Case study: Charging standards & interoperability (NACS, CCS) — a startup-to-enterprise scale story

When Tesla opened its North American Charging Standard (NACS) connector design to the industry in November 2022, fewer than 5% of public non-Tesla DC fast chargers in the United States could serve both CCS1 and NACS vehicles without adapter hardware. By early 2026, more than 60% of new charger deployments include dual-standard or NACS-native connectors, driven by OEM adoption agreements and federal funding requirements under the National Electric Vehicle Infrastructure (NEVI) program (U.S. Department of Energy, 2026). This case study traces how three startups in the EV charging interoperability space navigated the rapid standards transition from CCS dominance to NACS convergence, revealing the product pivots, funding strategies, and regulatory positioning that separated scalable businesses from those caught on the wrong side of an industry inflection point.

Why It Matters

The charging connector standard a vehicle uses determines where it can charge, how fast it can charge, and what it costs to build the infrastructure that serves it. For policy and compliance professionals, the NACS-CCS transition represents one of the fastest standards realignments in modern transportation infrastructure. The Society of Automotive Engineers (SAE) formally adopted Tesla's NACS connector as SAE J3400 in June 2024, and by Q1 2026, every major non-Chinese EV manufacturer selling in North America had announced plans to adopt NACS for new models starting in 2025 or 2026 (SAE International, 2024).

The regulatory stakes are substantial. The NEVI program, funded by $7.5 billion from the Bipartisan Infrastructure Law, initially mandated CCS1 connectors at all federally funded charging stations. Updated guidance from the Federal Highway Administration in late 2024 required at least one NACS connector per station for NEVI compliance, creating a dual-standard mandate that reshaped procurement specifications across all 50 state transportation departments. Charging network operators that had invested exclusively in CCS1 hardware faced retrofit costs estimated at $3,000 to $8,000 per connector, while operators that anticipated the transition gained competitive advantage through lower per-site deployment costs and broader vehicle compatibility (Atlas Public Policy, 2025).

For compliance teams at utilities, fleet operators, and charging network companies, understanding how startups navigated this transition offers practical lessons on technology risk assessment, regulatory anticipation, and infrastructure procurement flexibility.

Key Concepts

NACS (North American Charging Standard) is the connector and communication protocol originally developed by Tesla and opened as a public specification in 2022. NACS uses a smaller, lighter connector than CCS1, supports DC fast charging up to 1 MW, and integrates AC and DC charging in a single plug. SAE standardized it as J3400 in 2024.

CCS (Combined Charging System) combines an AC J1772 plug with two additional DC pins to enable fast charging at rates up to 350 kW. CCS1 is the North American variant and was the dominant DC fast charging standard for non-Tesla EVs from 2014 through 2024. CCS2, used in Europe, uses a Type 2 AC connector base and remains the predominant standard in European markets.

OCPP (Open Charge Point Protocol) is an open communication protocol between charging stations and central management systems. OCPP 2.0.1, released in 2020, supports plug-and-charge authentication, smart charging, and device management. Interoperability between OCPP-compliant stations and multiple network backends is essential for roaming and multi-network access.

Plug-and-charge (ISO 15118) enables automatic authentication and payment when a driver connects their vehicle, eliminating the need for RFID cards or mobile apps. ISO 15118 implementation requires PKI (public key infrastructure) certificates installed in both the vehicle and the charging station, creating an interoperability layer that transcends physical connector standards.

What's Working

ChargePoint: Modular Hardware Strategy Enables Rapid Standard Transition

ChargePoint, founded in 2007 in Campbell, California, had deployed more than 286,000 ports globally by Q4 2025 and was one of the first major charging network operators to announce NACS connector support across its product line. The company's modular hardware architecture, designed with swappable connector cables and updatable power modules, allowed existing CT4000 and Express Plus stations to be retrofitted with NACS cables at a cost of approximately $2,500 per connector, roughly 40% below the industry average retrofit cost.

