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Cars and fuel options

This guide contains data on vehicles running on petrol and diesel, as well as ‘alternative’ fuels, such as Liquefied Petroleum Gas (LPG) and Compressed Natural Gas (CNG), and hybrid and electric vehicles.  Descriptions of the different fuel types and technologies are provided in the table below.

Table 1: Summary of fuels and technologies

Conventional Internal Combustion Engine (ICE) vehicles


‘Spark ignition’ fuelled by petrol a light fuel oil usually obtained from fossil fuel sources (crude oil).  Referred to as gasoline or ‘gas’ in North America.   Current forecourt blends contain up to 5% ethanol (E5).  Higher blends (E10, up to 10% ethanol) may be introduced.  All new cars are compatible with E10.  Forecourt labelling due to change to E5 (or higher blends) and filler cap label also expected to be introduced.


Internal combustion engine, compression ignition, fuelled by diesel, a heavy petroleum fraction usually obtained from fossil fuel sources (crude oil).  Current forecourt blends contain up to 7% of plant derived diesel (bio diesel).  Forecourt labelling due to change to B7 and a filler cap label is also expected to be introduced.


Compressed Natural Gas (CNG) or Liquefied Petroleum Gas (LPG)

Gas fuelled vehicles, either CNG (methane) or LPG (propane and/or butane). There is a small global market for such vehicles, usually dual fuel (gas/petrol) although few if any right hand drive LPG are available in the UK; one manufacturer has an arrangement for their models to be converted, a number of other companies offer after-market conversions.  LPG ‘autogas’ is available from around 1400 filling station forecourts.  CNG is available in about six stations.

Hybrid vehicles 

Hybrid Electric Vehicle (HEV)

A vehicle powered both by a conventional petrol or diesel engine and an electric battery. The battery is charged using excess energy from the engine, as well as by reclaiming the car’s kinetic energy when it brakes. These vehicles have a battery and an electric motor but cannot be connected and recharged by mains electricity and are not eligible for a government grant. Most hybrid electric vehicles exceed 75 g/km, the current definition of a ULEV, and are not eligible other incentives such as free access to the London Congestion Charing Zone.

Plug-in Hybrid EV (PHEV) 

PHEVs combine both a plug-in battery pack and electric motor with a conventional engine. Both the electric motor and the engine can drive the wheels. The battery is much smaller than in a battery electric vehicle, tending to only drive the wheels at low speeds or for limited range.  This is sufficient in most models to cover the average journey length of the UK driver. After the battery range is utilised, the hybrid capability means that the vehicle can continue journeys powered by its conventional engine.   Whilst these vehicles are no longer eligible for a grant there are environmental and cost benefits. 

Range Extended Battery EV (E-REVs) *  


E-REVs have a plug-in battery pack and electric motor, as well as a conventional engine. The electric motor always drives the wheels, with the engine acting as a generator to recharge the battery when it is depleted. Typically, these vehicles have a pure electric battery range of around 40 miles, before the vehicle switches to the range extender mode to continue the journey without range compromise.

Pure Electric Vehicles

Battery EV (BEV) *

BEVs are wholly driven by an electric motor, powered by a battery that can be plugged in to the mains. They rely entirely on electricity for fuel, which means they do not produce any tailpipe emissions.  At present, most of the BEVs on the market typically offer a range of around 100 miles, though some offer more. 

Hydrogen Fuel Cell Electric Vehicle (FCEV)* 

FCEVs share a large proportion of the electric motor and drive train technology with other electric and plug-in hybrid vehicles. However, their energy storage and conversion devices are different. Instead of taking electricity directly from the mains, these vehicles use a fuel cell to produce electricity to drive its electric motor. A fuel cell is an electrochemical device which generates electricity when continuously fed with hydrogen from an onboard tank that can quickly be refueled at around twenty stations.


*usually eligible for a plug-in car grant to help with the purchase cost of a new car. Please visit the Office for Low Emission Vehicles.  (OLEV) website for a list of current eligible vehicles: The Road to Zero Strategy considers the importance of the choice of fuel options in meeting the UKs carbon and air quality objectives and advice presented here is drawn from the strategy.

