5.3.2. Economy-wide environmental impacts Given the existence of fuel emission coefficients and knowledge of the fuel-use of industries, it is possible to construct integrated IO and SAM accounting systems that include energy demands and emissions. These integrated databases can be used to calibrate energy–economy–environment IO, SAM and CGE models, which can be used to track the impact of disturbances on GHGs for example. The resultant databases can be used to compute carbon footprints in a rigorous and transparent way that reflects system-wide impacts on emissions (including those that arise indirectly through intermediate purchases and those that are induced by consumers' expenditure responding to changes in income). In the context of DG, this would allow an assessment of its impact on a particular region's carbon footprint. However, in the context of ‘open’ regions or localities (where trade flows are relatively large), it would be important to distinguish between production-oriented measures of emissions (as emphasised by Kyoto) and consumption-oriented measures. In two (or more) region context it would be possible to identify the CO2 ‘trade balance’ between regions, and the impact of DG on this.29 Clearly, small, open regions may initially import electricity from beyond its geographic boundaries, whereas CHP development may bring generation within those boundaries but result in a cut in imports (and possible electricity generation) elsewhere. Productionoriented measures would clearly indicate an increase in emissions, whereas consumption-oriented measures may indicate the reverse.