The London Energy and Greenhouse Gas Inventory (LEGGI) is an emissions inventory which quantifies greenhouse gas (GHG) emissions released to the environment. It also quantifies emissions removed through Land Use, Land Change and Forestry sector activities.
It is produced on an annual basis to measure progress against the Mayor's CO2e reduction targets for London.
The inventory provides emissions in the following five categories:
I. Stationary Energy
II. Transport
III. Waste
IV. Industrial processes and product use (IPPU)
V. Agriculture, forestry, and other land use (AFOLU)
Publications earlier than the 2018 LEGGI only included emissions in the first two of these categories. However, LEGGI now provides estimates of these additional sectors for earlier years.
The coronavirus (COVID-19) pandemic and the resulting restrictions introduced in 2020 across London and the UK had major impacts on various aspects of society and the economy, which had a significant impact on greenhouse gas emissions. 2020 statistics should therefore be cited with caution, and the ongoing context of the pandemic should be considered when reviewing 2021 emissions.
In 2021, London’s CO2e emissions were 28.7 million tonnes. Over the short-term, emissions went down from 31.5 MtCO2e in 2019 (pre-pandemic), to 28.2 MtCO2e in 2020 and then in 2021 there was a small ‘pandemic rebound effect’ as emissions increased 1.7 per cent to 28.7 MtCO2e. Nationally there was a 5.0 per cent rebound in 2021.
Over the longer term, emissions are 37 per cent lower than 1990 levels and a 44 per cent below the peak of emissions in 2000. Despite a 29 per cent increase in population since 1990 and significant economic growth over that period, London’s per capita emissions have reduced by 51 per cent, from 6.7 tCO2e in 1990 to 3.3 tCO2e in 2021. Compared to the rest of the UK, London has the lowest per capita emissions of any region.