EV Charging for Commercial Premises: Workplace, Retail and Fleet Installation

Summary

Commercial EV charging covers a wide spectrum: a small business installing two chargepoints in a car park to a logistics depot installing 50 chargepoints for overnight fleet charging. The principles are the same as domestic — BS 7671 Chapter 722 compliance, smart charging, PME earthing resolution — but the scale adds complexity in supply capacity, load management, network connectivity, and commercial management.

For electricians, commercial EV charging is a significant revenue opportunity. A 10-chargepoint installation for a commercial car park is a medium-sized commercial electrical project. Skills required: load assessment, three-phase distribution, cable management, DNO engagement, and chargepoint network commissioning. Understanding the OZEV funding landscape is also valuable — clients often don't know what grants are available.

Key Facts

• OZEV EV Infrastructure Grant — grants for businesses and public sector: up to £350 per socket, max 40 sockets (previously 30); not means-tested; requires OZEV-authorised installer
• OZEV Workplace Charging Scheme (WCS) — now replaced by/merged into the EV Infrastructure Grant for most applications; check current OZEV guidance
• EV Infrastructure Grant — covers both socket installation and associated electrical infrastructure upgrades (consumer unit upgrades, supply upgrades); broader than the old WCS
• DNO notification — any installation exceeding the DNO's informal threshold (typically 50kW+ or multiple chargepoints) should be notified to the DNO; G99 connection application may be required for larger sites
• Network management system (CPMS) — Charge Point Management System; allows remote monitoring, user authentication (RFID, app), payment processing, and usage reporting; essential for public-facing or shared workplace chargepoints
• OCPP (Open Charge Point Protocol) — the open standard enabling chargepoints from different manufacturers to communicate with a CPMS; always specify OCPP-compatible chargepoints for commercial installations
• Type 2 socket — standard for commercial chargepoints (untethered); customers use their own cables; preferred where multiple vehicle types will be charged
• Tethered Type 2 — preferred for fleet vehicles of known type; reduces driver error
• 22kW three-phase — common for commercial car parks; charges most vehicles in 1–2 hours
• 7kW single-phase — still common for workplace chargepoints where overnight charging is acceptable
• Load balancing — critical for multi-chargepoint sites; dynamic load balancing allocates available supply current between active chargepoints
• Time-of-use tariffs — smart commercial chargepoints can schedule charging to off-peak electricity times; significant cost saving for large fleets
• Authorisation and billing — commercial chargepoints typically require RFID, app, or contactless payment; public-facing chargepoints must offer contactless payment under the PAS 1899 standard (for new installations from 2024)

Quick Reference Table: Commercial EV Charging Scenarios

Detailed Guidance

Site Survey for a Commercial Installation

A commercial site survey goes beyond domestic:

Supply capacity assessment:

• Confirm the supply voltage and phases (most commercial is three-phase 400V)
• Read the supply capacity from the DNO cut-out — typically 63A, 100A, 125A, or 200A per phase for commercial
• Estimate standing load (HVAC, lighting, machinery) — ideally from energy bills or measured data
• Calculate available headroom for EV charging: (supply rating × 3 phases × 230V) minus standing load = available kW

Example: 100A three-phase supply = 100A × 400V × √3 = ~69kW total capacity. Standing load 20kW. Available headroom ~49kW. At 7.4kW per chargepoint, that supports ~6 simultaneous full-rate chargepoints; with load management, more chargepoints can be installed that share the headroom.

Physical routing:

• Map the route from the distribution board to each chargepoint location
• Note cable distances, existing trunking, duct crossings, car park surfacing
• Identify any third-party land affected (boundary issues, landlord consent)

Parking layout:

• Consider bollard-mounted vs wall-mounted vs pedestal chargepoints
• Cable sweep areas (vehicles reversing into bays)
• Disabled bay accessibility (chargepoints serving accessible bays must be at accessible height)

Load Management for Multiple Chargepoints

With 10+ chargepoints on a shared supply, dynamic load management is essential:

CT clamp gateway: A central gateway (e.g., Wallbox Commander, Schneider EVlink Pro, Zaptec Gateway) connects to CT clamps on the main incomer and to all chargepoints via Ethernet or Wi-Fi. It monitors total site load and allocates available current to each chargepoint in real time.

Allocation strategies:

• Equal sharing: available current divided equally among all active chargepoints; simplest but inefficient if only one vehicle is charging
• First-come priority: first vehicle connected gets maximum current; later arrivals share remainder
• Scheduled charging: chargepoints hold during peak tariff hours; release full power during off-peak (common for fleet depots to minimise energy costs)
• Priority groups: management vehicles or certain bays get guaranteed minimum charge rates; others share the remainder

Infrastructure sizing for load management: The cable from the distribution board to each chargepoint must still be sized for the maximum possible current to that chargepoint (32A per chargepoint even if load management will often reduce this), unless a sub-distribution board with a smaller fuse serves groups of chargepoints. Alternatively, a sub-board with a 63A or 100A three-phase feed can serve 6–12 chargepoints with load management, reducing the cable size required to each chargepoint from the main distribution board.

