Frequently Asked Questions

Applying for Interconnection

Why do I need an Interconnection Agreement?

Regardless of your Wholesale Generation category, you'll need an Interconnection Agreement with PG&E to meet federal and state regulations. The reasons for this are:

  • Safety—All electrical generating systems are potentially dangerous if they are not operated properly. If your system connects to PG&E's electric grid, safeguards for protecting you, our personnel and other customers must be in place.
  • Reliability—PG&E must be able to meet our customers' expectation that power is always available when needed. If a fault or trip occurs on a customer's generation system, we must be able to isolate the problem so other customers can continue to enjoy reliable power.
  • Government regulation—The Federal Government and State of California require the interconnection agreement.

How do I submit a Generation Interconnection Request?

Wholesale Distribution Generation Interconnection Requests: PG&E requires you to submit your Wholesale Distribution Generation Interconnection Requests via an online application form. You can use our Application Checklist (PDF, 141 KB) to guide you through this process. You'll find more information about the process in Section 1.3 of Attachment I: Generation Interconnection Procedures (GIP) (PDF, 1.5 MB) in PG&E's Wholesale Distribution Tariff.

Wholesale Transmission Generation Interconnection Requests: If you are applying for interconnection to PG&E's Transmission system, you must submit your request to the California Independent System Operator (CAISO) using this form. Refer to Appendix Y, Generator Interconnection Procedures (GIP) of the CAISO Tariff for more information.

Who handles the interconnection application process?

PG&E handles the interconnection procedures for generators interconnecting with the Wholesale Distribution system. New applicants for interconnection under this system should follow the procedures and forms in Attachment I of PG&E’s Wholesale Distribution Tariff (PDF, 1.5 MB). The California Independent System Operator (CAISO) handles the interconnection procedures for generators interconnecting with the Wholesale Transmission system. New applicants for interconnection under this system should follow the procedures and forms in Appendix Y, Generator Interconnection Procedures (GIP) of the CAISO Tariff.

What is the process and timelines for applying for interconnection?

For an overview of application timelines for distribution interconnection requests, view the Wholesale Distribution Process Flow Overview (PDF, 201 KB). For an overview of application timelines for transmission interconnection requests, view the Wholesale Transmission Process Flow Overview (PDF, 202 KB).

Can I submit simultaneous Interconnection Requests to both PG&E and CAISO?

No. Because of the growing number of projects and the importance of accurately modeling systems and identifying upgrades necessary to accommodate interconnection requests, PG&E cannot allow applicants to submit a distribution interconnection application and a transmission interconnection application for the same project. Interconnection Customers may choose to submit applications in a serial fashion, but not in parallel. That is, the former Interconnection Request must be withdrawn prior to submittal of the latter. PG&E has established this policy to maintain equitable treatment for all developers.

Can I ask PG&E for an extension during the Wholesale Distribution Interconnection Application Process?

PG&E maintains a public queue (XLS, 289 KB) for the Federal Energy Regulatory Commission (FERC) Generation Interconnection Procedures (GIP) distribution level projects. PG&E will enforce the following guidelines to ensure equitable treatment:

  1. PG&E will grant one extension of twenty (20) Business Days wherever the GIP allows for an extension.
  2. Interconnection Customers cannot request to place projects on hold.

Can I modify my Wholesale Distribution Interconnection Request after I submit it?

Any modification to machine data, equipment configuration or the interconnection site of the Generating Facility that has not been agreed upon in writing by the Distribution Provider and the Interconnection Customer may be considered a withdrawal of the Interconnection Request. If this happens, the Interconnection Customer may need to submit a new Interconnection Request unless each party has properly notified the other and a reasonable time to cure the problems created by the changes are undertaken. For further information regarding permitted modifications please see Section 3.5.8, Modifications in Between the System Impact and Facilities Study and Section 4.11.2 Modifications in Between the Phase I and Phase II Interconnection Studies of the Wholesale Distribution Tariff (WDT) Attachment I: Generation Interconnection Procedures (GIP) (PDF, 1.5 MB), and Section R.3.d.v of Rule 21, Modifications. Please note that modifications are not permitted to the Fast Track process under either the WDT or Rule 21.

