The Morrison government doesn’t know how much investment would be needed to achieve the emissions reduction goal through its technology road map.
The road map highlights five key low emissions technologies and sets price goals for them, in a bid to make them economically desirable.
But a Senate estimates hearing on Tuesday was told there’s no time frame for the goals and the department hasn’t calculated how much it would cost.
Department of Industry, Science, Energy and Resources deputy secretary Jo Evans said the issue was approached in terms of how much technology would be deployed if the price goal was met.
“So we haven’t necessarily backed that out to imply how much investment was that going to take,” she said.
Government minister Simon Birmingham defended the decision, saying costing would need constant re-evaluation.
“To try to put the type of figure you’re seeking in relation to such a long time frame of quite variable steps to get there, is not a particularly practical objective to seek at this point in time,” he told Labor senator Jenny McAllister.
The government says the price goals would result in emissions reduction of 250 million tonnes a year by 2040.
But that’s a global figure and it’s unknown how much of it is for Australia.
Senator McAllister asked what reduction would be achieved through the plan by 2030, with officials promising to provide the analysis later.
Officials have struggled to define clean or low emissions technology, as referred to in the road map.
“If it’s very low and close to zero then you’re essentially clean,” Ms Evans said.
“That’s as far as we could get, in the group of quite eminent minds who put themselves towards thinking about how can you talk about this in a sensible way.”
Australia’s emissions are expected to be higher than initially calculated because of the Paris agreement’s rules.
It puts a higher global warming potential on methane, resulting in it being the equivalent of more carbon dioxide.
Ms Evans said the emissions budget would also change to reflect the rules.
Greens senator Larissa Waters was unimpressed.
“I can see how that might flow logically from an accounting perspective but we’ve just been advised that methane is more damaging to the climate than we realised,” she said.
“Are you really saying the response is to say we should be able to pollute more, rather than doing the opposite and realising that we need to take stronger action?”