The Government remains committed to policies and incentives that are technology neutral. But it is essential that we understand the relative environmental performance of different technologies in the real world.
Battery electric vehicles are highly energy efficient and have zero tailpipe emissions. The assessment shows that they also have substantially lower greenhouse gas emissions than conventional vehicles, even when taking into account the electricity source and the electricity used for battery production. Assuming the current UK energy mix, battery electric vehicles produce the lowest greenhouse gas emissions of all the energy sources and fuels assessed, irrespective of vehicle type and operation.
Hydrogen fuel cell electric vehicles also have zero tailpipe emissions. Like battery electric vehicles, their ‘well-to-wheel’ (the overall assessment of climate change impact) greenhouse gas emissions depend on the method of energy production.
Although the environmental performance of range extended, plug-in, and non-plugin hybrids depends on their use and zero emission range, these vehicles are amongst the cleanest vehicles on the market and can bring significant environmental benefits. They are an important way of helping motorists make the switch to a different way of powering their vehicles.
Petrol cars and vans tend to have higher greenhouse gas emissions than their diesel equivalents but significantly lower emissions of NOx. Real world particulate emissions from petrol cars and vans are variable, with some petrol cars and vans (particularly those with direct injection engines) emitting higher levels of particulates than diesel equivalents.  We expect this to be addressed by the introduction of the Real Driving Emission (RDE) standards.
Real world emissions of NOx from diesel cars and vans that do not meet RDE standards (Euro 6d (temp) and Euro 6d) are typically much higher than from petrol equivalents. Cleaner diesel cars and vans can play an important part in reducing CO2 emissions from road transport during the transition to zero emission vehicles whilst meeting ever more stringent air quality standards. For diesel vehicles to play their part fully, their air quality impact must continue to be reduced. We want new cars and vans to be as clean as possible as fast as possible. We welcome the continued innovation and investment by vehicle manufacturers to develop cleaner diesel vehicles that meet the more challenging RDE requirements, delivering critical improvements in NOX emissions on the road.
Liquid petroleum gas (LPG) vehicles have similar well-to-wheel greenhouse gas emissions as diesel equivalents but generally have lower air pollutant emissions. Although a niche market, LPG vehicles may be a good current alternative to diesel in urban driving conditions. Natural gas vehicles also generally have lower air pollutant emissions than diesel equivalents but more efficient engines are required if they are to deliver significant greenhouse gas savings in heavy vehicles.
There are more than 150,000 ULEVs on UK roads and zero emission vehicles are an attractive option for many consumers today – offering the best environmental performance and in many cases cheaper running costs. If zero emission technologies are not currently practical options, the most appropriate vehicle technology will depend on individual circumstances, including location and usage pattern. For cars principally being used in urban areas where journeys tend to be shorter and at slower speeds, petrol hybrid, other alternatively fuelled or new conventional petrol cars are likely to be most suitable. Diesel is more suitable for cars that regularly drive long distances or carry heavy loads.
To help provide consumers with the information they need about the environmental performance of different vehicle and fuel options the Government will, in partnership with industry, consumer groups and motoring organisations, set up a Road Transport Emissions Advice Group to work together to ensure clear and consistent consumer messaging and advice.  The Energy Saving Trust (EST) has produced an animation to help navigate around all these technologies:
To find out more about electric vehicles, please visit  This highlights the range of ultralow emission cars on the market today and address myths about driving electric cars, notably cost and range.  With driving costs from 3p a mile and typical driving range exceeding 100 miles in a pure electric car on a single charge, pure electric vehicles, and range extended and plug in hybrid electric vehicles are an ever more attractive alternative to conventionally fuelled cars.  Costs and range are based upon the official NEDC economy and range figures which are obtained from official EU test data. These are intended for comparisons between vehicles and may not reflect real driving results.
EST has also produced a short film covering a range of issues around electric vehicles, running costs, maximising range and recharging:    
This covers most of the questions potential buyers may have including charging, range and the cost of fuel (electricity) for the vehicles. They offer a realistic and in-depth review of the viability of electric cars and vans, covering the choice, driving and living with an electric vehicle.

Link to Information on Car Fuel Data and CO2 emissions - next page