Glossary entry

Green Transport

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Option 1

Green Transport means any mode of transport, conventionally motorised or powered by an [Alternative Power Source][Alternative Fuel], which is classed by the UK Vehicle Certification Agency as an Ultra-Low Emissions Vehicle or a Zero Emissions Vehicle.

Option 2

Green Transport means any mode of transport which is powered by [an Alternative Power Source][Alternative Fuel] or physical human force such that, when in operation, it produces [minimal][almost no] Greenhouse Gases.

Related terms

Alternative Fuel

Alternative Fuel means fuel or power sources which serve, at least partly, as a substitute for fossil oil sources in the energy supply to transport and which have the potential to contribute to its decarbonisation and enhance the Environmental Performance of the transport sector and includes:

(i) electricity;
(ii) hydrogen;
(iii) liquid or gaseous biofuels derived from biomass2;
(iv) synthetic and paraffinic fuels;
(v) natural gas, including biomethane in gaseous form (compressed natural gas) and liquefied form (liquefied natural gas (LNG)); and
(vi) liquefied petroleum gas.

Alternative Power Source

Alternative Power Source means all alternative sources of energy for transport, such as electricity and hydrogen, that do not have to be released through combustion or non-combustion oxidation.

Ultra-Low Emissions Vehicle (ULEV)

As defined in this Glossary.

Zero Emissions Vehicle

Zero Emissions Vehicle means an engine, motor, process or other energy source that, while in operation, produces no Greenhouse Gases.

Drafting notes

Option 1 is inclusive of modes of transport that are powered by fossil fuels but produce low emissions. This version may be useful at present as we transition towards green transport.

Option 2 defines Green Transport exclusively as modes of zero-emission transport which utilise renewable energy sources or are powered by human forces (e.g. walking, cycling).

Note the definition of Zero Emissions Vehicle above differs from the definition of Zero and Low Emission Vehicle (ZLEV) given as a related term in the ULEV definition, as that definition is based on the definition in EU Regulation (EU) 2019/631 which sets CO2 emissions performance targets for new passenger cars and new light commercial vehicles.

As time goes on, the Option 1 definition might be replaced by the Option 2 definition e.g. when the sale of new conventional petrol and diesel cars and vans ends in 2040 as set out in the Government’s UK plan for tackling roadside nitrogen dioxide concentrations Detailed plan (July 2017) (see References below).

The definition of ‘Alternative Power Source’ mirrors the definition of ‘Power Source’ at paragraph 5 of Directive 2014/94/EU of the European Parliament and of the Council of 22 October 2014 on the deployment of alternative fuels infrastructure (see References below).

Green Transport types include, but are not limited to:

  • Walking.
  • Bicycles.
  • Motorcycles (electric or biodiesel).
  • Cars (electric or biodiesel).
  • Buses (electric, hydrogen or biodiesel).
  • Taxis (electric or biodiesel).
  • Trains (heavy rail).
  • Underground railway systems.
  • Light rail systems (e.g. trams, Docklands Light Railway).
  • Aircraft (solar or biodiesel powered).


National climate laws, private transport franchising obligations, corporate social responsibility (CSR) documents, public sector fleet procurement agreements (including in the public sector).