Comparison of Grid-Tied ESS & EV Charging Standards: Korea vs. USA

1. Electrical Grid Standards & Interconnection

• Korea: Operates on 220V AC, 60Hz for residential power. Grid-tied ESS follows KEPCO (Korea Electric Power Corporation) standards, which focus on frequency stability and energy efficiency.

• USA: Uses 120V/240V AC, 60Hz for residential and UL 1741 & IEEE 1547 standards for grid-tied ESS interconnection, ensuring anti-islanding protections and grid safety.

2. EV Charging Standards & Protocols

• Korea:

  • Chaevi (Korean CCS2) and CHAdeMO for DC fast charging.

  • J1772 (Type 1) for AC charging, similar to the U.S.

• USA:

  • CCS1 (Combined Charging System) is the dominant fast-charging standard.

  • Tesla's NACS (North American Charging Standard) is being adopted by more OEMs.

3. Compliance & Safety Standards

• Korea:

  • KC (Korea Certification) and KESCO (Korea Electrical Safety Corporation) regulate ESS and EV charging safety.

  • KEPRI (Korea Electric Power Research Institute) oversees grid-tied system approvals.

• USA:

  • UL 1973 for battery safety, UL 1741 for inverters, IEEE 1547 for grid interconnection.

  • NEC (National Electrical Code) mandates installation safety requirements.

4. Energy Storage Regulations

• Korea:

  • Government-backed ESS incentives and mandates, focusing on renewable energy integration.

  • Fire safety is a growing concern, leading to enhanced battery thermal runaway testing after past ESS incidents.

• USA:

  • Stricter fire safety regulations (UL 9540, NFPA 855) due to thermal runaway risks.

  • Cybersecurity & grid stability compliance (NERC CIP, NIST) is a key factor in ESS deployments.

Key Takeaways for OEMs & ESS Developers

✅ Grid interconnection is stricter in the U.S., requiring additional safety and anti-islanding measures.

✅ EV charging connectors & communication protocols differ, requiring adaptations for each market.

✅ U.S. fire safety and cybersecurity standards are more stringent, affecting ESS design and testing requirements.

Looking to expand your ESS or EV charging products to the U.S.?

Eternal Lotus specializes in compliance strategy, testing, and certification to help you enter the market smoothly. Let’s connect!