ChargePoint's enterprise sales team repositioned its fleet charging solution, ChargePoint Fleet, to address the dual-standard challenge facing commercial fleet operators managing mixed vehicle fleets during the 2025 to 2028 transition period. The company's fleet management software was updated to track connector compatibility by vehicle VIN, route chargers based on connector availability, and forecast infrastructure upgrade timelines based on fleet vehicle replacement schedules. By Q1 2026, ChargePoint Fleet served more than 80 enterprise fleet customers operating over 15,000 vehicles across North America, with average contract values exceeding $1.2 million annually (ChargePoint, 2026).

The critical scaling insight from ChargePoint's approach was designing hardware with planned connector obsolescence in mind. The company's Express Plus DC fast charging platform uses a power block architecture where 31.25 kW modules can be combined to deliver up to 500 kW, and connector cables attach via standardized interfaces that accommodate both CCS1 and NACS without replacing the power cabinet. This architectural decision, made in 2019 before the NACS transition was anticipated, gave ChargePoint a 12 to 18 month deployment speed advantage over competitors whose hardware required full cabinet replacements.

FreeWire Technologies: Mobile and Ultrafast Charging for Underserved Sites

FreeWire Technologies, founded in 2014 in Oakland, California, developed battery-integrated charging solutions that combine on-site energy storage with EV charging to serve locations where grid infrastructure cannot support high-power DC fast charging. The company's Boost Charger product line integrates a 160 kWh battery pack with dual DC fast charging dispensers, allowing deployment at sites with as little as 20 kW of available grid capacity while delivering up to 200 kW of charging power to vehicles.

FreeWire raised $165 million in total funding through Series C, with investors including BP Ventures, Riverstone Holdings, and Uber. The company's pivot from workplace Level 2 charging (its original 2014 product) to battery-integrated ultrafast charging in 2020 illustrates how startups in the charging space must adapt product strategy to market inflection points. When NACS adoption accelerated in 2024, FreeWire's battery-integrated architecture provided a natural advantage: adding a NACS connector to a Boost Charger unit required only a cable and firmware update, with no changes to the battery or power electronics subsystems.

By 2025, FreeWire had deployed more than 500 Boost Charger units across convenience store chains, parking garages, and retail locations in 38 states. The company's site acquisition cost averaged $45,000 below traditional DC fast charging installations because grid upgrade requirements were eliminated. For sites in rural and suburban areas eligible for NEVI funding, FreeWire's technology addressed the critical bottleneck of inadequate utility infrastructure, enabling compliant deployments in locations where traditional 150 kW to 350 kW chargers would require $100,000 to $500,000 in utility service upgrades (FreeWire Technologies, 2025).

Hubject: Interoperability Platform Scaling Across Network Boundaries

Hubject, founded in Berlin in 2012 as a joint venture between BMW, Bosch, Daimler, EnBW, Innogy, and Siemens, operates the intercharge network, which connects more than 600,000 charging points across 62 countries through a roaming platform. In North America, Hubject's platform gained traction as the NACS transition created new interoperability complexity: drivers needed to access charging stations across multiple networks regardless of connector type, payment method, or network membership.

Hubject's ISO 15118 Plug&Charge ecosystem, launched in 2021, became the foundation for automated authentication across connector standards. By Q1 2026, 14 OEMs and 23 charging network operators in North America had enrolled in Hubject's Plug&Charge certificate management system. The platform processes more than 3 million roaming transactions per month in North America, with transaction volumes growing 140% year-over-year since 2024 (Hubject, 2026).

The company's enterprise sales cycle in North America shortened from an average of 14 months in 2022 to 7 months in 2025, driven by regulatory pressure. NEVI compliance requirements for interoperability and payment accessibility created a compliance deadline that forced charging network operators to adopt roaming solutions. Hubject's pricing model, based on a per-transaction roaming fee of $0.08 to $0.15 rather than upfront licensing costs, reduced adoption barriers for smaller regional charging networks that lacked the engineering resources to build bilateral roaming agreements with each major network.

