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Cars and Emissions

Climate change, often referred to as global warming, is the greatest environmental threat facing the world. When fossil fuels - petrol, diesel and most alternative fuels, are burnt for energy in an internal combustion engine the main by-products are water and carbon dioxide (CO2).  Although not directly harmful to human health, CO2 is the most significant of the greenhouse gases (GHG) contributing to climate change.  In the UK road transport is now the largest source of CO2 emissions.

The combustion process also results in gases and particles that can be hazardous to health: air pollution.  Particulate pollution is also produced from tyre, brake and road wear.  Poor roadside air quality causes immediate (acute effects) and/or longer term (chronic) impacts. 

The official tests that are used to type approve vehicles in terms of their fuel economy, CO2 and air pollutant emissions have been improved to provide data that is more representative.  From 1 January 2019 the Worldwide Harmonised Light Vehicle Test Procedure (WLTP) will be used for official consumer information on fuel economy.  A later date of 6 April 2020 for WLTP derived CO2 emissions has been set, to align with related changes to taxation and other motoring costs including incentives for some ultra low emission vehicles (ULEVs).  Official point of sale information will be amended from these dates.  Government continues to work with motor manufactures and other stakeholders to consider how information can be improved.

In July 2018 government set-out its strategy to meet both short and longer term reductions in CO2 and air quality emissions including ending the sale of conventional petrol and diesel vehicles by 2040.  Our ‘Road to Zero’ strategy sets out plans to enable a massive expansion of green infrastructure across the country, reducing emissions from the vehicles on the UK’s roads, and drive the uptake of zero emission cars and vans.