What do I need to provide PG&E for my Interconnection Request for a Wholesale Distribution project to be considered complete and for me to be assigned a queue position?

Your application must include the following to be considered complete (Administrative Data Adequacy) and for your project to be assigned a queue position:

  1. Complete the {Wholesale Distribution Interconnection Request Form (Attachment 2), the Rule 21 Exporting Generator Interconnection Request, or the Generating Facility Interconnection Application For Non-Export Or Certain Net Energy Metered Generating Facilities (Between 30 KW and 1,000 KW)}
  2. Complete Appendix A (PDF, 208 KB)
  3. Application Fee – Generation Interconnection Services will send an Invoice Letter with instructions on a wire payment when an Interconnection Request is received
  4. Single-Line Diagram (PDF, 249 KB)
  5. Site Plan (PDF, 533 KB)
  6. Site Control or Exclusivity per Section 1.5 of Attachment I: Generation Interconnection Procedures (GIP) in PG&E's {Wholesale Distribution Tariff and Section E.2.d. of Rule 21}

When the Interconnection Request is complete, you'll be assigned a queue position Please refer to the Wholesale Generation Interconnection Services (GIS) webpage or Rule 21 for more information on items required and timelines for completing an Interconnection Request for the different Wholesale and Rule 21 programs.

What is a Single-Line Diagram?

A Single-Line Diagram is a schematic drawing showing the major electric switchgear, protective function devices (including relays, current transformer and potential transformer configurations/wiring and circuit breakers/fuses), wires, generators, transformers, meters and other devices, providing relevant details to communicate to a qualified engineer the essential design and safety of the system being considered. View an example of a Single-Line Diagram >> (PDF, 249 KB)

How can I prove that I have "Site Control"?

You can demonstrate site control through documentation showing (1) ownership of a leasehold interest in or a right to develop a site for the purpose of constructing the Generating Facility; (2) an option to purchase or acquire a leasehold site for such purpose; or (3) an exclusivity or other business relationship between Interconnection Customer and the entity having the right to sell, lease or grant you the right to possess or occupy a site for such purpose. View examples >> (PDF, 1.5 MB)

Interconnection Processes and Studies

What is the purpose of a scoping meeting?

After we receive your completed application package and applicable fees, you will be invited to meet with PG&E to discuss the scope of your project. This meeting is called a scoping meeting. During your scoping meeting, you and representatives from PG&E's Generation Interconnection Services will:

  • Discuss the PG&E engineering team's initial assessment of the impact of and minimum requirements for establishing an electrical connection between your installation and our distribution system
  • Set expectations for how long it will take PG&E to study and fully assess the impact and requirements described above
  • Give you an overview of the study process and key milestones

How much will interconnection cost?

The cost to interconnect to PG&E’s electric system is site-specific. The electric system nearest to your site may or may not have the capacity to receive the amount of generation you propose. As a result, there may be specific interconnection facilities, distribution upgrades and network upgrades necessary to accommodate the interconnection request. The interconnection study process will inform you of the scope, schedule and cost of any upgrades your project requires.

What are Financial Security Postings?

