National Grid Hosting Capacity Map
Feeder-level hosting capacity for National Grid's upstate New York territory — on the same map as parcels, ownership, substations, and New York's SIR interconnection queue.
Explore the Map
Where National Grid's hosting capacity data comes from
National Grid publishes hosting capacity for its New York distribution system through its System Data Portal, one of the commitments the Joint Utilities of New York made under the state's REV proceedings. The map reports how much distributed generation each feeder can take before significant upgrades are needed, expressed as a minimum and maximum for each circuit.
It's genuinely useful data — and a frustrating place to work. The portal is a standalone GIS viewer with no parcel boundaries, no ownership information, and no connection to the interconnection queue. You can see that a feeder has headroom, but not who owns the land under it, whether the ground is buildable, or how many projects are already queued at the substation it feeds.
The same data, with the context that makes it actionable
Sungarden keeps National Grid's hosting capacity map in sync and layers it with everything the portal leaves out: parcel boundaries and ownership for landowner outreach, wetlands and slope for buildability, and New York's SIR queue mapped to each substation so you can see queued megawatts before you commit to a site. Filter for circuits with published capacity above your project size, check what is already installed and queued there, then work outward to the parcels around them.
National Grid also publishes feeder load curves, and Sungarden tracks them — so beyond a static capacity number, you can see how a circuit actually behaves across the day. And because we keep every snapshot of the SIR queue, you can see a project's status history — including withdrawals that reopen room at a substation — rather than only its current state.
The published number is not what's left
A hosting capacity figure is a screening value, not the room remaining on the circuit. In New York the published figure already accounts for the generation installed when the analysis was run — but that analysis runs annually, while the installed and queued totals are refreshed monthly. So the figure is net of generation as of its own refresh date, not as of today, and it is not net of the queue at all.
That makes the arithmetic easy to get wrong in both directions. Subtracting every installed megawatt double-counts what the analysis already removed and makes a workable circuit look dead. Subtracting nothing overstates the room by however much has interconnected since. The only installed figure you can subtract is the generation connected since that refresh date, which is why the utilities publish it as its own number.
Sungarden carries all of it for National Gridas the utility reports it — published minimum and maximum, installed DG, queued DG, and the DG connected since the last analysis refresh — and derives what's left on that basis, recorded per utility rather than assumed. You can filter for circuits with real room rather than paper room.
Feeder primary voltage sits alongside it, which drives interconnection cost more than most screening tools acknowledge — a 27 kV tie is a different budget from a 13.8 kV one before any study begins.
What Sungarden loads for National Grid
- Feeder-level hosting capacity, as published by the utility, with line geometry
- A full feeder dataset — voltage, ratings, and substation links beyond the hosting capacity lines
- Substations
- Feeder load curves
- Parcel boundaries, with owner attributes wherever the source county publishes them (New York)
- Interconnection queue entries, mapped to a substation or feeder where the utility's data identifies one
A published hosting capacity value is the utility's own figure — we republish it rather than recalculating it. Because the New York utilities are not uniform about whether that number is already net of installed and queued generation, we normalize per utility before deriving remaining headroom, so the remainder is comparable across territories.
Frequently asked questions
What is a hosting capacity map?
A hosting capacity map shows how much distributed generation — like solar — each distribution feeder can accommodate without triggering significant system upgrades. Utilities publish it at the feeder level, usually as a range, so developers can screen locations before filing an interconnection application.
Where does National Grid publish its hosting capacity map?
National Grid publishes hosting capacity for its upstate New York service territory through its System Data Portal, as part of the Joint Utilities of New York's distributed system implementation commitments. The portal is a standalone GIS viewer — it shows feeders and capacity values, but no parcels, ownership, or queue context.
What do minimum and maximum hosting capacity mean?
Hosting capacity varies along the length of a feeder, so utilities report it as a range across the points they analyzed. On long rural radial circuits capacity often does thin with distance from the substation, but the profile is not a smooth taper: regulators and capacitors create step changes, and several of the strictest criteria — ground fault overvoltage, substation transformer and bus limits, reverse power flow through the LTC — bind hardest at the substation itself. Treat the range as a screening band for the circuit, not a value you can interpolate for a parcel.
Does hosting capacity tell me what interconnection will cost?
No. Hosting capacity is a screening tool, and the utility's impact study — a CESIR in New York — estimates the actual cost. The largest CESIR line items are usually station-level and protection scope: station breakers, transformer bank work, sub-transmission work, direct transfer trip, relay and telemetry upgrades. None of that is visible on a feeder hosting capacity map, so feeder headroom plus a clean queue is a necessary condition for a cheap interconnection, not a sufficient one. What screening buys you is not paying a study deposit on sites that were never going to work.
How current is the data in Sungarden?
New York's utilities publish their DG interconnection queues to the NY DPS as spreadsheets that post roughly monthly. Sungarden monitors them continuously, so a change appears as soon as it posts, and we keep prior versions so you can see a project's status history rather than just its current state. Hosting capacity is a slower-moving dataset: each utility republishes on its own cadence and we reload it when they do.
Other New York hosting capacity maps
Or start from the New York hosting capacity overview to compare every utility in the state on one map.
Find your next site on National Grid's system.
Get Started For FreeSungarden is an independent platform and is not affiliated with or endorsed by National Grid.