on battery power — and the batteries drained after 45 minutes.
“We are investigating why that happened, as are two independent engineering firms,” MTA spokesman Tim Minton said Tuesday.
Additionally, the system didn’t alert managers that it was malfunctioning, and that the rail control center was at risk of losing power, the MTA has said.