I’m planning a full-length post on Garnaut, but I thought I’d do a quick check on what would be involved in meeting the target of a 10 per cent reduction in emissions between 2000 and 2020. My guess is that the increase in oil prices we’ve already seen will be enough to bring consumption of petrol and diesel back to the 2000 level, and that other sectors like agriculture will be roughly stable. That means that most of the reduction will have to be found in energy generation.
My rough estimate is that the use of brown coal in energy generation contributes around 10 per cent of total emissions (Update:After I revised my estimate to 15 per cent, reader Chris Short pointed me to a section of Greenhouse Gas Inventory I’d missed, which gives brown coal a 30 per cent share of electricity’s 34 per cent of emissions, so 10 per cent was right ), so, as a first approximation, the Garnaut target could be met shutting down the brown coal sector and replacing it with enough renewables to cover the brown coal share of existing electricity, and any growth in final consumption. Consumption growth would be constrained both by increasing prices and by conservation measures.
That would certainly require a substantial adjustment assistance program in the Latrobe valley and similar locations. We’ve done this kind of thing before, for example, with the end of the steel industry in Newcastle, sometimes well and sometimes poorly.
My guess is that the actual outcome would involve keeping some brown coal stations, with drying technology that reduces emissions to a level comparable with black coal, and some expansion of gas-fired power stations, offset by a combination of domestic offset measures and purchases of international offsets. The Garnaut cost estimates of around 1 per cent of GDP look pretty plausible for this. This story actually suggests a lower value, since $35 billion over 10 years is around 0.3 per cent of GDP.