New Car Fuel Consumption & Emission Figures

This page was last updated on 27th November 2023

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

Petrol ‘Spark ignition’ engine fuelled by petrol usually obtained from fossil fuel sources (crude oil).  Referred to as gasoline or ‘gas’ in North America.  During summer 2021, the standard (95 octane) petrol grade in Great Britain became E10. In Northern Ireland, this happened in early 2022. Almost all (95%) petrol-powered vehicles on the road today can use E10 petrol and all cars built since 2011 are compatible.
Diesel Compression ignition engine, 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).
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 1200 filling station forecourts.  CNG is available in about six stations.

Hybrid and Electric vehicles

Micro Hybrid A vehicle that stores some electricity for the start / stop function, but does not use stored energy in order to propel the vehicle
Mild Hybrid Electric Vehicle (MHEV) Uses a petrol or diesel engine to always power the vehicle, assisted by a small electric motor and battery in certain driving conditions.
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. Most hybrid electric vehicles exceed 75 g/km tailpipe CO2 emissions, the current definition of a ULEV, and are not eligible for incentives such as the cleaner vehicle discount allowing free access to the London Congestion Charging Zone.
Plug-in Hybrid Electric Vehicle (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 depending on the mode and requirements (for example all electric mode over many typical trips). The battery is much smaller than in a battery electric vehicle, tending to drive the vehicle for a 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.
Battery Electric Vehicle (BEV) BEVs are wholly driven by an electric motor, powered by a battery that is usually recharged from mains electricity either through a dedicated charge point or through the normal domestic supply at home, at business or the public charging network. They rely entirely on electricity for fuel, which means they do not produce any tailpipe emissions.  New BEVs typically offer ranges between 110 miles and 350 miles with ranges continuing to increase as new models and variants come to market.
Range Extended Electric Vehicle (REEV) / (E-REV) 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
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, with the only by-product being water, from an onboard tank that can quickly be refuelled at around twenty stations.

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. Battery electric vehicles 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.  As electricity generation is decarbonised the vehicles being driven by electricity are effectively de-carbonised as well.

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-plug-in 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.

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. Since September 2019 RDE step 1 (Euro 6d (Temp)) will be compulsory for almost all new registered cars on sale, with the more stringent RDE step 2 (Euro 6d) being a requirement from January 2021.  RDE has seen a significant reduction in real-world NOx emissions in diesel vehicles meeting those requirements and brings them much closer to petrol equivalents in terms of NOx emissions.

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 1 million 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.

Despite significant uptake in electric vehicles in the past 12 months, there remains a number of myths on topics such as range and supporting infrastructure. Earlier this year the Department for Transport published a guide that addresses those concerns. With driving costs from as little as 2p a mile and typical driving range exceeding 200 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 WLTP 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.

Energy Saving Trust has 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.