The category /transport/bus contains data on greenhouse gas emissions associated with bus travel. All subcategories are based on generic emissions factors, describing greenhouse gas emissions in terms of journey distances for distinct representative types of bus travel.

The following subcategories are available in the /transport/bus category.

Generic bus transport

The category /transport/bus/generic contains passenger-based emissions data relating to bus travel in the UK and the Republic of Ireland, with sources including the UK government agency DEFRA. This category measures CO2 emissions only, and should be considered to represent a useful first point of entry to bus-related emissions. This category is used by the UK Government Act On CO2 website.

Generic bus transport - DEFRA

The DEFRA Generic bus transport category contains the most recently published DEFRA data on greenhouse gas emissions associated with representative passenger bus types in UK. The methodology uses distance-based, per passenger emissions factors, requiring the user to specify the distance travelled. This category includes CO2, CH4 and N2O emissions as part of each calculation.

Generic bus transport - GHG Protocol

The category /transport/bus/generic/ghgp contains data on bus-associated emissions sourced from the latest World Resources Institute Greenhouse Gas Protocol (GHGP) documentation. This category includes emissions methodologies for bus travel in several geographic contexts, and includes both per vehicle and per passenger emissions factors. This category also features separate functionality for calculating biofuel emissions.

Generic bus transport - IPCC

The category /transport/bus/generic/ipcc contains data on bus-associated emissions sourced from the IPCC Guidelines for National Greenhouse Gas Inventories. This category contains data and methodologies for bus travel in European and US contexts and calculates emissions on per vehicle basis, using fuel consumption or a combination of fuel consumption, fuel efficiency and distance.

Bus travel with occupancy

The category /transport/bus/generic/occupancy also contains older GHGP data for several types of bus transport. The category is based around per vehicle emissions factors but includes a facility for specifying both total vehicle occupancy and the number of passengers accountable, in order to accurately determine the share of vehicular emissions attributable to passengers under the user's consideration.