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SPP interconnection

Southwest Power Pool administers generator connection studies and coordinates the required interconnection work with transmission owners.

Guide updated October 9, 2026.

Select ICS or the applicable legacy process​

SPP's current Generator Connection Procedures (GCP) guidance is based on Tariff Attachment AY and addresses the Interconnection Cluster Study (ICS) process. Applications use the SPP Interconnection Management System (SIMS). Identify the applicable study window and governing procedure before selecting forms. GCP guidelines

SPP continues to publish DISIS and Attachment V material alongside the newer ICS resources. Existing projects may need those legacy documents. Use the Generator Interconnection Studies resource index to select the matching checklist, study materials, and process guidance; do not combine requirements from different paths into one assumed checklist.

Assemble the application package​

The current GCP guidance identifies Study Agreement Appendix 3 and Attachments A, B, and C, together with financial and site-control materials. It directs applicants to provide a complete request through SIMS. Current application guidance

For preparation, organize the inputs into clearly owned groups:

  • Applicant identity, contacts, project location, POI, and requested project dates.
  • Technology, nameplate capacity, maximum injection capability, and requested service.
  • Generating-unit, transformer, collector-system, storage, and control information.
  • One-line diagram and geographic layout tied to the proposed connection.
  • Plant and gen-tie site evidence, applicable attestations, and supporting maps.
  • Study deposits, security documentation, and submission acknowledgements.

Preserve the distinction between equipment nameplate, requested injection, and deliverability. The same number should appear in multiple places only when it represents the same engineering or service quantity.

Prepare the engineering evidence​

Use a common equipment schedule to develop the one-line and technical attachments. For internal review, trace every transformer and generating-unit rating back to its source, and identify the impedance bases and operating conditions used in calculations. Keep storage charging assumptions separate from export capability.

SPP publishes EMT model requirements for inverter-based resources, including documentation, equipment-specific controls, plant representation, and test material. Determine the applicable delivery milestone using the current process guidance and project requests. A PSCAD file name alone does not describe model completeness or acceptance. EMT model requirements

A useful model manifest includes the supplier, model version, settings, software dependencies, represented equipment, and test results. Document deviations and unknowns so they can be resolved with the supplier and study team. Preserve the relationship between the positive-sequence representation, EMT representation, and physical design.

Track land and financial obligations​

SPP's current resource index includes a specific ICS site-control attestation, site-control criteria, and ICS financial requirements, risks, and refunds material. Use these matching documents for the selected process and window. Site and finance resources

For internal tracking, separate plant-site parcels from gen-tie right-of-way. Map each document to the relevant area or route segment, and record term, ownership or option status, and unresolved gaps. Maintain a financial register that distinguishes study funding from security, includes the project identifier and recipient, and records both submission and acknowledgement. Confirm amounts and permitted instruments against the controlling documents.

Review for consistency and completeness​

Recommended checks before submitting include:

  1. Compare Appendix 3 and its attachments with the equipment schedule and one-line.
  2. Reconcile the POI description, coordinates, voltage, and geographic map.
  3. Check requested injection and service values against the modeled configuration.
  4. Verify that site evidence covers the layout being submitted.
  5. Retain a dated package manifest and track each deficiency response separately.

Use SPP's designated support channel for process questions, and record the response with the specific request it resolves. The GI resource index links to the relevant support and submission guides.

Official sources and scope​

Start with the SPP GI resource index, GCP guidelines, and EMT model requirements.

This guide supports preparation and navigation. The effective tariff, current cycle instructions, and project-specific transmission-owner requirements control. A completed checklist does not establish application acceptance or compliance.