Hybrid car types: MHEV, HEV, PHEV, REEV — differences and which to choose

The word «hybrid» on a trunk lid today can mean almost anything: from a small starter-generator that only helps the engine pull away, to a car that commutes to work every day on electricity alone and uses gasoline once a month. Fuel consumption, price, the need for a socket, and how the car will behave in five years all depend on the type of hybrid. Let’s break down the types of hybrid cars — MHEV, HEV (FHEV), PHEV and REEV (EREV) — how they differ, and which one to choose for your use case.

Contents

• Quickly: four types of hybrids
• MHEV — “mild” hybrid
• HEV and FHEV — full hybrid without a plug
• PHEV — hybrid that charges from a socket
• REEV (EREV) — electric car with a generator
• Hybrid comparison table
• Series, parallel and series-parallel layouts
• Which hybrid to choose
• Hybrid in Ukraine: charging, customs clearance, used market

Quickly: four types of hybrids

• MHEV (Mild Hybrid) — “mild” hybrid: a small electric motor assists the engine, but cannot drive the car on its own. No socket needed.
• HEV / FHEV (Full Hybrid) — full hybrid: can pull away and crawl in traffic on electricity only, and charges its battery by itself. No socket needed.
• PHEV (Plug-in Hybrid) — a hybrid with a large battery that is charged from the grid; it can drive dozens of kilometers on electricity.
• REEV / EREV (Range Extender) — the wheels are always driven by an electric motor, and the gasoline engine only generates electricity for the battery.

For comparison, there is also BEV — a “pure” electric car with no internal combustion engine. It is not a hybrid, but in the table below we placed it alongside so the difference is immediately visible.

MHEV — “mild” hybrid

Mild Hybrid Electric Vehicle is the simplest form of electrification. Instead of a conventional starter and alternator, it uses a starter-generator connected to the engine, plus a small 12- or 48-volt battery. The electric motor assists only when the engine is running: it helps the car pull away, smooths acceleration, provides a soft and quick restart for the start-stop system, and during braking returns part of the energy to the battery.

The key thing to know about MHEV: such a car cannot drive on electricity alone (some 48-volt systems can coast briefly with the engine off, but that is the exception). So an “MHEV hybrid” is essentially a normal gasoline or diesel car with an assistant. Savings are moderate and most noticeable in the city, where there are many stops. Examples include the Nissan Qashqai with a 12-volt Mild Hybrid system, and Volvo with B4 and B5 engines (48 V).

HEV and FHEV — full hybrid without a plug

HEV (Hybrid Electric Vehicle) and FHEV (Full Hybrid Electric Vehicle) are the same thing: a full hybrid. The FHEV badge is used, for example, by Ford (Kuga FHEV), while other brands simply write Hybrid or HEV. A common mistake is to think FHEV is a plug-in hybrid: it is not — charging from the grid exists only in PHEV.

A full hybrid has a more powerful electric motor and a traction battery with a small capacity (usually around 1–2 kWh). That is enough to pull away, crawl in traffic, and maneuver in a parking lot with the engine off. The car charges the battery itself — via the engine and regenerative braking. Therefore you do not need to charge an HEV, and you cannot: it simply has no socket for a cable.

Classic examples are Toyota with the Toyota Hybrid System, such as the new Toyota Camry XV80, RAV4 Hybrid and Corolla Cross, as well as Honda CR-V e:HEV and Ford Kuga FHEV. A special case is Nissan e-POWER: it is also a full hybrid without a plug, but a series one — more on that below.

PHEV — hybrid that charges from a socket

Plug-in Hybrid Electric Vehicle is a full hybrid with a large battery and a charging port. Battery capacity here is several times larger than in an HEV: for example, the updated Mitsubishi Outlander PHEV has 22.7 kWh and up to 86 km on electricity under the WLTP cycle. Such a car can commute to work and back every day like an electric car, and on a long trip — like a regular hybrid.

A nuance that advertising brochures keep quiet about: a PHEV is cost-effective only when it is charged regularly. The impressive low official fuel consumption is calculated with the distance driven on a charged battery included. A European Commission report based on on-board fuel counter data showed that real CO₂ emissions (and thus fuel consumption) in PHEVs are on average 3.5 times higher than laboratory figures — precisely because owners charge them less often than the test assumes. Without a socket, a PHEV carries a heavy battery for nothing and consumes no less than a regular hybrid.

