Neptune
NYISO ↔ PJM · HVDC line (line-commutated)
An undersea HVDC cable from Sayreville, New Jersey to the Duffy Avenue converter in Hicksville, Long Island, importing PJM power into Long Island.
Operator readings
Compare each operator’s reading at its stated time. Scheduled transfers and metered physical flow measure different things.
- As NYISO reports it
- 610 MW · PJM → NYISO
Current reading · limit this way 660 MW · 38 MW left to schedule · as of Nov 10, 6:45 PM EST
- As PJM reports it
- 599 MW · PJM → NYISO
Current reading · as of Nov 10, 6:40 PM EST
Last 30 days
Hourly readings, signed so that up is power leaving the market. Each series identifies whether it measures flow or a transfer schedule.
Above zero: NYISO → PJM. Below: the reverse.
- Usual direction
- PJM → NYISO in 84% of hours
0% out, 84% in, 16% idle across 721 hours
- Average
- 538 MW · PJM → NYISO
- When busy
- 660 MW
95th percentile of hourly flow either way
- Peak NYISO → PJM
- 0 MW
- Peak PJM → NYISO
- 660 MW
- Direction changes
- 0
- Hours near its rating
- 556 of 721
At 95% or more of 660 MW
Hardware
Its terminals, placed from named HIFLD substations or other cited geospatial sources where available.
- Converter
- Sayreville, NJ
40.4742, -74.3533 · 500 kV · representative location
- Converter
- Duffy Avenue converter, NY
40.7608, -73.5514 · 500 kV
Sources and method
Readings come from NYISO and PJM interface readings. Each value is shown with its operator and source time; direction is normalized from that operator’s sign convention toward or away from NYISO. A rating describes the equipment; an operator’s posted directional limit, when available, is a separate operating value. The map point identifies a sourced terminal or crossing where available, or a representative connection point; it does not trace the full route.