What's Not Working

Stranded CCS-only infrastructure represents a growing financial liability for early movers who deployed large CCS1-only networks between 2020 and 2023. Electrify America, the largest non-Tesla DC fast charging network in the U.S., disclosed retrofit costs of approximately $250 million to add NACS connectors across its 3,500-plus station network. Smaller regional operators face proportionally higher per-station costs because they lack the procurement volume to negotiate favorable connector and cable pricing, with some operators reporting per-connector retrofit costs exceeding $10,000 (Bloomberg NEF, 2025).

Plug-and-charge adoption gaps undermine the seamless experience that interoperability platforms promise. While 14 OEMs support ISO 15118 Plug&Charge in their newest models, older EV models (representing approximately 70% of the current U.S. EV fleet) require RFID cards, mobile apps, or credit card readers for authentication. This creates a bifurcated user experience where the same charging station delivers frictionless authentication for some vehicles and error-prone manual authentication for others. Charging network operators report that 12 to 18% of customer complaints relate to authentication failures at dual-standard stations (J.D. Power, 2025).

Utility interconnection delays continue to constrain deployment timelines regardless of connector standard. The average time from site selection to energized charger for a new DC fast charging station in the U.S. is 22 months, with utility interconnection accounting for 12 to 16 months of that timeline. NEVI-funded projects face additional procurement and environmental review requirements that add 3 to 6 months. Startups with innovative hardware solutions find that their deployment speed advantage is negated by utility permitting backlogs that apply equally to all equipment types.

Cybersecurity vulnerabilities at dual-standard stations have emerged as a compliance concern. Stations supporting both NACS and CCS1 connectors with OCPP 2.0.1 backend communication create a larger attack surface than single-standard systems. NIST published updated cybersecurity guidelines for EV charging infrastructure in 2025, and several state public utility commissions now require cybersecurity audits as a condition of rate-based charging infrastructure approval. Compliance costs for cybersecurity certification add $1,500 to $4,000 per station, a meaningful expense for operators managing hundreds of locations.

Key Players

Established Companies

• ChargePoint: largest publicly traded EV charging network company, operating 286,000-plus ports with modular dual-standard hardware
• Electrify America: Volkswagen-funded network with 3,500-plus stations undergoing NACS retrofit across the U.S.
• Tesla Supercharger: operates 30,000-plus NACS connectors in North America, opened network to non-Tesla vehicles starting in 2024

Startups

• FreeWire Technologies: battery-integrated ultrafast charging eliminating grid upgrade requirements, deployed in 38 states
• Hubject: interoperability and roaming platform connecting 600,000-plus charging points with ISO 15118 Plug&Charge ecosystem
• Ampcontrol: AI-powered charging optimization software managing power distribution across multi-connector stations
• EVPassport: white-label charging management platform enabling property owners to operate branded multi-standard charging networks
• AmpUp: cloud-based charging management and energy optimization platform serving commercial and multifamily residential deployments

Investors and Funders

• BP Ventures: lead investor in FreeWire Technologies across multiple funding rounds
• Siemens Financial Services: infrastructure financing for charging network deployments across North America
• BlackRock Climate Infrastructure: large-scale capital deployment into charging network buildout and grid interconnection projects

Action Checklist

• Audit current charging infrastructure for connector standard compatibility, documenting CCS-only stations that require NACS retrofit and estimating per-station conversion costs
• Review NEVI compliance requirements in your state's EV infrastructure deployment plan, noting dual-standard mandates and interoperability requirements
• Evaluate charging hardware vendors' modular upgrade capabilities before procurement, requesting documentation of connector swap procedures, firmware update processes, and warranty coverage for retrofitted equipment
• Require OCPP 2.0.1 compliance and ISO 15118 Plug&Charge support in all new charging equipment procurement specifications
• Develop fleet vehicle connector transition timelines mapping vehicle replacement schedules against charging infrastructure upgrade plans
• Establish interoperability agreements with at least two roaming networks to ensure driver access across network boundaries
• Include cybersecurity audit requirements in charging infrastructure procurement contracts, referencing NIST EV charging security guidelines