Section 4.23 of the Generation Interconnection Procedures and Section 4.a of Rule 21 requires Interconnection Customers to post Interconnection Financial Security to remain in the Interconnection Study Process. The Interconnection Financial Security posted may be any combination of the following types of financial instruments:

  1. An irrevocable and unconditional letter of credit issued by a bank or financial institution that has a credit rating of A or better by Standard and Poor’s or A2 or better by Moody’s;
  2. An irrevocable and unconditional surety bond issued by an insurance company that has a credit rating of A or better by Standard and Poor’s or A2 or better by Moody’s;
  3. An unconditional and irrevocable guaranty issued by a company that has a credit rating of A or better by Standard and Poor’s or A2 or better by Moody’s;
  4. A cash deposit standing to the credit of the Distribution Provider and in an interest-bearing escrow account maintained at a bank or financial institution that is reasonably acceptable to the Distribution Provider;
  5. A certificate of deposit in the name of the Distribution Provider issued by a bank or financial institution that has a credit rating of A or better by Standard and Poor’s or A2 or better by Moody’s; or
  6. A payment bond certificate in the name of the Distribution Provider issued by a bank or financial institution that has a credit rating of A or better by Standard and Poor’s or A2 or better by Moody’s.

Do I qualify for the Fast Track Interconnection process?

The Fast Track process is for existing facilities with infrastructure already built and for new proposed interconnections of certified generation without any new construction of upgrades (construction of interconnection facilities is permitted). Please refer to the screens in Section 2.2.1 of Attachment I: GIP of the Wholesale Distribution Tariff (PDF, 1.5 MB) and F.1.b of Rule 21 for more information on the requirements you'll need to meet to qualify for the Fast Track process.

What's the difference between the Independent Study Process (ISP) and Cluster Study Process (CSP)?

  • An ISP evaluates an interconnection request for a generating facility independently of other projects. An ISP involves a System Impact Study and a Facilities Impact Study, each of which must be completed within 60 business days. To become eligible for an ISP, you must pass an Electrical Independence Test (EIT) after you apply. This test involves determinating if another, earlier-queued interconnection request in study is in an area that will have an electrical dependence (both on distribution and transmission) on the interconnection request undergoing the EIT. To find out your potential for passing this test, check the public queue (XLS, 289 KB) for active projects connecting to the substations at your point of interconnection. The ISP study process may take 6 to 12 months. You may apply for an ISP at any time. But if your project fails either part of the EIT, you will be required to wait:
    • Until the earlier-queued interconnection request completes the study process (Rule 21 only)
    • Until the next Cluster window to apply under the Cluster Study Process, or
    • 12 months from the date you were informed of the failure of the EIT to reapply under the ISP for a similar point of interconnection (WDT only)
  • A CSP evaluates a group of interconnection requests collectively. You may apply for a CSP (under the WDT) only during the cluster window each year. Engineering analyses for CSP requests are conducted in two phases. Phase I and Phase II studies identify distribution and reliability network issues or upgrades required to mitigate thermal overloads and voltage violations and address short-circuit, stability and other reliability issues.

What's the difference between Full-Capacity Delivery and Energy-Only Delivery?

  • Full-Capacity Delivery means your generating facility will interconnect with PG&E’s distribution system and will deliver its full output to the aggregate of load on the CAISO grid, consistent with the CAISO reliability criteria, procedures and On-Peak Deliverability Assessment. View more information about CAISO requirements >> Please also make sure to become familiar with the requirements of your Power Purchase Agreement for resource adequacy. If you are applying for Full-Capacity Delivery, you must commit to delivering at maximum power whenever possible. This requires a network-wide engineering analysis to mitigate any potential impact on transmission-level voltage facilities.
  • Energy-Only Delivery means your generating facility will interconnect to the PG&E distribution system but will not deliver its full output to the aggregate of load on the grid. In this case, you are responsible only for the costs of reliability network upgrades and not for the costs of delivery network upgrades. An Energy-Only project may deliver intermittently and be asked to shut down if electrical constraints occur.

How can I pursue Full-Capacity Deliverability status?

Once your Fast Track study is complete, you may apply for the Annual Deliverability Assessment during the Cluster window. This study is performed in coordination with CAISO to allocate any existing available capacity without requiring upgrades.

Are updates performed during the Wholesale Distribution study process?

