Interconnection Guidelines

June 07, 2024

Summary

The South Carolina Public Service Commission (PSC) adopted simplified interconnection guidelines for small distributed generation (DG) in December 2006.  South Carolina's interconnection guidelines apply to Duke Energy Progress, Duke Energy Carolinas, and Dominion Energy. These guidelines address interconnection of renewable- energy systems and other forms of DG in three levels -

  1. Streamlined interconnection process for a certified inverter based generating unit up to 20 kW
  2. Fast Track for interconnection for systems larger than 20 kW up to 2 MW
  3. For larger interconnection systems greater than 2 MW requiring interconnection study.

The customer may submit a formal Pre-Application Report request with a $500 non-refundable fee. The utility will provide a report identifying the substation, area bus, or a circuit that would be the proposed point of interconnection. 

Utilities may not require residential customers to carry liability insurance beyond the amount required by a standard homeowner's policy ($100,000 minimum coverage), but non-residential generators are required to carry comprehensive general liability insurance ($300,000 minimum coverage). Generators are responsible only for upgrade and improvement costs associated directly with a system's interconnection, but these costs may be determined by utilities. Utilities are prohibited from imposing indirect fees and charges. The guidelines include a mutual-indemnification requirement.


A redundant external disconnect switch is required, and the capacity of all interconnected generation is generally limited to a maximum of 2% of rated circuit capacity.

Program Overview

Implementing Sector: State
Category: Regulatory Policy
State: South Carolina
Incentive Type: Interconnection
Web Site: https://solar.sc.gov/installing-and-maintaining-system/working-utilities/interconnection
Administrator:
Start Date:
Eligible Renewable/Other Technologies:
  • Solar Thermal Electric
  • Solar Photovoltaics
  • Wind (All)
  • Biomass
  • Municipal Solid Waste
  • Combined Heat & Power
  • Fuel Cells using Non-Renewable Fuels
  • Landfill Gas
  • Wind (Small)
  • Hydroelectric (Small)
  • Anaerobic Digestion
  • Fuel Cells using Renewable Fuels
  • Other Distributed Generation Technologies
  • Microturbines
Applicable Utilities: Investor-owned utilities
System Capacity Limit: 20 kW for residential;
Fast track interconnection for certified inverter based generation up to 1MW regardless of location, and fast track up to 2 MW for interconnection to higher voltage distribution line and located less than 2.5 miles from nearest substation.
Other systems require system impact study for interconnection.
Standard Agreement: Yes
Insurance Requirements: Residential : Standard homeowner's insurance policy with liability coverage of at least $100,000 per occurrence.
Non-Residential: for size less than 20 kW- liability coverage up to $300,000
External Disconnect Switch: Required
Net Metering Required: No

Authorities

Name: PSC Order, Docket No. 2005-387-E
Date Enacted: 12/19/2006
Name: PSC Order, Docket No. 2015-362-E
Date Enacted: 04/26/2016

Contact

Name: Office of Regulatory Staff
Organization: Energy Office
Address: 1401 Main Street, Suite 900
Columbia SC 29201
Phone: (803) 737-0800

This information is sourced from DSIRE; the most comprehensive source of information on incentives and policies that support renewables and energy efficiency in the United States. Established in 1995, DSIRE is operated by the N.C. Clean Energy Technology Center at N.C. State University.