FAQ

Q: What is the typical cost to retrofit a CCS1-only DC fast charger with a NACS connector? A: Retrofit costs range from $2,500 to $10,000 per connector depending on the charger hardware architecture. Modular systems designed with swappable connector cables, such as ChargePoint's Express Plus and ABB's Terra series, fall at the lower end. Older integrated designs that require power electronics modifications or full dispenser replacement cost $7,000 to $10,000 per connector. These estimates include parts, labor, and firmware updates but exclude any utility work. Operators managing more than 100 stations can typically negotiate volume pricing 15 to 25% below list rates.

Q: How long does it take a charging startup to reach enterprise-scale operations? A: Hardware-focused charging startups like FreeWire typically require 5 to 7 years from founding to enterprise scale (defined as more than 500 deployed units generating more than $50 million in annual revenue), with capital requirements of $100 million to $200 million through Series C or project finance. Software and platform startups like Hubject and AmpUp can reach enterprise scale (50-plus enterprise clients, 100,000-plus connected ports) within 3 to 5 years with $30 million to $80 million in funding. The critical bottleneck for hardware companies is manufacturing scale-up and site deployment, while software companies face longer enterprise sales cycles but lower capital intensity.

Q: Will CCS connectors become obsolete in North America? A: CCS1 will remain relevant in North America through at least 2032. Approximately 4.5 million CCS-equipped EVs are projected to be on U.S. roads by 2030, and those vehicles will need charging infrastructure throughout their 10 to 15 year lifespan. Federal NEVI guidelines require funded stations to include at least one CCS1 connector alongside NACS. However, new vehicle production is shifting decisively to NACS: by 2027, more than 90% of new EV models sold in North America will use NACS natively. The transition period creates a dual-standard infrastructure requirement that will persist for approximately 8 to 10 years.

Q: What interoperability standards should compliance teams prioritize? A: Prioritize OCPP 2.0.1 for station-to-network communication, ISO 15118 for Plug&Charge authentication, and OpenADR 2.0 for demand response integration with utilities. For roaming, ensure your network operator participates in at least one major roaming platform (Hubject intercharge or OCPI-based bilateral agreements). NEVI compliance requires contactless payment (at minimum EMV credit card readers) and real-time availability data sharing via API. State-level requirements vary, so review your state's EV infrastructure deployment plan for additional interoperability mandates.

Sources

• U.S. Department of Energy. (2026). Alternative Fueling Station Locator: EV Charging Infrastructure Deployment Tracker. Washington, DC: DOE Office of Energy Efficiency and Renewable Energy.
• SAE International. (2024). SAE J3400: North American Charging Standard (NACS) Connector Specification. Warrendale, PA: SAE International.
• Atlas Public Policy. (2025). EV Charging Infrastructure Policy Dashboard: Federal and State Compliance Requirements. Washington, DC: Atlas Public Policy.
• ChargePoint Holdings. (2026). Q4 2025 Earnings Report: Fleet Charging and Network Expansion. Campbell, CA: ChargePoint Holdings Inc.
• FreeWire Technologies. (2025). Battery-Integrated Charging Deployment Report: Site Economics and Grid Impact Analysis. Oakland, CA: FreeWire Technologies Inc.
• Hubject GmbH. (2026). North American Interoperability and Roaming: Annual Market Report. Berlin: Hubject GmbH.
• Bloomberg New Energy Finance. (2025). EV Charging Equipment Cost Survey: Retrofit Economics and Dual-Standard Deployment. New York, NY: Bloomberg LP.
• J.D. Power. (2025). U.S. Electric Vehicle Experience Public Charging Study. Troy, MI: J.D. Power.