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Individual Scale Emissions

Non-Transport Emissions

Table 2. Non-Transport Sources of Emissions.

On an individual scale, most greenhouse gas emissions are likely to be from the use of fuel: electricity, heat and transport. Because much of this tends to come from common sources in the UK - the national grid, the rail network - the impact of an individual in these ways can be calculated relatively easily. Tables 2 and 3 [Ref. 8] give the rate (in CO2e) at which common sources emit greenhouse gases. The figure for waste is based on a percentage of the overall emissions for a typical landfill, so any landfill waste can be modelled in this way. Transport emissions are given per passenger per kilometre (p.km). Emissions from water usage are virtually negligible [Ref. 11] and so are not included.

Transport Emissions

Table 3. Transport Emissions.

More complicated to model are emissions from car and aeroplane travel. Car emissions vary according to make and model. Tables of emissions can be found online containing emissions of CO2 and NOx, usually given in grams per kilometre. NOx is a blanket term for a group of gases including Nitrous Oxide: emissions given in terms of NOx can be modelled as having a GWP of 270 [Ref. 9]. A database with emissions information for almost all common models of car can be found at www.vcacarfueldata .org.uk.

Aeroplane emissions can’t be modelled at a flat rate: different emissions rates are used for different lengths of journey. The emissions cost of air travel also varies according to class of seat: because business and first class flyers take up a greater proportion of floor space [Ref. 10], they are generally modelled as using a greater proportion of the fuel. Table 4 [Ref. 8] gives the various emissions costs (per passenger per kilometre) of air travel.

Table 4. Emission Costs of Air Travel.