Our Ref: FOI-1880-2324
Thank you for your request received on 4 September 2023 asking for information about car emissions.
Your request has been considered in accordance with the requirements of the Environmental Information Regulations (EIR) and our information access policy. I can confirm that we do hold the information you require.
Transport for London is a provider of public transport and cycling infrastructure offer greener journeys. Our radio adverts communicate the improvements we’ve already made and are making across our network including:
• Our entire bus fleet being 100% low or zero-emission at the tailpipe
• Improving accessibility at our stations with over 200 step free access stations
• Improvements to the Circle, District, Hammersmith & City, and Metropolitan lines with a new signalling system for faster journeys in the future
These are examples of how “we’re making greener journeys brighter for everyone”. At the end of each radio advert, we state, ‘greener compared against average car emissions’ to explain the greener journeys.
We have used two data sources for the ‘greener compared against average car emissions’ statement which measure different types of emissions:
1. London Energy and Greenhouse Gas Inventory 2020
The data sources and method for the London Energy and Greenhouse Gas Inventory (LEGGI, 2020) can be found here (https://data.london.gov.uk/dataset/leggi). The road transport emissions reported for the LEGGI 2020 are derived from the 2019 road transport emissions reported in the LAEI 2019, using average traffic growth across London between 2019 and 2020, combined with changes in vehicle fleet composition to model emissions by vehicle type using the Emissions Factors Toolkit.
The LEGGI compares carbon (CO2) emissions across all modes of transport within the 32 London boroughs and the City of London. The total area covered by the LEGGI is approximately 1,579km2. The report illustrates that TfL transport produces, on average, less CO2 emissions than the car.
The LEGGI is produced by the Greater London Authority. The latest published data covers the period from 01/01/20 to 31/12/20 and reports the carbon emissions across all London boroughs. They publish this towards the end of the year. The GLA is aiming to publish the next update of the LEGGI, covering the year 2021, by the end of 2023. On average, TfL transport produces less carbon emissions than the car.
| Mode: | Car | Bus and coach | Rail Passenger | London Underground | DLR* | London Tram |
| Carbon (CO2) emissions (tonnes): | 2,581,776 | 651,717 | 317,975 | 182,350 | 10,554 | 2,533 |
Please note:
• Bus and coach include TfL buses
• Rail Passenger includes diesel and electric rail including TfL London Overground
• *DLR energy consumption has not been updated in the LEGGI for 2020 as more accurate estimates were not available. However, carbon emissions were updated, using the latest CO2 emission factors published by Government at the time of publication
2. London Atmospheric Emissions Inventory 2019
The London Atmospheric Emissions Inventory (LAEI, 2019) shows that although improvements to London’s air quality are being made, road transport is the single biggest contributor of nitrogen oxides (NOx) (which includes both nitrogen dioxide (NO2) and nitric oxide (NO)) and particulate matter (PM2.5) emissions in Greater London. The area covered by the LAEI includes the 32 London boroughs and the City of London, as well as areas outside Greater London up to the M25 motorway.
The LAEI 2019 data covers the period from 01/01/19 to 31/12/19. The methodology document published as part of the LAEI 2016 can be found here. A methodology document for the LAEI 2019 has not been published as it has not changed significantly; the same methodology was followed but the inventory was updated with the latest data.
The LAEI is a comprehensive inventory of all emissions across London including:
• Transport sources (road, rail, aviation and shipping)
• Industrial and Commercial sources (combustion of gas and other fuels, large
• Industrial sites, waste, construction, non-road mobile machinery);
• Domestic sources (combustion of gas and other fuels, biomass wood
• burning); and
• Other miscellaneous sources such as agriculture or accidental fire.
The LAEI is produced by the Greater London Authority and TfL with input from Imperial College London, Aether, Ricardo, Heathrow Airport and the Port of London Authority. The LAEI 2019 provides an update to the previous LAEI 2016.
The data reports the exhaust emissions (NOx and PM) in all London boroughs for cars, TfL buses and the remaining non-electrified parts of the national rail network in London. It also includes brake/tyre wear emissions for Particulate Matter (PM) for road vehicles.
2019 NOx emissions across all London boroughs
TfL rail and the London Underground are 100% electrified and do not emit NOx so there are no emissions to report for these modes. The Network Rail data shows the remaining non-electrified parts of the national rail network in London.
| Mode | Car | TfL bus | Network Rail |
| NOx emissions (tonnes) | 6,615 | 810 | 331 |
2019 PM emissions - exhaust and non-exhaust (which includes brake and tyre wear) across all London boroughsRoad transport PM emissions include exhaust and non-exhaust sources, but these are not included for London Underground and TfL rail due to a lack of data to quantify these. Despite this there is a significant difference in emissions for public transport vs. car modes.PM10 emissions across all London boroughs: | Mode | Car | TfL bus | Network rail |
| PM10 emissions (tonnes) | 1,116 | 120 | 18 |
2019 PM2.5 emissions across all London boroughs: | Mode | Car | TfL bus | Network rail |
| PM2.5 emissions (tonnes) | 576 | 55 | 13 |
If this is not the information you are looking for please do not hesitate to contact me.Please see the attached information sheet for details of your right to appeal.Yours sincerelyGemma JacobSenior FOI Case OfficerFOI Case Management TeamGeneral CounselTransport for London[email protected]