Inside the NYC Power Stations That Keep Trains Moving — or Bring Them to a Halt

It was one of the worst commutes in years. A power outage stranded more than 3,500 New York City subway riders in stuffy, crowded train cars for more than two hours on Dec. 11, 2024, during the evening rush.

Firefighters evacuated riders from the disabled trains, but not before some passengers were forced to relieve themselves between cars, according to people who were present. The ensuing delays, which affected the A, C, F and G lines in Brooklyn, stretched well into the morning, snarling the commute for thousands more riders.

But the foul-up didn’t start on the tracks — it began about 40 feet beneath the sidewalk, in a concrete bunker called a substation, like this one.

The Metropolitan Transportation Authority, which runs the New York City subway, operates 225 of these substations. They provide the electricity that keeps trains moving.

Some are deep underground, while others are in fortresslike buildings close to train tracks. Dozens of the facilities are nearing 100 years old, and some components have gone decades without substantial upgrades.

The electrical outage in 2024 started after a critical failure in a Downtown Brooklyn substation that dates to the 1930s. Heavy rainfall most likely seeped into equipment and caused an explosion so forceful that it knocked a door off its hinges, according to the M.T.A.

Without adequate electricity, trains that were closest to the damaged substation could not move, and their ventilation systems shut down.

Such major failures are rare, but are responsible for some of the subway’s worst logjams, said Jamie Torres-Springer, the head of the authority’s construction and development division.

“That’s what causes the most difficult, painful disruptions in the system that drive people out of their minds,” he said.

In hopes of preventing the next nightmare commute, the M.T.A. is making the biggest investment in power in its history. Transit officials plan to spend $4 billion on new power systems by 2029, including upgrades to 75 subway substations. That’s three times as many as were renovated during the last major round of repairs, which ended in 2024.

They have their work cut out for them.

Hidden beneath a steel-trap door on the Upper West Side of Manhattan, 36 steps below the surface, is one of the system’s oldest remaining substations.

“This is a blast from the past,” said David Jacobs, the M.T.A.’s acting general superintendent for power stations, who donned a hard hat and safety glasses on a recent weekday before disappearing into the underground space.

The substation, near 73rd Street and Central Park West, was built in the 1930s, and is expected to be renovated during the current blitz.

A dirty tarp hung in one corner of the cavernous room, to catch water that seeped through worn concrete. Rows of machines hummed with the constant surge of power feeding the electrified third rail on nearby tracks.

It takes about 2 billion kilowatt-hours of electricity to run the subway system annually. That’s enough power to light 128,000 homes for a year.

The substations’ main function is to convert raw, high-voltage electricity from the electrical grid into lower-voltage power that can be delivered to the third rail.

But the aging equipment has become progressively less efficient and reliable, and harder to maintain.

The substations are spaced out across the city, to help keep electricity flowing to trains even if one of them malfunctions. But the equipment has sometimes failed when asked to carry an extra load, leading to cascading problems.

Last year, there were 758 “major incidents” on the subway, ones in which 50 or more trains were delayed. Substations cause a small but disruptive share of the problems, according to M.T.A. data.

“Power is everything,” said John Ross, a recently retired transit worker who was dispatched to help after several service disruptions in the subway, including the outage in 2024. “When it breaks, it breaks good.”

M.T.A. officials assessed the condition of every substation in recent years, and found that 36 percent of the equipment was in poor condition or in need of replacement.

While the main purpose of the upgrades is to reduce train delays, the changes have other benefits. The M.T.A. is installing a new signal system that relies on wireless technology to automatically control train movement.

The system, known as Communications-Based Train Control, or C.B.T.C., will allow trains to operate more reliably. It will also enable transit workers to monitor train traffic more closely from a dedicated room in Midtown Manhattan, known as the operations control center.

But switching to that signal system requires upgrading the rest of the subway’s archaic equipment. “In order to run more trains, we need more power,” Mr. Torres-Springer said.

For Mr. Jacobs, 36, who joined the M.T.A. nearly two decades ago as an electrical apprentice, working with machines younger than him would be a welcome change.

Today he runs a department of almost 400 people, and much of the work remains hands-on: diagnosing problems in the machinery by reading small flags with numbered codes, searching for replacement parts that are no longer manufactured, and generally eking out more life from obsolete machines.

“I do love this equipment,” he said with a smile.

But he’s ready for an upgrade to something built in this century.

“It’s like a B.M.W. versus a 1940 Cadillac.”