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South Carolina (US-SC)

Market Type: Hybrid (Limited Retail Choice)
SSS Relevance: ⭐⭐⭐ High
Grid Carbon Intensity: See emissions section

SSS Factors: significant nuclear capacity, hydroelectric resources, no mandatory RPS, regulated market structure

1. Overview​

South Carolina's electricity market is characterized by a vertically integrated monopoly structure where single utilities own generation, transmission, and distribution assets 1. Rates and operations are regulated by the South Carolina Public Service Commission (PSC), and the state currently lacks a regional wholesale market, though some utilities participate in the Southeast Energy Exchange Market (SEEM) 1.

The state's generation mix is heavily reliant on nuclear power, which accounts for approximately 55% to 60% of total electricity, making South Carolina one of the top low-carbon energy producers in the nation 23. As of early 2026, the remaining generation mix consists of Natural Gas (~15%–23%), Coal (~17%–18%), and Renewables (~5.4%–6.9%) 43. Within the renewable sector, solar is the fastest-growing source (2.9%–4%), followed by hydroelectric power (2.3%–2.4%) and minor contributions from biomass (0.1%) 5.

Due to its significant nuclear capacity, South Carolina maintains a low carbon intensity of approximately 266 gCO2eq/kWh, which is below the national average 6. About 60% of the state's electricity comes from low-carbon sources 3. ⚠️ Recent data indicates rising demand driven by population growth and energy-intensive industries, alongside rising retail prices; as of March 2026, residential rates were approximately 15.71¢/kWh, representing a 3.6% increase over the previous year, with a pending 12.7% rate hike requested by Dominion Energy for July 2026 7.

Legislators are exploring market modernization paths, including the creation of an Energy Imbalance Market (EIM), Limited Retail Choice (LRC) for large industrial consumers, and the potential for a Regional Transmission Organization (RTO) 11.

2. Market Structure​

As of March 2026, South Carolina maintains a regulated electricity market characterized by vertically integrated utilities that control generation, transmission, and distribution within assigned territories. Consequently, there is no residential retail choice, meaning residents cannot shop for alternative electricity providers 1. The market is divided among investor-owned utilities (IOUs), electric cooperatives, and municipal systems, with no participation in a Regional Transmission Organization (RTO) or Independent System Operator (ISO) 3.

Utility Ownership​

The state's utility landscape comprises four primary categories:

  • Investor-Owned Utilities (IOUs): Regulated by the South Carolina Public Service Commission (PSC), major providers include Dominion Energy South Carolina, Duke Energy Carolinas, Duke Energy Progress, and Lockhart Power Company 8 9.
  • Electric Cooperatives: 19 independent distribution cooperatives serve over 2 million residents across all 46 counties. These are supported by Central Electric Power Cooperative, a wholesale generation and transmission cooperative 10.
  • Municipal Utilities: 21 cities operate their own public power systems, such as Rock Hill and Greer. The Piedmont Municipal Power Agency (PMPA) provides wholesale power to 10 of these municipal systems 11.
  • State-Owned Utility: Santee Cooper (South Carolina Public Service Authority) serves retail customers directly and provides wholesale power to the 20 electric cooperatives via Central Electric Power Cooperative 11.

Wholesale Market and Grid Management​

South Carolina does not currently utilize an organized wholesale electricity market or belong to an RTO/ISO 12. Instead, utilities coordinate through the South Carolina Regional Transmission Planning (SCRTP) process to ensure reliability 13. However, legislative efforts such as S 909 have explored implementing an Energy Imbalance Market (EIM) by 2028 to introduce competition, potentially saving customers hundreds of millions annually 13.

Recent Legislative Developments​

The market structure is subject to ongoing debate regarding restructuring and security:

  • South Carolina Energy Security Act (Act 41): Passed in May 2025, this law prioritizes "energy security" over deregulation, streamlining permitting for new power plants (e.g., a proposed 2,000-megawatt natural gas plant in Colleton County) and allowing for annual rate adjustments to cover infrastructure costs.
  • Limited Retail Choice (LRC): As of early 2026, a coalition including the Palmetto Industrial Energy Association (PIEA) is advocating for LRC, though broad deregulation has not been enacted. While natural gas operates under a limited choice system for large users, electric retail choice remains largely restricted to very high-volume commercial and industrial users 1.

3. Clean Energy Policy​

South Carolina does not have a mandatory Renewable Portfolio Standard (RPS) or a statewide clean energy mandate. Instead, the state relies on voluntary goals and legislative frameworks to encourage renewable energy development [1][2].

Voluntary Renewable Goals Established by Senate Bill 1189 in 2014, the Distributed Energy Resource Program set a voluntary goal for renewable energy to reach 2% of aggregate generation capacity by 2021. This target was split into specific carve-outs:

  • Small-scale facilities (<1 MW): 1% of aggregate generation capacity (with at least 0.25% from residential systems under 20 kW).
  • Large-scale facilities (1–10 MW): 1% of aggregate generation capacity [1].

Major utilities, such as Duke Energy Carolinas, successfully met this 2% goal. Following this achievement, utilities are permitted to continue investing in renewable facilities (1–10 MW) with cumulative capacity up to 1% of their previous five-year retail peak demand average. This voluntary standard applies specifically to Investor-Owned Utilities (IOUs) [1].

Key Legislation

  • SC Energy Freedom Act (Act 62 of 2019): A landmark bill that significantly expanded the state's solar market [2].
  • SC Energy Security Act (Act 41 of 2025): Signed in May 2025, this legislation aims to meet growing energy demand from data centers and manufacturing. It authorizes a 2,000 MW natural gas plant at the former Canadys Station site, streamlines environmental reviews for gas pipelines, and expands nuclear capacity [2][3].

