Contract development

Interconnection generation process

After a resource has completed the study phase and transmission plan deliverability of the interconnection process the customer must sign contracts and install metering and telemetry equipment. The ISO must model the resource in market systems before participation in the wholesale power market is allowed.

Generators within the ISO balancing area must establish:

Generator interconnection agreement

An interconnection 2-party agreement is established between the participating transmission owner (PTO) and interconnection customer, when the generating facility is connected to distribution facility. 

A 3-party agreement is established when a generating facility is connected to the California ISO controlled grid. A generator interconnection agreement is established prior to executing the market agreements required for interconnection with the California ISO.

Market agreements

Generators must enter into a participating generator agreement (PGA) and meter service agreement (MSA) with the ISO. After a resource has completed the study phases of the interconnection process, the interconnection customer must sign contracts that are part of the New Resource Implementation bucket 2 process.

ISO controlled grid connected generating facility

If you are a generating facility already connected to the California ISO controlled grid, please initiate the conversion process by sending the Interconnection Request Form for Modifications/Repowers/Conversions to and, which must include the most recent one-line diagram of the generating unit(s) showing the interconnection to the ISO controlled grid. The ISO will review and confirm the interconnection to the ISO controlled grid. Following this determination, please submit the below listed information to Please review the Business Practice Manual (BPM) for Generator Management for the detailed process for conversion to ISO markets for existing generators. 

Non-ISO controlled grid connected generating facility

If you are not connected to the ISO controlled grid, please commence the New Resource Implementation (NRI) process.

Conversion from two-party to three-party interconnection agreements

A specific interconnecting request form is used for projects converting from a two-party interconnection agreement with a Participating Transmission Owner (PTO) to three-party interconnection agreements to include the ISO.

Request transition to ISO interconnection

  • Either interconnection customer or participating transmission owner (PTO) sends email request to Regulatory Contracts including single-line diagram
  • ISO confirms 2- or 3-party agreement

Interconnection customer submits information and data

Step 1

  • Draft affidavit
  • Conversion interconnection request
  • Create RIMS project

Step 2

  • Positive sequence load flow files
  • Attachment A to Appendix 1
  • Copy of Power Purchase Agreement (PPA), Special Facilities Agreement, and study report (if applicable)
  • Initiate new resource interconnection (NRI) process

Validate and execute Generator Interconnection Agreement (GIA)

  • ISO validates information and data provided
  • ISO determines net MW to grid 
  • Interconnection customer submits notarized affidavit to ISO and PTO
  • PTO tenders GIA to interconnection customer and ISO
  • Execute GIA

Related ISO Tariff and Business Practice Manuals

To participate in the market, generators must enter into a Generator Interconnection Agreement (GIA), Participating Generator Agreement (PGA), and a Meter Service Agreement (MSA) with the ISO. For additional information on contract development, please email

Back to top