If the assumptions established at the beginning of your study process change, an updating study may be required to re-evaluate your project’s impact on the distribution system. You are responsible for paying for any such updating study. Examples of changes that might prompt such a study are:

  • Withdrawal of a higher-queued project
  • Change in interconnection date
  • Change in Interconnection Customer’s queue position
  • Change in interconnection plan
  • Change in project’s generating size

After your Scoping Meeting, you can request to have the generating size of your proposed facility adjusted (Changes are acceptable during the Scoping Meeting only for Rule 21.) For information on making modifications after the Scoping Meeting, please refer to Section 1.4 of the Wholesale Distribution Tariff, Attachment I: Generation Interconnection Procedures (GIP) (PDF, 1.5 MB).

Project Locations, Facilities and Rights of Way

Where should I connect?

PG&E's distribution and transmission systems run throughout our service territory. The interconnection site you propose may be near distribution or transmission facilities (60 kV and above is considered PG&E’s transmission system; Southern California Edison’s transmission system voltage is 230 kV and above). PG&E will review and connect your generating facility to your proposed point of interconnection whether that is transmission or distribution. However, it is important to note that it is your responsibility to transform your power to the interconnection voltage level. You should account for the cost of this transformation in your project economics. If you are unclear of what voltage the electric facility nearest to your project site is, please refer to the Solar Photovoltaic (PV) and Renewable Auction Mechanism (RAM) Program Map.

Where are PG&E's substations?

The Solar Photovoltaic (PV) and Renewable Auction Mechanism (RAM) Program Map identifies areas with a circuit voltage of 12 kV or 21 kV and substation capacities that suggest a higher likelihood for successful PV generator interconnection. Each highlighted area contains at least one substation transformer and shows the approximate capacity of the largest transformer. This map is a tool to help PV developers identify potential PV project sites, but it is not a guarantee that generators can interconnect at any particular time and place. Several factors influence whether you can interconnect your PV system to the electric distribution system, including the size of the PV system and substation, circuit load and capability, voltage considerations and how much interconnection will cost. Actual interconnection requirements and costs will be determined following detailed studies that compare your specific project location, size and application date to other projects in the same vicinity. Additionally, government permitting procedures designed to minimize environmental and land use impacts that are independent of our interconnection process may limit the suitability of sites highlighted on this map.

Can PG&E provide the right of way or easement for a third-party line?

PG&E acquires right of ways or easements from land owners for utility purposes only. A third- party line does not qualify for a right of way or an easement because it is not an asset that PG&E owns and maintains, and therefore we cannot assume liability for it.

Can PG&E allow a third-party line to be built on PG&E’s easement or right of way?

PG&E acquires the appropriate amount of land to build transmission lines, distribution lines and substations on a case-by- case basis in compliance with California Public Utility Commission’s (CPUC) General Order 95 (GO95). PG&E typically does not acquire more land than necessary unless expansion needs are present or anticipated. In addition, land owners grant PG&E rights to land for very specific purposes, and we cannot unilaterally extend the rights to another party or make changes without the agreement of the land owner.

Will PG&E build and own my gen-tie?

PG&E considers gen-ties as the Distribution Provider’s Interconnection Facilities, and owns and maintains these facilities at the Interconnection Customer’s expense. These facilities can be engineered and constructed by either the Interconnection Customer or PG&E. PG&E does not own and maintain gen-ties for Generating Facilities connecting to our Wholesale Transmission system, so only the Interconnection Customer can engineer and construct these facilities.

Will PG&E acquire an easement or right of way for gen-ties?

Whether the gen-ties are to be Distribution or Transmission facilities, the Interconnection Customer is responsible for acquiring land rights for their construction. This includes gen-ties that will be built by PG&E for distribution interconnection.

Will PG&E allow me to build on its poles?