Utility and Local Decarbonization Targets While there is no state-level mandate for net-zero emissions, major utilities and municipalities have set their own targets:

  • Duke Energy: Aims for net-zero carbon emissions by 2050, with interim targets of a 50% reduction by 2030 and 70% reduction for Carolinas operations by 2030 [3].
  • Dominion Energy: Committed to net-zero greenhouse gas emissions by 2050 [3].
  • Local Governments: Charleston County aims for net-zero by 2050, the City of Charleston targets an 80% reduction in GHG emissions by 2050, and the City of Columbia aims for 100% renewable energy by 2036 [2][3].

Electricity Mix As of 2024/2025, South Carolina's electricity mix is approximately 60% low-carbon (primarily nuclear at >50% and solar at ~4%) and 40% fossil fuels (natural gas at ~22% and coal at ~18%) [3].

4. Utility Landscape​

South Carolina’s electric utility landscape is a mix of state-owned, investor-owned, and consumer-owned entities serving approximately 2.5 million customers 14. The state features four regulated investor-owned utilities (IOUs) overseen by the South Carolina Public Service Commission (PSC) and the Office of Regulatory Staff (ORS) 15. The primary IOUs include Dominion Energy South Carolina, Duke Energy Carolinas, Duke Energy Progress, and Lockhart Power Company 15. These entities are vertically integrated and serve over half of the state's electricity customers 15. Additionally, Santee Cooper (South Carolina Public Service Authority) operates as a major state-owned public utility rather than an IOU 15.

Consumer-owned providers serve approximately two-thirds of the state's land area 16. This sector comprises 20 electric distribution cooperatives, which serve 1.5 million people across all 46 counties and operate over 74,000 miles of power lines 10. Most cooperatives purchase wholesale power collectively through Central Electric Power Cooperative, sourcing from Santee Cooper, Duke Energy, and Dominion Energy. Municipal utilities, owned by local city governments, typically serve urban centers and often operate as Commissions of Public Works (CPW) 10.

5. SSS-Eligible Resources​

No specific SSS-eligible resources identified. See section notes.

6. EAC/REC Registry Infrastructure​

South Carolina does not operate a dedicated, state-specific Renewable Energy Certificate (REC) registry. Instead, the state relies on regional and national tracking systems to issue, transfer, and retire Energy Attribute Certificates (EACs) 17.

Primary Tracking Systems​

  • NC-RETS (North Carolina Renewable Energy Tracking System): This is the dominant regional registry utilized by major South Carolina utilities, such as Duke Energy, to manage RECs for both compliance and voluntary programs 17.
  • NAR (North American Renewables Registry): NAR serves as a default registry for generators in South Carolina that do not utilize NC-RETS, accepting projects from across the U.S. and Canada 18.

Secondary and Regional Systems​

  • M-RETS (Midwest Renewable Energy Tracking System): Although regional in origin, M-RETS accepts generators from anywhere in the U.S. and facilitates voluntary REC transactions involving South Carolina resources 18.
  • PJM-GATS (Generation Attribute Tracking System): While South Carolina is located outside the PJM Interconnection region, RECs from South Carolina generators can be exported to PJM-GATS if the generator is serving load within a PJM state that allows imports 18.
  • WREGIS (Western Renewable Energy Generation Information System): This system is generally not used for South Carolina RECs unless specific bilateral contracts require transfers to the Western market 18.

Operational Mechanisms​

  • Issuance and Tracking: For every 1 megawatt-hour (MWh) of renewable energy generated, tracking systems assign a unique serial number to create a REC. This process prevents double-counting by ensuring a certificate is only retired once 17.
  • Market Split: Most South Carolina RECs are traded in the voluntary market. However, certificates can be used for compliance in other states provided the generator meets that state's specific eligibility criteria 18.

State Oversight​

While the state does not manage a registry, the South Carolina Office of Regulatory Staff (ORS) oversees related certifications, such as the certification of companies leasing renewable energy facilities 19. Additionally, the South Carolina Energy Office administers certification for state solar energy system tax credits 19.

7. Grid Emissions​

Generation Mix​

Source: EPA eGRID, EIA, state regulatory filings

References​

Sources & Last Updated​

Research Date: 2026-03-10
Data Sources: EIA, EPA eGRID, state regulatory filings, SerpAPI research aggregation

This page was generated using automated research and may contain inaccuracies. Verify critical data with primary sources.

Footnotes​

  1. Palmetto Promise Institute ↩ ↩2 ↩3 ↩4 ↩5 ↩6

  2. EBSCO ↩

  3. U.S. Energy Information Administration (EIA) (.gov) ↩ ↩2 ↩3 ↩4

  4. America’s Health Rankings ↩

  5. Solar Energy Industries Association ↩

  6. Low-Carbon Power ↩

  7. Electric Choice ↩

  8. Southeast Energy Alliance ↩

  9. SC Energy Saver (.gov) ↩

  10. Electric Cooperatives of South Carolina ↩ ↩2 ↩3

  11. Santee Cooper ↩ ↩2

  12. Energy Star (.gov) ↩

  13. Federal Energy Regulatory Commission (.gov) ↩ ↩2

  14. Search Results ↩

  15. Southeast Energy Efficiency Alliance ↩ ↩2 ↩3 ↩4

  16. South Carolina Power Team ↩

  17. U.S. Environmental Protection Agency (.gov) ↩ ↩2 ↩3

  18. resource-solutions.org ↩ ↩2 ↩3 ↩4 ↩5

  19. South Carolina State Government (.gov) ↩ ↩2