SPP Interconnection Process — Step by Step
1
Pre-Application & Application
Submit via SPP's Generation Interconnection (GI) portal. $10,000 non-refundable deposit secures queue position. Requires site control documentation and electrical one-line diagram.
SPP Tariff, Attachment V §7.1
2
Interconnection Feasibility Study (IFS)
Optional but recommended. $50,000 fee. Rough screen for thermal and voltage issues. 90-day window. Identifies potential Attachment Facilities and Network Upgrades at high level.
SPP Tariff, Attachment V §7.3
3
DISIS — Definitive System Impact Study
Required for all projects ≥1 MW. Full power-flow analysis in a cluster group. 200-day study window. Shared study cost: $200k for large gen. Identifies required facilities and cost responsibility.
SPP Tariff, Attachment V §7.4
4
Generator Interconnection Study (GIS)
Detailed engineering by TOG (Transmission Owner Group). Direct-assigned facilities finalized. Construction schedule developed. 180-day study window. Project must remain in queue.
SPP Tariff, Attachment V §7.5
5
Generator Interconnection Agreement (GIA)
Execute within 30 days of GIS results. Post IFA: $50/kW (wind), $40/kW (solar/storage). FERC filing required within 30 days. SPP Board approval needed for large or complex projects.
SPP Tariff, Attachment V §7.6
6
Construction & Commercial Operation
SPP issues construction authorization. TO builds system upgrades. Developer builds gen lead with TO oversight. SPP synchronization review. Revenue metering tested. COD granted after final inspection.
SPP Tariff, Attachment V §7.7
SPP DISIS — What Makes It Different
Study Structure
Cluster-Style DISIS Processing
SPP studies groups of projects simultaneously via DISIS. Projects entering in the same 3-month window form a study group and are processed together — reducing re-study iterations compared to serial queue models. Results shared among group members.
SPP Tariff, Attachment V §7.4.1
Queue Flexibility
Suspension Mechanism
SPP allows projects to suspend for 30–90 days (with fee) during DISIS without losing queue position. Useful when developers need more time for permits, site control, or financing. One suspension allowed per project per study phase.
SPP Tariff, Attachment V §7.4.4
Risk Factor
High Wind Concentration Risk
Oklahoma and Kansas areas have seen DISIS study groups with 50+ wind projects. Shared upgrade costs can reach $200M+ in congested corridors, causing 60–70% withdrawal rates within a study group. SW Oklahoma is the highest-risk zone.
SPP DISIS Group Results 2022–2023
Portfolio Policy
Balanced Study Groups
SPP's cluster approach encourages mixed-technology queues. Pure wind clusters in congested areas (SW Oklahoma) trigger more upgrades than mixed solar+wind groups. Developers in congested zones benefit from technology diversification in their cluster.
SPP Planning Criteria §5.3
FERC Order 2023 & SPP Compliance
Compliance Filing
Cluster Readiness Milestones (Dec 2023)
SPP filed compliance tariff implementing FERC Order 2023 readiness milestones. New milestone structure (M1–M5) applies to projects entering queue after Feb 2025. Legacy projects under prior rules remain exempt through existing GIA terms.
FERC Docket ER24-XXX, SPP Compliance
State Policy
Oklahoma & Kansas Wind Leadership
Oklahoma and Kansas lack formal state RPS mandates but have strong industry and policy support for wind. Oklahoma leads the US in wind energy per capita. SPP manages the lion's share of Great Plains renewable interconnection nationally.
SPP Annual State of the Market Report
Seam Relief
SPP-MISO JTIQ — $1.08B Approved
SPP and MISO jointly approved 5 transmission projects under the Joint Targeted Upgrade Initiative (JTIQ) to relieve seam congestion. Total cost: $1.08B. Unlocks ~53 GW of incremental transfer capability between SPP and MISO markets.
MISO-SPP JTIQ Final Report, Oct 2022
Proactive Planning
ITP — Integrated Transmission Planning
SPP's 20-year proactive transmission expansion process. ITP10 (2019) approved 30 new lines at $4B+ investment, socialized across load. Separate from generator interconnection but directly reduces NUC exposure for developers in high-resource areas.
SPP ITP10 Final Report, 2019
Regulatory & Policy Timeline
2019
ITP10 Approved — $4B Proactive Transmission
SPP approved 30 new transmission lines for Kansas, Oklahoma, and Texas panhandle. 100% socialized cost. Designed to unlock 30+ GW of renewable development in the Great Plains corridor.
2022
Transition to Cluster DISIS Model
FERC approved SPP's transition from serial to cluster-based DISIS processing. 18-month transition period for legacy queue participants. Cluster model effective for new entrants in 2023.
October 2022
MISO-SPP JTIQ Approved — 5 Seam Projects
Joint Targeted Upgrade Initiative approved by both RTO boards. 5 transmission projects totaling $1.08B to relieve the heavily congested SPP-MISO seam. FERC approved in 2023.
Q1 2024
SPP Filed FERC Order 2023 Compliance Tariff
SPP's compliance filing implements new readiness milestones (M1–M5), site control requirements, and financial security posting schedule consistent with FERC's landmark interconnection reform order.
Q3 2024 — Now
First DISIS Groups Under New Cluster Model
Approximately 250 projects in active DISIS study under the reformed cluster framework. Results expected Q2 2025. Heavy concentration in Oklahoma wind and Kansas/Colorado solar.
2025
JTIQ Construction Begins on First Two Projects
First two JTIQ seam projects enter construction phase. Expected completion 2027. Will significantly reduce curtailment and improve economics for wind projects in SPP South near the MISO border.
2026
ITP20 Study Launch
SPP launches its 20-year integrated transmission plan assessing 2045 clean energy scenarios. Expected to identify $8–15B in additional needed transmission. Will shape generator interconnection economics for the next decade.