Glossary entry

Ultra Low Emission Vehicle (ULEV), Zero and Low Emission Vehicle (ZLEV) & Electric Vehicle (EV)

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Ultra Low Emissions Vehicle (ULEV)

Ultra Low Emissions Vehicle (ULEV) means a vehicle that emits less than [75g] of CO2 per km travelled as measured by the World-Harmonised Light-Vehicle Test Procedure (WLTP).

Electric Vehicle (EV)

Electric Vehicle (EV) means a vehicle that is capable of being propelled by electrical power derived from a storage battery.

Zero and Low Emission Vehicle (ZLEV)

Zero and Low Emission Vehicle (ZLEV) means a car or light commercial vehicle (LCV) which emits [0-50g] CO2/km as measured by the World-Harmonised LightVehicle Test Procedure (WLTP).

Light Commercial Vehicle (LCV)

Light Commercial Vehicle (LCV) means a vehicle used for the carriage of goods that has a maximum mass not exceeding 3.5 tonnes.

Drafting notes

The definition of ULEV is based on the definition in the Office for Low Emission Vehicles (OLEV) Road to Zero strategy.

The definition of electric vehicle is based on the definition of Charge Point in the Automated and Electric Vehicles Act 2018.

The definition of ZLEV is based on the definition in EU Regulation (EU) 2019/631 read in accordance with Commission Regulation (EU) 2017/1151.

The definition of an LCV is based on the European classification for fuel categories as used by the European Alternative Fuels Observatory (see References below).

Since 2018, vehicle emissions in the UK and across the EU for new car registrations have been measured using the WLTP. This was specified as the current European type-approval test in Commission Regulation (EU) 2017/1151 and was brought into the UK through The Road Vehicles (Defeat Devices, Fuel Economy and Type-Approval) (Amendment) Regulations 2018 (SI 2018/673). Prior to the introduction of WLTP, emissions testing was done using the New European Driving Cycle (NEDC) however this test is considered outdated and does not provide as accurate a measure of a vehicle’s real-world emissions. This clause therefore specifies that vehicles must be tested using the WLTP to qualify as ULEV/ZLEV.

The OLEV applies different CO2 standards to different types of vehicles (i.e. cars, vans, motorbikes, mopeds and taxis). Depending on the type of vehicle that is relevant to the contract, you may need to amend the level of CO2 in the definition to reflect the relevant standards.

It is expected that the definition of ULEV will change over time and become more restrictive. The OLEV has indicated that from 2021 it expects the definition of ULEVs to include only cars and vans which emit less than 50g/km CO2.

The terms ULEV and EV are sometimes used interchangeably, although ULEVs include ‘pure’ EVs (which have zero tail-pipe emissions) and hybrid models (which combine an electric motor with a combustion engine).

The term ZLEV is the term preferred by the European Commission in its publications.

Background information

Different types of ULEVs include:

  • Plug-in hybrid electric vehicles (PHEVs) which have a battery that is charged when connected to the electricity grid and switch between running on electricity and fossil fuels.
  • Hybrid electric vehicles (HEVs) which do not plug into the electricity grid, have a much smaller battery which is recharged while driving and switch between running on electricity and fossil fuels.
  • Battery electric vehicles (BEVs), or ‘all-electric’ vehicles, which use a battery as their only power source.
  • Fuel cell electric vehicles (FCEVs) which generate their own electricity onboard from a fuel such as hydrogen.


Procurement contracts, supply chain agreements to require that materials/goods are delivered in ULEVs/ ZLEVs.