Does the in-city rule mean New York City can never run on imported power alone?

In effect, not under the current rule. NYISO requires a minimum share of the city's peak to come from inside Zone J, so even with more transmission, a floor of local capacity stays required until the rule itself changes.

Is the 80 percent figure fixed?

No. The exact Zone J minimum is recalculated and published by NYISO each year, so the share moves. Treat any single percentage as the value at last public report.

Does clean power built upstate help the city at all?

Yes, for statewide emissions and goals, but it does not satisfy the Zone J floor by itself. Only capacity that sits or lands inside the five boroughs counts toward the in-city requirement.

Will the rule keep old gas plants open?

It can slow their exit. Until enough in-city clean capacity and imports are in place to replace a retiring plant's promise, the zone still needs that capacity, which is part of why some peakers have stayed online.

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Markets · Analysis

Why New York Must Build Power Inside Its Own Borders

A share of the city's peak power has to come from inside the five boroughs, by rule of the grid. That is why retiring an in-city gas plant is not as simple as switching on a clean line upstate.

Filed: October 28, 2026
Section: Markets
Read time: 6 minutes

I · Why the city has its own capacity floor

The grid does not only pay for electricity as it is used. Through a separate market called installed capacity, or ICAP, NYISO pays power plants, batteries, and demand-response programs to promise they will be available when the system is stretched, usually a humid July afternoon. The capacity auction (the recurring process where the grid buys those promises) runs on a seasonal and monthly basis, and the price it sets flows, eventually, into the supply side of your bill.

Zone J is carved out of that statewide market because the city is hard to import into. Only so much power can cross the lines into Manhattan, Brooklyn, and Queens before they are full, so NYISO requires that a minimum share of the city's forecast peak, on the order of 80 percent at last public report, be met by capacity physically inside Zone J. That percentage is recalculated every year and published in NYISO's locational capacity reports, so treat any single number as a snapshot, not a constant.

II · The retirement math

New York's 'peaker rule', a state Department of Environmental Conservation regulation on nitrogen oxide from older simple-cycle gas turbines (the plants that run only on the worst demand days), has been forcing some of the city's oldest peakers offline in stages. Many of those units sit in Zone J, in neighborhoods like Astoria, Sunset Park, and the South Bronx, often right on the waterfront.

Here is the honest arithmetic. Every megawatt of in-city capacity that retires has to be answered by a megawatt of in-city capacity that counts, whether that is a battery, an upgraded plant, a verified demand-response enrollment, or imported power that lands inside the zone. Clean generation built in, say, the Mohawk Valley does not satisfy the Zone J floor on its own, which is why storage going up on city lots and imported hydropower arriving at a city substation matter more to this rule than a wind farm three hundred miles away.

III · Where CHPE and batteries fit

One line already in the works is the Champlain Hudson Power Express, usually shortened to CHPE, a buried cable built to carry roughly 1,250 megawatts of Canadian hydropower from the Quebec border down to a converter station in Astoria, Queens. Because that power lands inside Zone J, it can count toward the in-city requirement in a way most upstate supply cannot. The developer's project page has listed an in-service target in 2026, though transmission schedules of this size slip, so watch the date rather than bank on it.

Battery storage is the other piece. A battery sitting in the Bronx or Brooklyn can charge when the grid is easy and discharge into the peak, and it counts as in-city capacity while it does. Con Edison, the utility that owns the local wires, does not set the capacity rule, but it studies where new batteries and lines can safely connect, and those interconnection studies often decide what actually gets built, and when.

IV · Worth watching this month

1. NYISO's locational capacity reports, which carry the updated Zone J minimum share, publish on a regular cycle and are worth checking for the next revision to the requirement.

2. The CHPE in-service milestone, last targeted by the developer for 2026, is the single date most likely to change the in-city supply picture, and the one most likely to move.

3. State regulators' next stage of the peaker rule, tracked by the Department of Environmental Conservation, will show which remaining in-city turbines are scheduled to run less or retire.

4. Each seasonal installed-capacity auction NYISO runs sets the price that in-city scarcity pushes up, so a sharp move there is an early signal rather than routine noise.

5. Con Edison's interconnection queue, where proposed batteries wait for study, hints at how much in-city capacity is actually on the way.

Questions

Does the in-city rule mean New York City can never run on imported power alone?

In effect, not under the current rule. NYISO requires a minimum share of the city's peak to come from inside Zone J, so even with more transmission, a floor of local capacity stays required until the rule itself changes.
Is the 80 percent figure fixed?

No. The exact Zone J minimum is recalculated and published by NYISO each year, so the share moves. Treat any single percentage as the value at last public report.
Does clean power built upstate help the city at all?

Yes, for statewide emissions and goals, but it does not satisfy the Zone J floor by itself. Only capacity that sits or lands inside the five boroughs counts toward the in-city requirement.
Will the rule keep old gas plants open?

It can slow their exit. Until enough in-city clean capacity and imports are in place to replace a retiring plant's promise, the zone still needs that capacity, which is part of why some peakers have stayed online.

Sources

NYISO installed capacity (ICAP) manual, The grid operator's own manuals defining the capacity market and the Zone J locational requirement. · www.nyiso.com/manuals-tech-bulletins-user-guides
NYISO document library (locational capacity reports), Where the grid operator posts the annual studies that set each zone's minimum in-city capacity share. · www.nyiso.com/library
NY Department of Environmental Conservation, The state air regulator behind the peaker rule on nitrogen oxide, the driver of in-city turbine retirements. · dec.ny.gov
NYSERDA, The state energy authority whose Tier 4 program procured renewable imports, including CHPE, aimed at the city. · www.nyserda.ny.gov
Champlain Hudson Power Express, The developer's project page, with the route into Astoria and the in-service target. · www.chpexpress.com
Con Edison, The city's utility; local grid, interconnection, and billing information for Zone J customers. · www.coned.com