Interconnection Standards for Small Generators

NOTE: In July 2016, FERC issued Order 828 revising the Small Generation Interconnection Agreement (SGIA) to require newly interconnecting small generators under 20 MW to ride through abnormal frequency and voltage events and not be disconnected during such events. 

Origin

Through its Orders 792 and 792-A, the Federal Energy Regulatory Commission (FERC) adopted new "small generator" interconnection standards for distributed energy resources up to 20 megawatts (MW) in capacity in November 2013 and September 2014, respectively. These standards made revisions to those promulgated by FERC in May 2005 through its Order 2006. The FERC's standards apply only to facilities subject to the jurisdiction of the commission; these facilities mostly include those that interconnect at the transmission level. Given that purely intra-state distribution grids are generally considered to not be in "interstate commerce", the FERC's standards generally do not apply to distribution-level interconnection, which is regulated by state public utilities commissions. However, FERC's standard tends to serve as a guidepost for a number of state-level standards.

Small Generator Interconnection Procedures and Agreement (SGIP & SGIA)

The FERC's standards include Small Generator Interconnection Procedures (SGIP) and a Small Generator Interconnection Agreement (SGIA). The SGIP contains the technical procedures that the small generator and utility must follow in the course of connecting the generator with the utility's lines. The SGIA contains the contractual provisions for the interconnection and spells out who pays for improvements to the utility's electric system (if needed to complete the interconnection).

Applicable SGIP/SGIA Interconnection Review Processes

The standards include provisions for three levels of interconnection:

• The "10-kilowatt (kW) Inverter Process"; 
  
• The "Fast Track Process"; and 
  
• The default "Study Process," for all other systems.

The tables below describes the different "breakpoints," or the various system sizes at which the different processes would apply. The first table is an overall table comparing the breakpoints between the two FERC orders, .

Standard of Review	Previous Rule (FERC Order 2006)	New Rule (FERC Order 792)
10 kW Inverter Process	Up to 10 kW	Up to 10 kW
Fast-Track Process	10 kW through 2,000 kW (2 MW)	Voltage-Differentiated (See Table Below)
Study Process	2 MW through 20 MW	through 20 MW
≥ 30 kV and ≤ 69 kV	2 MW	4 MW

The table below is a detailed breakdown of the voltage-differentiated breakpoints for the newly-adopted "fast track" process newly adopted in Order 792.
 

Applicable Delivery System Voltage Levels for Fast Track Process (FERC Order 792)	Applicable System Size (Regardless of Location)	Applicable System Size (Location-Specific*)
< 5 kilovolt (kV)	500 kW	500 kW
≥ 5 kV and < 15 kV	2 MW	3 MW
≥ 15 kV and < 30 kV	3 MW	4 MW
≥ 30 kV and ≤ 69 kV	4 MW	5 MW

The standards include technical screens for each level of interconnection. Notably, the FERC standards do not require systems to include an external disconnect switch. Utilities and customers must follow specific timelines, and guidelines for interconnection and study fees are established. Customers must obtain liability insurance "sufficient to insure against all reasonably foreseeable direct liabilities given the size and nature of the generating equipment being interconnected, the interconnection itself, and the characteristics of the system to which the interconnection is made." Additional liability insurance must be obtained "only if necessary as a function of owning and operating a generating facility."

Other New Provisions in Order 792 & 792-A (2013 & 2014)

The new rules include other additional provisions intended to promote the efficiency of small generator interconnection, including, but not limited to:

• Allowing developers/customers to request a pre-application report that would allow for identification of issues that may delay or halt the interconnection process that must be issued within 20 days;
• Revising the Fast Track process to ensure that the developer/customer does not wait more than 5 days for an initial determination, more than 30 days for a "supplemental study" if the initial determination is negative, or more than 10 days after a post-"supplemental study" determination; 
• The creation of three new standard technical screens for the "supplemental study"; and 
• Allowing energy storage systems to qualify for interconnection under the SGIP process (assuming the SGIP process applies. 

For a detailed look at each and every change to the SGIP/SGIA resulting from Orders 792 & 792-A, please visit FERC's SGIP/SGIA website to view red-lined copies of each.

In July 2016, FERC issued Order 828 revising the Small Generation Interconnection Agreement (SGIA) to require newly interconnecting small generators under 20 MW to ride through abnormal frequency and voltage events and not be disconnected during such events. This ride through requires the small generating facility to stay connected to and be synchronized with the transmission system during system disturbances within a range of over and under frequency/ voltage conditions as comparable to large generating facilities.  

In February 2018, FERC issued Order 842, requiring newly interconnecting large and small generating facilities, both synchronous and non-synchronous, to install, maintain, and operate equipment capable of providing primary frequency response as a condition of interconnection.

In July 2023, FERC adopted Order 2023, adopting numerous reforms to interconnection processes designed to manage the interconnection queue in a more timely fashion, including adopting a first-ready, first-served cluster study process. FERC clarified this order with Order 2023-A in March 2024.

* FERC Order 792 allows larger systems to interconnect under the Fast Track process if the system is on a "mainline" and less than 2.5 electrical circuit miles (CM) from a substation. In the order, FERC defines a "mainline" to be "the three-phase backbone of a circuit" that will "typically constitute lines with wire sizes of 4/0 American wire gauge, 336.4 kcmil, 397.5 kcmil, 477 kcmil and 795 kcmil." The requirement that utilities provide developers of interconnecting systems with a pre-application report also requires that the distance to the substation be provided in that report.