This is how we think it works. New electricity interconnections reduce emissions by enabling transfers of non-emitting electricity into a jurisdiction that would otherwise produce its electricity from fossil fuels, coal being the key example.
Electricity interconnections will allow for a greater utilization rate for existing hydro resources. Some hydro-rich provinces currently have a surplus of that hydroelectricity, so new transmission will allow for this surplus to be used by neighbouring jurisdictions that currently rely on fossil resources. Enhancing that two-way flow of electricity between regions may also help balance generation associated with variable renewable power, as I said before, by enhancing the geographic scope of the supply mix.
If we look at GHG emission reductions from transmission interconnection projects, it really depends on the size of the projects, the amount of power transmitted, whether the power is non-emitting, and what type of fossil fuel plant they're replacing. Just to give you a concrete example, for a 500-megawatt line that's used to move non-emitting electricity from B.C. to Alberta, for instance, you would expect to get between one and two megatonnes of GHG emission reductions, depending on the utilization rate of that line and whether non-emitting electricity in that instance was directly displacing coal, which has a higher greenhouse gas intensity, or natural gas, which has a significantly lower greenhouse gas intensity.