the total system costs include also the complete list of nonmonetised externalities that are not mediated by the electricity grid and that affect a country s wider economy and wellbeing beyond the electric power system itself to the extent that such externalities are monetised and emitters are held responsible for their emissions they can also be integrated into plantlevel cost accounting the edition of the projected costs of generating electricity ieanea thus imputed a tax of usd per tonne of c on the emissions of fossilfuel based generators