DNO Engagement

For commercial installations, DNO engagement is often required:

When to notify:

• Total new EV load exceeding approximately 50kW (varies by DNO — check their published threshold)
• Any installation requiring a supply upgrade
• Three-phase supply where not already present
• Battery storage systems combined with EV charging (bidirectional/V2G)

Application process (G99/G100 for generation; ENA framework for load): Most EV charging loads are "demand" (not generation), so G99/G100 technically doesn't apply. However, large EV loads may require a "demand increase application" via the DNO's standard connection process. Contact the DNO's connections team with the proposed load (kW, phases, address) and they will advise whether a formal application is required.

Supply upgrade: Where the existing supply is insufficient, the DNO will quote for an upgrade (new service cable from the nearest substation or transformer upgrade). This can cost £5,000–£50,000+ and take 6–18 months. Factor this into project timelines and budgets.

OCPP and Charge Point Management Systems

For any installation with public access, multi-user access, or billing requirements:

OCPP (Open Charge Point Protocol): Specify OCPP 1.6 or 2.0.1 compliant chargepoints. This allows the chargepoint to connect to any OCPP-compatible back-office system (CPMS). Avoid proprietary-only chargepoints that lock the customer into a single network operator.

CPMS selection: The CPMS provides:

• Real-time monitoring of chargepoint status
• User authentication (RFID card, app login, contactless payment)
• Usage and energy reports for billing tenants or fleet cost allocation
• Remote start/stop and firmware updates
• Alerts for faults, network disconnection

Popular UK CPMS operators: Pod Point, BP Pulse, Osprey, Mer, EO, Zaptec. Many chargepoint manufacturers also offer their own CPMS (Wallbox, Schneider, ABB).

Payment compliance: From late 2024, new public charge points must offer contactless payment (bank card, contactless device) — this is a requirement under the UK EV Infrastructure Regulations. RFID-only or app-only chargepoints are not compliant for public installations.

OZEV EV Infrastructure Grant

Current OZEV guidance (verify as schemes evolve):

• Available to businesses (any size), charities, and public sector
• £350 per socket, up to 40 sockets (per application), up to 75% of eligible costs
• Eligible costs include chargepoints, electrical infrastructure, cable trenching, surface reinstatement
• Requires an OZEV-authorised installer to claim the grant
• The customer does not receive the grant payment; the installer claims it and reduces the invoice accordingly
• One application per site address

To claim:

1. Customer confirms eligibility (business or public sector, UK address, off-street parking)
2. Installer registers as OZEV-authorised (via the OZEV portal)
3. Works completed; chargepoints from the OZEV approved list only
4. Installer submits claim via OZEV portal with photos, receipts, and installation certificates

Frequently Asked Questions

Does a commercial EV chargepoint need planning permission?

In England, installing EV chargepoints in a commercial car park is generally Permitted Development under Schedule 2, Part 2, Class D of the GPDO (Town and Country (General Permitted Development) (England) Order 2015) — no planning permission required for most cases. Exceptions: listed buildings; conservation areas (check with the local planning authority); installations that materially alter the appearance of a building. Scotland and Wales have their own PD rules — confirm locally.

Can a commercial property use a domestic chargepoint?

Technically, a domestic chargepoint installed at commercial premises will work, but it is not eligible for OZEV commercial grants and may not have the OCPP connectivity or robust weatherproofing required for a shared or public-facing location. Specify commercial-grade units (IP54+ weatherproofing, OCPP support, metal or reinforced enclosures) for commercial sites.

What is PAS 1899 and does it apply?

PAS 1899:2022 is the BSI standard for EV charging infrastructure. It covers: chargepoint accessibility, labelling, safety clearances, and payment requirements. It is referenced by government guidance for publicly accessible chargepoints and is effectively the UK operational standard for public charging. For a private workplace installation (staff-only access), full PAS 1899 compliance is not mandatory but is good practice.

How long does a 10-chargepoint installation take?

For a typical commercial car park with a sub-distribution board serving 10 × 7.4kW chargepoints: 3–5 days for cable installation and board work; 1 day for chargepoint fitting and commissioning. Total typically 1 week. DNO supply upgrades, if needed, can add months.

Regulations & Standards

• BS 7671:2018+A2:2022 — Chapter 722: EV chargepoint wiring; applies to commercial equally

• Electric Vehicles (Smart Charge Points) Regulations 2021 (SI 2021/1467) — all commercial chargepoints must be smart

• PAS 1899:2022 — publicly accessible EV chargepoints; accessibility, payment, and safety

• OCPP 1.6 / 2.0.1 — Open Charge Point Protocol; interoperability standard

• Building Regulations Approved Document S — Infrastructure for charging electric vehicles (commercial and residential)

• CDM Regulations 2015 — likely to apply for large commercial installations

• OZEV EV Infrastructure Grant — current commercial grant details

• PAS 1899:2022 — BSI — publicly accessible EV chargepoint standard

• IET Guidance Note 7 — EV Charging — commercial installation guidance

• ev charger installation types — chargepoint hardware types and specification

• three phase ev supply — three-phase supply for 22kW installations

• ct clamp load management — dynamic load management for multiple chargepoints

• bs 7671 ev wiring requirements — Chapter 722 compliance for commercial installs

• ev charging flats communal — multi-occupancy residential charging