Examples for 2025–2026: Mitsubishi Outlander PHEV, Toyota RAV4 Plug-in, Skoda Superb iV, and even a pickup — Ford Ranger Plug-in Hybrid.

REEV (EREV) — electric car with a generator

REEV (Range-Extended Electric Vehicle), or EREV, is essentially an electric car that has a gasoline “range extender.” The wheels are driven only by the electric motor, while the internal combustion engine is not mechanically connected to the wheels: it works as a generator and recharges the battery. The battery can also be charged from a socket, as in a PHEV.

A vivid example is the Mazda MX-30 e-Skyactiv R-EV: a 17.8 kWh battery, up to 85 km on electricity under WLTP, and a compact rotary engine acting as the generator. The REEV concept is used at scale by Chinese manufacturers — for example, the XPENG L03 in the EREV version. The driver gets the behavior of an electric car — quiet running and instant acceleration — but without being tied to charging stations on long trips.

Hybrid comparison table

Series, parallel and series-parallel layouts

The abbreviations MHEV, HEV or PHEV describe how electrified a car is. The layout, on the other hand, shows exactly how the engine and electric motor transmit force to the wheels.

Parallel layout

The engine and the electric motor can drive the wheels together or alternately through a shared transmission. This is how all MHEVs are built, as well as some full hybrids and PHEVs with an electric motor integrated into the gearbox. The advantage is efficiency on the highway, when the engine drives the wheels directly.

Series layout

The engine is not connected to the wheels: it only spins a generator, while the electric motor provides propulsion. This is REEV and Nissan e-POWER (in particular on Qashqai and X-Trail, and also in the new Nissan Rogue e-POWER). The car drives like an electric car, but at high speed the losses from double energy conversion are more noticeable.

Series-parallel layout

The system chooses the mode itself: in the city it works mostly like a series hybrid, on the highway it allows the engine to drive the wheels directly. This is how the Toyota Hybrid System works with a planetary power-split device, and Honda e:HEV, which at high speed engages a direct drive from the engine. This layout is what gives full hybrids the best balance between city and highway.

Which hybrid to choose

• Mainly city driving, nowhere to charge — a full hybrid HEV: the biggest savings are in traffic jams, with no dependence on a socket.
• A socket at home or work, daily mileage within the electric range — PHEV or REEV: most trips will be on electricity, and gasoline is for longer routes.
• Lots of highway, little city — MHEV or diesel: at steady speed the advantage of a full hybrid is small, and an MHEV is cheaper.
• You want the behavior of an electric car but fear being far from chargers — REEV or a series-layout hybrid like e-POWER.
• Limited budget — MHEV: the surcharge for electrification is minimal, and the design is closest to a conventional car.

If you are choosing between specific models, take a look at our comparison of Toyota RAV4 2026 and Honda CR-V 2026 — two of the most popular full hybrids in the crossover class.

Hybrid in Ukraine: charging, customs clearance, used market

Charging and power outages

HEVs and MHEVs do not depend on the grid at all — for Ukraine, with its outages, that is a strong argument. During outages, PHEVs and REEVs simply run on gasoline, so they remain mobile. A PHEV is most convenient to charge at home or at work: from a regular socket, the battery usually fills overnight. Before buying a PHEV in an apartment building, honestly assess where you will charge it every day.

Customs clearance

There is no separate “hybrid” benefit in the Tax Code for MHEVs, HEVs and PHEVs whose engine can drive the wheels: excise is calculated using the same formula as for a gasoline car (base rate × engine displacement in liters × age coefficient), plus duty and VAT. The word Hybrid in the documents by itself does not change the rate — the decisive factor is the commodity code under УКТ ЗЕД. For electric cars, excise is 1 euro per 1 kWh of battery capacity, and the VAT exemption for their import does not apply from January 1, 2026. It is better to do an exact calculation for a specific car with a customs broker.

Used market and operation

When buying a used hybrid, check not only the engine but also the condition of the traction battery (capacity diagnostics at a service station or at a dealer), the operation of the battery cooling system, and the service history. In a PHEV, additionally check the charging port and cable, as well as the onboard charger. One more detail that is often noticed only after purchase: in many hybrids the battery sits under the trunk floor or under the rear seats, so the floor is raised and standard mats do not fit. For such versions, separate EVA mats and rubber trunk mats are available marked “hybrid.”

We deliver with Nova Poshta across Ukraine; orders from 15,000 ₴ — free with our own transport.