EV Basics
BEV, PHEV, HEV and MHEV are four genuinely different things, and the marketing around them often blurs the lines. This guide explains exactly how each type works, what each one costs to run, where each one makes sense, and how to decide which fits your driving — with no agenda either way.
BEV (battery electric vehicle): runs only on electricity, plugs in to charge, no petrol involved. Tesla Model 3, Hyundai Ioniq 5, Kia EV6, BYD Atto 3, MG4, Renault Megane E-Tech. The 'EV' most people mean.
PHEV (plug-in hybrid electric vehicle): has both a petrol engine and a small battery (typically 10-20 kWh). Plugs in for 40-80 km of electric-only driving, then runs as a regular hybrid. BMW 330e, VW Tiguan eHybrid, MG HS PHEV.
HEV / self-charging hybrid: has a tiny battery (1-2 kWh) that charges itself from the petrol engine and braking. No plug. Adds efficiency to a petrol car but is fundamentally a petrol car. Toyota Corolla Hybrid, Honda Civic e:HEV.
MHEV / mild hybrid: 48V starter-generator that recovers a little braking energy and helps with stop-start. Marginal efficiency gain over a regular petrol car. Almost every modern European diesel and many petrols. Practically speaking, just a petrol car.
A BEV drives like an EV from the moment you switch on — silent, instant acceleration, no engine note, one-pedal driving via regenerative braking. The experience is consistent from 0 km to 500 km.
A PHEV drives like an EV for the first 40-80 km if you start with a full battery, then switches to behaving like a slightly heavy petrol hybrid for the rest of the journey. When the battery is empty, you have a petrol car carrying around an unused electric drivetrain. When it's full, you have an EV carrying around an unused petrol engine.
An HEV drives exactly like a petrol car with a slightly smoother stop-start. There's no electric-only mode beyond crawling distances. An MHEV drives like a petrol car. Period.
BEVs are by a wide margin the cheapest to run if you have home charging — typically £400-£600/year fuel for a 14,000 km driver in the UK on a mixed home/rapid mix. PHEVs are cheapest if you genuinely plug in every night and most journeys are within battery range; they get expensive fast if you don't plug in (you're hauling a 250 kg battery around for nothing).
HEVs and MHEVs are slightly cheaper than petrol equivalents per kilometre — typically 10-25% less fuel. No charging infrastructure required.
| Type | Example | Annual fuel |
|---|---|---|
| BEV (home off-peak) | Tesla Model 3 LR | £370 |
| BEV (rapid only) | Tesla Model 3 LR | £1,500 |
| PHEV (charged daily) | BMW 330e | £700 |
| PHEV (never plugged in) | BMW 330e | £1,950 |
| HEV (self-charging) | Toyota Corolla | £1,200 |
| Petrol equivalent | VW Golf 1.5 TSI | £1,320 |
BEV figures use 15 kWh/100 km. PHEV figures depend heavily on charging discipline.
BEV: anyone with home charging or a regular workplace charger, doing normal annual mileage. The right answer for most people. The longest motorway days are still convenient with modern rapid charging — see our first EV road trip guide.
PHEV: drivers who can plug in nightly but do regular long distances (over 200 km per day, several days a week), or drivers in regions with patchy rapid charging. Make sense as a compromise — only if the plug-in discipline actually happens.
HEV: drivers without any home charging access who do a lot of urban driving, or who simply aren't ready to deal with charging at all. A petrol car that uses less petrol.
MHEV: a petrol car with a sticker on it. Buy on petrol-car criteria; the MHEV badge is marketing.
PHEVs are the most controversial of the four. The marketing CO2 figures assume you charge them every night and drive mostly within battery range; large-fleet real-world data (especially from European company car schemes) shows many never get plugged in, in which case their actual fuel consumption is worse than a regular petrol equivalent because they're heavier.
Honest self-test: will you genuinely plug in every night, even when tired, even in winter, even when the battery's only at 30%? If yes, a PHEV is a sensible bridge technology. If you have any doubt, a BEV or an HEV is the more honest choice.
BEVs continue to enjoy the most favourable tax treatment in every country we cover — UK BiK 3% for 2026/27, Australian FBT exemption on novated leases, French and Italian regional incentives, ZTL access. PHEVs get diminishing benefit — UK BiK 8-12% depending on electric range, lower ZTL benefits, and some Italian regions now treating them like petrol cars.
HEVs and MHEVs get essentially the same tax treatment as petrol cars in all four countries, with rare regional exceptions. See our EV incentives guide for the full picture.
