To use this methodology, select the vehicle size using the size drill option. Next, specify either the electricity consumed by setting the energyConsumption parameter or the distance travelled by setting the distance parameter. If a distance is specified, it is converted into a corresponding quantity of electricity by reference to a generic distance-based energy consumption factor (e.g. kWh per km) which is provided for each of the vehicle (i.e. drill) options. In either case, the quantity of electricity consumed is then converted into a quantity of CO2 emitted by multiplying by an emissions factor associated with the generation of grid electricity.
The returned value represents greenhouse gas emissions associated with electric car travel according to the energy or distance specified.
Setting the country
By default, the emissions factor for UK grid electricity generation is used to convert vehicle energy consumption into a quantity of greenhouse gas emissions. However, users can specify an alternative country by setting the country name or ISO code in the country parameter. In this case, CarbonKit will lookup the appropriate grid electricity emissions factor from the /home/energy/electricity dataset. If calculations are stored using profiles, the country can be specified within the profile metadata. Users should note, however, that directly specified country parameters override any set as profile metadata. This is useful, for example, for recording car journey's outside the user's own country.
Users can also set multiple occupancy for car travel, which 'shares' the vehicular emissions across all passengers. To specify the number of occupants set the occupants parameter. If no value is set, the calculation will be made on the basis of a single occupant (i.e. the driver).