Consumption-based GHG emissions of C40 cities

01 Mar 2018

This report presents the methodology and results of a study investigating the consumption-based greenhouse gas emissions (GHG) from 79 cities. 
To support evidence-based climate action planning, many cities have developed sector-based GHG inventories using standards such as the Global Protocol for Community-Scale Greenhouse Gas Emission Inventories (GPC).
These focus primarily on GHG emissions from energy use within the city boundary, through direct combustion or the consumption of grid-supplied electricity, heating and/or cooling, as well as GHG emissions from the treatment of waste. The vitality of cities, however, also gives rise to the production of signi cant quantities of GHG emissions outside their boundaries. To estimate this impact, C40 conducted an assessment of the consump- tion-based GHG emissions for 79 of its member cities.
The consumption-based approach captures direct and lifecycle GHG emissions of goods and services (inlcuding those from raw materials, manufacture, distribution, retail and disposal) and allocates GHG emissions to the final consumers of those goods and services, rather than to the original producers of those GHG emissions. GHG emissions from visitor activities and the production of goods and services within the city boundary that are exported for consumption outside the city boundary are excluded.