EV charging infrastructure explained: chargepoint types, architecture and UK rules

EV charging infrastructure is everything between the electricity network and the car's battery: the supply and meter, the protected circuit, the chargepoint, the cable and connector, and the software that controls and bills each session. In the UK it ranges from a 2.3 kW three-pin plug at home to 350 kW ultra-rapid hubs, and it is governed by a short list of rules: BS 7671 for the wiring, the Smart Charge Points Regulations for private chargers, Part S for new buildings and the Public Charge Point Regulations 2023 for public networks.

This guide is for fleet and facilities managers who are new to EVs and need to talk confidently to installers and charge point operators. It defines the vocabulary, walks through the architecture brick by brick, sets out power levels and connectors, the UK regulations and who may install what, gives the latest network figures and explains where a fleet really needs hardware. Voltaback sits on the data layer: it reads charging sessions from the car rather than from the charger, so no infrastructure is needed to measure and reimburse home charging.

The vocabulary, in one table

Chargepoint or infrastructure: what is the difference?

A chargepoint is one box. Charging infrastructure is the whole system around it: the grid connection, the electrical installation, the chargers, the communications and the software. Two identical chargepoints can perform very differently depending on the supply behind them and the back office that controls them. When an installer quotes "a charger", ask what part of the infrastructure is included.

The architecture, brick by brick

From the network to the battery, a charging installation has six layers.

1. The supply and the meter

Electricity arrives from the DNO's network through the building's service cable, cut-out and electricity meter. The capacity of that supply sets the ceiling for all charging on site. A typical UK home has a single-phase supply, often fused at 60 to 100 A. Commercial sites usually have three-phase supplies with far more headroom, but also far more existing load.

2. The distribution board and the dedicated circuit

Each chargepoint is fed by its own dedicated circuit from a distribution board, sized for continuous load: an EV draws its full current for hours, unlike a kettle. Long cable runs need larger cables to limit voltage drop.

3. The protections

BS 7671 sets out specific protection for EV charging circuits:

• Residual current protection: an RCD of at least Type A, combined with protection against DC fault currents (built into many chargers), or a Type B RCD.
• Overcurrent protection for the circuit.
• Protection against an open PEN conductor where the supply uses PME earthing and the charger is outdoors, either through a device in the charger or a separate earthing arrangement.
• Surge protection where the risk assessment requires it.

These are the points where an amateur installation fails, and why charging circuits must be designed and certified by a competent electrician.

4. The chargepoint

The chargepoint controls the charge: it communicates with the car, checks that the cable is connected and safe, and only then switches on the power. For AC charging, the chargepoint supplies alternating current and the car's onboard charger converts it to DC for the battery, so the car's onboard charger limits the speed (often 7 or 11 kW). For DC charging, the conversion happens in the chargepoint itself, which is why DC chargers are larger, more expensive and much faster.

5. The cable and the connector

Either tethered (the cable is attached to the charger) or untethered (a socket, and the driver brings the cable). Public rapid chargers are always tethered; home and workplace AC chargers can be either.

6. The software layer

Smart chargers connect to a back office over Wi-Fi, Ethernet or mobile data, usually speaking OCPP. The back office identifies users, starts and stops sessions, applies tariffs, reports faults, manages load and, at home, shifts charging to off-peak hours. Choosing chargers that support an open protocol such as OCPP means you can change back office provider without replacing the hardware.

Metering sits in this layer too. For billing, the charger's meter should be MID-certified. For reimbursing home charging, the source of the kWh matters just as much: Voltaback relies on the home's MID-certified meter, not on a standalone cable meter, and identifies each session from the car's own data.

The four charging modes

The international standard IEC 61851 defines four charging modes, which explain the safety level of each solution:

Power levels: from 2.3 kW to 350 kW

Categories follow Zapmap's connector guide and the official statistics bands. Miles per hour are our order of magnitude; the real figure depends on the car, the temperature and the battery's state of charge, as DC charging slows sharply above about 80 %. Our guide on how long it takes to charge an electric car gives times by car and charger.

Almost all UK homes are single-phase, so home charging tops out at about 7.4 kW. That is enough: a car plugged in overnight for 10 hours at 7 kW receives about 70 kWh, more than most daily driving requires.

Connectors: Type 2, CCS and the rest

Source: Zapmap, connector types. For a fleet buying today, Type 2 for AC and CCS for DC cover essentially every new car.

The UK rules that shape charging infrastructure

BS 7671 and the IET Code of Practice

BS 7671, the IET Wiring Regulations, applies to every electrical installation, with a dedicated section on EV charging. Amendment 4:2026 was published on 15 April 2026, and the previous version was withdrawn on 15 October 2026. The IET Code of Practice for Electric Vehicle Charging Equipment Installation (5th edition, 2023) adds practical guidance on design, earthing, protection and DNO notification.

The Electric Vehicles (Smart Charge Points) Regulations 2021

Since 30 June 2022, chargepoints sold for private use in Great Britain, at homes and workplaces, must be smart: able to connect to a communications network, to respond to signals and shift charging, with default charging outside peak hours, a randomised delay, security requirements and the ability to measure and display electricity use. Public and rapid chargers are excluded. Sources: GOV.UK, smart charge points regulations, legislation.gov.uk.