No. There are limited circumstances where PG&E may construct, own, and maintain gen-tie lines on PG&E’s poles pursuant to California Public Utility Commission (CPUC) rules and programs. In order to add Wholesale Transmission or Distribution lines to existing poles, we would need to evaluate whether the existing poles can support these new lines in a double-circuit configuration, side by side or on top of each other. The latter configuration would typically require a taller pole in order to maintain GO95 compliance. Regardless of pole replacement or modifications, PG&E is also required by CPUC General Order 131D to submit and request a permit to conduct this work. These requirements can have a significant financial impact on your project.

Types of Interconnection Agreements

What are the different types of interconnection agreements for generators planning to export power to the grid for sale?

There are three types of agreements that detail the terms of such facilities' interconnection with PG&E:

  • CAISO Tariff agreement for Transmission customers (facilities of 60 kV or greater): If you plan to interconnect to the CAISO-controlled grid, you will need to execute either a Large Generator Interconnection Agreement (LGIA) (for facilities larger than 20 MW) or a Small Generator Interconnection Agreement (SGIA) (for facilities smaller than 20 MW). This will be a three-party agreement between you, CAISO and PG&E. Under this agreement, you may select any Power Purchase Agreement, depending on whether you intend to sell power under California Public Utilities Commission (CPUC) or Federal Energy Regulatory Commission (FERC) jurisdiction. If you sign a CAISO Tariff agreement, CAISO will oversee your agreement.
  • If you plan to interconnect to the PG&E-controlled Distribution grid, you need to execute either:
    • A Rule 21 agreement. Depending on the level of study required for your project, this will be either a Fast Track Process or Detailed Study Process interconnection agreement. The agreement will be between you and PG&E. If you sign a Rule 21 agreement, the CPUC will oversee your agreement.
    • A Wholesale Distribution Tariff (WDT) agreement for facilities of less than 60 kV. This will be either a Large Generator Interconnection Agreement (LGIA - for facilities larger than 20 MW) or a Small Generator Interconnection Agreement (SGIA - for facilities smaller than 20 MW) that is a two-party agreement between you and PG&E. If you sign a WDT agreement, the Federal Energy Regulatory Commission (FERC) will oversee your agreement.

For generators interconnecting with PG&E’s distribution grid, the type of agreement you may enter into is determined by the type of Power Purchase Agreement (PPA) you sign:

  • If you sign a PPA other than a Public Utility Regulatory Policy Act (PURPA) PPA, you must execute a Wholesale Distribution Tariff agreement. (An example of a PG&E PURPA PPA is the AB 1613 program.) Otherwise, you may elect to use a WDT agreement in conjunction with any PPA.
  • If you sign a PURPA PPA and interconnect with PG&E’s distribution grid, you are eligible to sign a Rule 21 agreement.

Power Purchase Agreements

How does PG&E purchase power from wholesale generators?

To meet customer load, PG&E purchases wholesale electric energy and capacity from generators and suppliers. PG&E periodically conducts Solicitations/Requests for Offers (RFO) for conventional and renewable electricity in accordance with the Generator Interconnection Procedures (GIP). (The GIP does not constitute an agreement by PG&E to purchase the electric output of the generator.) When we conduct a specific Solicitation/RFO to purchase new energy and/or capacity, we announce the RFO to potential bidders via e-mail and on our website. View information about {PG&E's Wholesale Electric Power Procurement and RFOs >> }

Where can I get more information about PPAs?

Please visit or contact PG&E Energy Procurement.

Gas Service

How do I obtain gas service for my generating facility?

To obtain a transmission pressure (60 psig and greater) natural gas connection for a new generator, review the Gas Generator Connection page. For a new generator that requires distribution pressure (less than 60psig), visit the Building & Renovation Services page.

Qualifying Facilities

What is a Qualifying Facility?

A Qualifying Facility is one that interconnects with PG&E's transmission or distribution system, producing wind, hydroelectric, biomass, waste or geothermal energy. Qualifying facilities can also be cogeneration facilities that produce electricity and another form of thermal energy. Energy deregulation has allowed these generators to choose the markets in which they sell the electricity they generate.

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