EVs Explained by Type

ZERO EMISSION ELECTRIC VEHICLE (ZEV) DEFINED

A zero-emissions vehicle, or ZEV, is a vehicle that emits no exhaust gas from the onboard source of power. There are zero pollutants to human health and/or the environment emitted from the tail pipe of the vehicle.  Neither are there emitted any particulates (soot), hydrocarbons, carbon monoxide, ozone, lead, or various oxides of nitrogen. All of these are emitted by an Internal Combustion Engine (ICE) to varying degrees dependent upon date of manufacture and if the fuel is diesel or petrol. In the context of electric vehicles, ZEVs are powered exclusively by a battery pack and an electric motor and will be much cheaper to own and operate.

As per the rapidly increasing trend of electricity used to charge the batteries  being generated from renewable or clean sources such as wind, solar, hydroelectric or nuclear power then ZEVs will have ZERO “well-to-wheel” emissions.

PLUG IN HYBRID ELECTRIC VEHICLE (PHEV) DEFINED

An increasing number of Governments  have announced that manufacturers won’t be allowed to sell internal combustion engine (ICE) cars running purely on petrol or diesel from a point in the not too distant future. Whilst this will ultimately see lots more of us driving pure electric cars (ZEVs) plug-in hybrid electric vehicles (PHEVs) are also a major part of the plan.

A plug-in hybrid (PHEV) is a stepping stone between the ICE cars the vast majority of people drive today and a zero-emissions future. For most owners, the fact plug-in hybrid models can save them money will also help them find favour, and of course they're also designed to significantly reduce pollution.

How Does It Work?

Compared to Hybrids, Plug-in Hybrids (PHEVs) allow a greater distance to be driven on electricity alone. A plug-in hybrid has a larger battery pack, which requires charging from the mains electricity supply. Once fully charged, the journeys you can complete in pure EV mode are much longer, before the fuel-powered engine has to turn on to help power the car. A plug-in hybrid can operate using just electric power, just the conventional engines or a combination of both, providing extra power for times like overtaking or joining a motorway when extra acceleration is required.

Even though a hybrid’s ICE engine will produce emissions when it is running, the car’s overall emissions are low because the car will defer to electric-only mode whenever possible, at which times it produces no emissions at all. It generally does this at slow speeds, such as in city centres, stop-start traffic and car parks.

HYBRID ELECTRIC VEHICLE (HEV) DEFINED

A hybrid vehicle is fitted with one or more small electric motor that assists the conventional petrol or diesel engine, giving it a helping hand when accelerating. At low speeds and for short distances, most hybrid cars can also move using just electric power, saving more fuel.

Hybrid models are designed to excel in urban environments, where cars are typically driven slowly in lots of stop-start traffic. Here, it’s possible for the combustion engine in a hybrid to be inactive for long periods of time, saving fuel and avoiding polluting the air. Drive more quickly out of town or on the motorway though, and the conventional engine will need to run, reducing the hybrid benefits.

How Does It Work?

Most hybrid cars feature a petrol engine (although diesel hybrids are available) an electric motor and a small battery pack. As you drive along, some power from the engine and kinetic energy recuperated from slowing down and braking is used to charge the battery pack. Then, as you accelerate, electricity from the batteries powers the electric motor and helps the car gain speed, making the petrol engine’s job easier and improves fuel economy.

When enough charge is in the battery pack, most hybrid vehicles can also pull away just using electricity and travel for around half a mile at low speeds, using no fuel at all. This can be particularly handy in traffic jams, car parks and town centres where you don’t want to create air pollution.

EXTENDED RANGE ELECTRIC VEHICLE (EREV)

An Extended Range Electric Vehicle (EREV) - or Range Extended Electric Vehicle (REEV) - is a type of PHEV, but with the propulsion of the vehicle powered only by the electric motor. A small internal combustion engine is an on-board generator to top up the battery's charge - an EREV is a middle ground solution between a hybrid and an EV. In some (but not all) cases the EREV's battery can also be charged externally (plug in) with the car capable of being used as a conventional EV, but with the added safety net of the on-board generator extending the car's range. Hence the difficulty in defying the “Range” in electric miles.

EVs AND GOVERNMENT GRANTS

As of Autumn 2017, the Government is offering a grant to buyers of low-emission cars registered from new in the UK, provided their emissions fall below a set level intended to encourage drivers to choose less-polluting cars. The grants are available for buyers of pure electric vehicles (ZEVs), plug-in hybrid electric vehicles (PHEVS) and Hybrid Electric Vehicles (HEVs) and hydrogen fuel-cell cars.

The grant covers a maximum of 35% of the recommended retail cost of the car. Grants for plug-in cars fall into three categories:

Category 1

ZEVs and Plug-in hybrid cars that emit under 50g/km of CO2 and have an all-electric range of at least 70 miles are eligible for a grant to cover up to 35% of the purchase cost, up to a maximum of £4,500. Category 1 cars’ eligibility is unaffected by their recommended retail price.

Category 2

Plug-in hybrid cars that emit under 50g/km CO2 and have an all-electric range of 10-69 miles are eligible for a grant to cover up to 35% of the purchase cost, up to a maximum of £2,500. Category 2 cars must have a recommended retail price of no more than £60,000.

Category 3

Plug-in hybrid cars that emit 50-75g/km CO2 and have an all-electric range of at least 20 miles are eligible for a grant to cover up to 35% of the purchase cost, up to a maximum of £2,500.

No grant is available for second-hand vehicles.