19
markets.
12
The NYISO filed further revisions to capacity market accreditation, setting the capacity value
for ESRs at 90% for a 4-hour duration resource, dropping to 75% when 1 GW of resources with a duration
limitation are operational in the capacity market.
13
These values were planned to be updated as part of a
quadrennial examination process, which coincides with the timeline for the NYISO Demand Curve process.
However, a new annual process for setting capacity value for ESRs has been initiated through the NYISO’s
Capacity Accreditation process.
Compensation is ultimately determined based on the combination of the resource’s Duration Adjustment
Factor (DAF) and its availability during a peak load window, which is meant to represent the hours where
there is the greatest reliability need. These peak load windows change from summer to winter to account
for the different system conditions and needs throughout the year. For 2022, the six-hour summer peak
load window runs from hour beginning 13 (HB13) to HB18, and the winter peak load window runs from
HB16 to HB21. The eight-hour summer peak load window runs from HB12 to HB19, and the winter peak
load window runs from HB14 to HB21. The NYISO conducts an annual review to determine if these hours
are still the most representative of when reliability is most needed. These capacity rules became effective
in March 2021 and are scheduled to sunset in 2024 when the new marginal capacity accreditation
approach becomes effective.
14
In 2021, the NYISO filed its co-located storage (CSR) model with FERC.
15
This participation model allows
an energy storage resource to pair with an intermittent solar PV or wind resource behind a single point of
injection. Each resource will still bid and operate independently under their respective participation
models (i.e., the ESR will use the ESR participation model described above). However, the co-located
resources can share a single interconnection request. The NYISO concluded in its market design process
that co-locating an ESR with a renewable resource would improve the performance and flexibility of those
renewable resources, reduce development costs by sharing interconnection facilities, and provide better
access to financial incentives. Overall, this participation model helps reduce many barriers to entry for
CSRs while also taking advantage of their ability to support renewable generation. The CSR model became
effective in December 2021.
Currently, the NYISO and its stakeholders are developing a participation model that expands beyond the
co-located storage model.
16
This hybrid storage resource (HSR) model would potentially allow a storage
resource to pair with another solar PV, wind, or run-of-river hydro resource and receive a single point
identifier (PTID), bid, schedule, and settlement; the paired resources may share an interconnection
request as if they were a single resource. As part of this effort, the NYISO is also considering expanding
the CSR model to allow pairing of an ESR with landfill gas, run-of-river hydro, and combustion turbines.
The NYISO expects to develop the market design and functional requirements for this project by the end
12
See Docket ER19-467, New York Independent System Operator, Inc.; Compliance Filing and Request for
Extension of Time of Effective Date (Filed December 3, 2018).
13
See Docket ER19-2276, filed June 27, 2019
14
See Docket ER22-772, Order Accepting Tariff Revisions Subject to Condition, 179 FERC ¶ 61,102 (filed May 10,
2022)
15
See Docket No.ER21-1001, New York Independent System Operator, Inc., Proposed Tariff Revisions to
Implement Co-located Storage Resources (filed January 29, 2021).
16
NYISO Hybrid Aggregated Storage (HSR) Model – Tariff Modifications, Interconnection, ERIS, CRIS.
https://www.nyiso.com/documents/20142/33257202/HSR%20Tariff%20Modifications%20-
%20Interconnection,%20CRIS,%20ERIS.pdf/d04f6b82-b701-0ff1-e2c5-3f4c4a6c1e2d