Building Regulations Part S

In England, Approved Document S requires charge points and cable routes in new residential and non-residential buildings with parking, and in major renovations, since 15 June 2022 (GOV.UK, Approved Document S). It does not require existing car parks to be retrofitted. Our article on EV charging building regulations explains what it requires for company car parks.

The Public Charge Point Regulations 2023

In force since 24 November 2023, these regulations apply to chargepoints accessible to the public, including free ones, but not to workplaces closed to the public, residential premises or manufacturer-only networks. They require charge point operators to provide:

• contactless payment on new public chargers of 8 kW and above and on existing ones of 50 kW and above;
• payment roaming through at least one third-party provider;
• 99 % reliability on average across each operator's rapid network over the calendar year, published on the operator's website;
• a free, staffed 24/7 helpline, advertised at every chargepoint;
• open data through OCPI;
• pricing displayed in pence per kWh, with the maximum price shown before charging;
• regular reporting to the Office for Product Safety and Standards (OPSS), which enforces the rules, with civil penalties of up to £10,000 per breach.

Sources: legislation.gov.uk, SI 2023/1168, GOV.UK, Public Charge Point Regulations 2023 guidance, GOV.UK, regulations for public charge points.

For a fleet, these rules matter in two ways: drivers using public chargers can expect contactless and clear pricing, and a company that opens its own chargers to the public becomes a charge point operator with these obligations.

Who can install charging infrastructure?

• Any chargepoint, home or workplace: a qualified electrician, normally registered with a competent person scheme (NICEIC, NAPIT or equivalent), so that the work can be self-certified under Building Regulations. EV-specific training is expected.
• To claim a government grant: the installer must be OZEV-authorised (Office for Zero Emission Vehicles). Without one, no grant can be claimed.
• The DNO: for small installations, the installer follows the Energy Networks Association process to notify the DNO before or after installation; larger workplace or depot projects need a connection application. The DNO quotes within 5 to 65 working days, and you have 90 days to accept (GOV.UK).
• A 3-pin socket used with a granny charger: no chargepoint installation, but the socket and circuit should be checked by an electrician before regular use.

The installer issues an Electrical Installation Certificate and the commissioning documents. Keep them: insurers, landlords and grant schemes ask for them.

The UK public network in figures

On 1 July 2026, the UK had 121,171 public EV chargers, or 174.9 per 100,000 people, of which 28,887 were rapid or faster (50 kW and above). By speed: 49 % standard (3 to 8 kW), 27 % standard plus (8 to 50 kW), 12 % rapid (50 to 150 kW) and 12 % ultra-rapid (150 kW and above). Source: GOV.UK, public EV charging infrastructure statistics, 1 July 2026, published 27 August 2026. From 2026, the official series counts chargers rather than devices, so older "device" figures are not directly comparable.

The price of that network varies widely: about 54p per kWh on average on public AC chargers and 79p on rapid and ultra-rapid chargers in September 2026, against 26.32p at home on the October to December 2026 price cap (Zapmap Price Index, Ofgem).

Home, workplace or public: what changes

Grants and tax in 2026

• Workplace Charging Scheme: up to £500 per socket, up to 75 % of costs, 40 sockets maximum, OZEV-authorised installer, applications until 31 March 2027 (Find a Grant). Our article on the Workplace Charging Scheme explains the application.
• 100 % first-year allowance on new chargepoint equipment, until 31 March 2027 for Corporation Tax (GOV.UK).
• Household grants: the EV chargepoint grant supports flat owners and people renting a property with dedicated parking (GOV.UK).
• A home charger for a company car provided by the employer is not a taxable benefit (HMRC EIM23900).

What infrastructure costs, at the right size

Sources: Electric Car Scheme, Blink Charging UK. The right size is the one that matches dwell time: a car parked for eight hours does not need a 22 kW socket, and a van with a one-hour turnaround cannot live on 7 kW. Our guide to workplace EV charger installation gives a sizing method for 50 vehicles, and the charging installation recommendation simulator sorts your vehicles into profiles.

Fleets: you do not need a connected charger to reimburse home charging

Many fleet managers assume that to pay drivers back for home charging, every home needs a smart charger connected to the company's back office. It does not.

The UK rule is simple: an employer can reimburse the electricity used to charge a company car at home free of tax and National Insurance, private miles included, as long as the payment relates solely to the company car (HMRC EIM23900). What that requires is reliable kWh per session tied to the car, and the driver's tariff. That data exists in the car itself.

Voltaback reads each charging session from the car's own data, across more than 48 brands, whatever the charger: a smart wallbox of any make, an old non-smart charger, or a 3-pin plug. It values each kWh at the driver's real tariff (or at HMRC's 7p per mile Advisory Electricity Rate if you prefer), and produces a monthly export ready to import into your payroll software. Nothing is installed, and the company never receives drivers' locations. The measurement is audited by an independent third party (1.22 % average relative error).

Where hardware is genuinely needed, at a depot or for drivers without home charging, Voltaback does not install it, but our installer quotes service helps you get comparable quotes.

Next step: build only the infrastructure you need

Charging infrastructure is a chain, and the cheapest link for a company car is the driver's own home. Equip depots and drivers without home charging, and measure the rest from the car. Talk to our team to see how Voltaback reimburses home charging at its real cost, with no hardware, across your whole fleet.