Stacking purchase, fuel, servicing, insurance and depreciation over five years and 70,000 km for a typical UK private buyer gives a single comparable number for each category. The BEV wins for any owner with home charging; the HEV wins for owners with no home charging access; the PHEV is a coin-flip that depends almost entirely on plug-in discipline.
| Category | BEV (Kia EV6) | PHEV charged (Tiguan eHybrid) | PHEV unplugged | HEV (Corolla) |
|---|---|---|---|---|
| Purchase price | £47,395 | £44,200 | £44,200 | £32,800 |
| 5-yr fuel/energy | £1,850 | £3,500 | £9,750 | £6,000 |
| 5-yr servicing | £900 | £1,800 | £1,800 | £1,650 |
| 5-yr insurance premium | £4,500 | £3,800 | £3,800 | £3,200 |
| 5-yr depreciation | £22,750 | £24,300 | £24,300 | £15,700 |
| Total 5-yr cost | £77,395 | £77,600 | £83,850 | £59,350 |
Assumes home off-peak charging for BEV/PHEV-charged. PHEV-unplugged assumes the car is treated as a petrol hybrid for 5 years.
The honest answer to 'which should I buy' depends on three questions. Do you have reliable home or workplace charging? How long is your typical day's driving? And how disciplined are you really going to be about plugging in?
Scenario A — suburban commuter, off-street parking, 40 km/day commute, occasional long trips. BEV is the clear answer. 95% of kWh comes from cheap home off-peak; rapid charging is the rare exception. Tesla Model 3, Kia EV6, Hyundai Ioniq 5, MG4 or BYD Atto 3 all fit. Scenario B — rural driver with home charging, 200 km/day mostly motorway, regular interstate runs. BEV still wins but you want a long-range one (Model 3 LR, EV6 GT-Line) and a good rapid network. Scenario C — flat-dweller with no home or workplace charging, low annual mileage. HEV is the most honest pick — cheaper to buy, no plug behaviour change, no infrastructure dependency.
Scenario D — high-mileage rep driver crossing remote regions with patchy rapid coverage. PHEV is a reasonable bridge if you'll genuinely plug in nightly. Scenario E — company car / salary-sacrifice driver in UK or Australia. BEV wins by a huge margin thanks to 3% BiK in the UK or FBT exemption in Australia, regardless of charging access.
Five-year residuals separate the smart EV buy from the painful one, and PHEVs sit in an awkward middle. BEV residuals from mainstream brands (Tesla, Kia, Hyundai, BMW) have stabilised at 45-55% over five years in 2026 — broadly equivalent to petrol equivalents in percentage terms. HEV residuals from Toyota and Honda remain industry-leading at 55-65%, helped by easy maintenance and broad buyer pool.
PHEV residuals have been the weakest of the four categories through 2024-26. The buyer pool is narrower, real-world fuel data has dented their green credentials, and several manufacturers have signalled phase-out plans. Expect 38-48% five-year residuals on most current PHEVs — a measurable hit on the TCO line. If you're picking a PHEV, lease rather than buy where possible; the depreciation risk sits with the leasing company, not you.
Headline manufacturer numbers are lab tests. Fleet-level real-world data tells a different and more reliable story. The Transport & Environment (T&E) 2025 PHEV report analysed over 100,000 European company-car PHEVs and found average real-world fuel consumption was 3-5× higher than WLTP figures — because most never got plugged in. The same study showed BEV consumption was within 10-15% of WLTP on average, a much smaller delta.
On the HEV side, Toyota's own multi-year telematics data on Corolla and RAV4 hybrids consistently shows real-world MPG within 5-8% of the official figure — the most honest fuel-economy claim in the industry. The takeaway: BEV and HEV manufacturer numbers are roughly trustworthy at fleet scale; PHEV numbers depend almost entirely on the individual owner's plug-in discipline and should be discounted heavily if you won't.
Often overlooked in the buying decision: each car type has very different infrastructure requirements at home and on the road. BEVs benefit hugely from a home wallbox (7-22 kW) and need access to public DC rapid for long trips. PHEVs only need a slow AC charger — a 3-pin granny cable works for their small batteries and most never need rapid charging at all. HEVs and MHEVs need no charging infrastructure of any kind.
This changes the up-front cost calculation. A BEV buyer with no off-street parking faces real friction; a PHEV buyer in the same situation can charge slowly from a regular socket overnight. An HEV buyer in a flat with no parking has the simplest life of all. For drivers without home charging access, the type hierarchy from most to least friction is: HEV → PHEV → BEV. For drivers with home charging, the order flips: BEV → PHEV → HEV.
Put this into practice
