Energy Rights
ERIS — Energy Resource Interconnection Service
Right to inject energy into the grid. All projects receive ERIS automatically upon interconnection. No deliverability test required. Allows energy market participation but not capacity market bidding.
OATT Attachment X, Section 30.4
Capacity Rights
CRIS — Capacity Resource Interconnection Service
Required for NYISO capacity markets (ICAP). Must pass the Deliverability Interconnection Standard (DIS) or fund System Deliverability Upgrades (SDUs). Primary revenue driver for storage projects. Can be partial — only deliverable MW awarded.
OATT Attachment X, Section 30.4
Upgrade Types
SUF vs SDU — What's the Difference
SUF (System Upgrade Facility) — project-specific local interconnection upgrade. Allocated solely to the triggering project. SDU (System Deliverability Upgrade) — shared transmission upgrade for deliverability. Allocated proportionally across all benefitting projects.
OATT Attachment S — The Rules
Headroom
Electrical & Functional Headroom Payments
When a new project uses excess capacity created by a prior Class Year's SUF or SDU, it pays headroom to the prior Class Year developer. Electrical headroom measured in Amperes. Functional headroom split equally by project count. Expires after 10 years.
OATT Attachment S, Section 25.8.7
Cost Allocation
Attachment S Rules
SUF costs: 100% to triggering project. SDU costs: prorated by each project's contribution to the binding constraint (Amperes or MW). Projects that reject cost allocations are removed from CRIS eligibility but may stay in queue on ERIS.
OATT Attachment S — The Rules
New Rules — 2024
Attachment HH — Transition Cluster Process
Replaces Attachments S, X, Z for new projects from May 2024. Introduces structured cluster timelines, readiness deposits, and hard deadlines. C24 is the first cluster under HH. New SDU cost allocation methodology proposed — dramatically reduces costs for most projects except LI East and Zone J.
OATT Attachment HH — Active Watch
Study System
ATBA and ATRA — The Two Study Cases
ATBA (Annual Transmission Baseline Assessment) — the pre-project base case. Represents a 5-year-ahead summer peak without Class Year projects. ATRA (Annual Transmission Reliability Assessment) — ATBA plus all Class Year projects at full output. Differences between ATBA and ATRA identify what each project adds to the system.
Attachment S, Section 25.5.4
Deliverability Test
DIS — Deliverability Interconnection Standard
NYISO tests whether a project at its requested CRIS MW level is deliverable throughout the NY Capacity Region. If not, SDUs are required. The LI Byway test is the specific test for Zone K projects — the Pilgrim-West Bus PAR is the binding constraint.
Attachment S, Section 25.7
Decision Process
30-Day Decision Periods & Security Posting
After OC approval of the cost allocation report, developers have 30 days to accept or reject. Accepting = must post security with the TO within 5 business days. If any developer rejects (Non-Acceptance Event), NYISO recalculates costs for remaining projects within 14 days. Process iterates until all accept or withdraw.
Attachment S, Section 25.8.2-25.8.4