How to Compare EV Fast Charging for UK Trips

For a car charged mostly at home or work, the fastest DC figure may rarely matter. For frequent motorway journeys, compare the time and energy added at stops you will use, not the largest brochure kW. This UK guide is a method, not a model ranking: trims differ, and no matched vehicle test was performed. Start with your daily miles, home charging access, longest regular trip, winter use and networks along the route. For what voltage means, see the 800V and 400V guide.

For daily use, check what AC charging your home, workplace or local destination can provide. If it covers routine energy, a slower DC maximum may have little effect. Without off-street charging, find dependable public options near home. For road trips, map the corridor: rapid sites, backups, amenities, connector, payment, live status and distance between stops. DfT’s UK total includes many on-street and destination chargers; a large national count does not prove a convenient high-power stop exists on your route. Recheck maps before travel.

A fair comparison uses the exact UK version of each car, then matches the SOC window (for example, 10-80%), battery temperature or preconditioning, and charger type. Use a compatible site with enough power for both. Label each time as maker-published, independently tested or personally observed. Do not compare different SOC windows or a warm-battery test with a cold arrival. IONITY says curves vary by car and temperature and SOC affect speed; Tesla UK lists similar conditions. These factors justify controlled comparisons, not a universal adjustment or a diagnosis of a fault.

Peak power is the highest moment. Average power over a session is energy added divided by connection time, so it captures tapering better. Match measurement boundaries: battery energy stored (kWh) ÷ average battery-side charging power (kW) × 60 = minutes. If a hypothetical car stores 42 kWh from 10% to 70% at an average 100 kW battery-side, energy transfer takes about 25 minutes. Do not divide battery SOC gain by a charger-display average unless both refer to the same side. Plug-in, authentication, queues and payment add time. Compare the same SOC window and inspect the curve; IONITY says peak may last only part of a session and power generally falls as SOC rises.

Here is an original calculation to show how to think about a stop. Assume, purely for illustration, a vehicle with 60 kWh usable capacity, arriving at 20% and leaving at 70%. The battery gains 30 kWh (60 × 0.50). If one hypothetical car averages 90 kW of battery-side net power over that window, energy transfer is 30 ÷ 90 × 60 = 20 minutes. If another averages 150 kW of battery-side net power, it is 30 ÷ 150 × 60 = 12 minutes. That eight-minute difference follows only from the assumed averages; it is not a claim about any model, charger, measured result or total stop time. Real charge curves, usable capacity, temperature, losses and site limits change the answer.

Energy cost is separate from energy stored. For this independent illustration, assume the charger meter bills 33 kWh for the session; that billed quantity is a separate input from the 30 kWh stored in the battery, and is not a claimed loss ratio. At assumed tariffs of 30p/kWh and 75p/kWh, the energy charge would be £9.90 and £24.75 respectively, before any separate fees. These sample inputs are not current UK tariffs or a forecast. IONITY says its applicable price depends on tariff, subscription, country and location, so check the price shown in the payment method for the actual site. Use CathayEV’s running-cost calculator for your own home/public mix and range estimator for route planning inputs; both are estimates, not a substitute for a charger-specific plan.

Before choosing, ask:

1. Is this the exact UK trim and model year, and what connector does it use? 2. What are its maximum AC and DC rates?

3. What is the maker’s time over a named SOC window, and can you see the curve? 4. Can navigation precondition the battery for a rapid stop?

5. Which networks accept your payment method? 6. Which route sites have suitable power, backups and live availability?

7. What tariff will you pay? 8. For a real session, record arrival SOC, temperature, preconditioning if known, charger rating, average/peak power, energy added, elapsed time and payment. One session is evidence for those conditions, not a universal guarantee.