The CPRS is increasingly looking like the answer to a question that nobody asked, namely, what would be the best way to introduce a complex and expensive national scheme that sounds like a solution to climate change without really changing anything?

But as the Senate vote gets closer, the first question that Climate Change Minister Penny Wong must answer is: if the Carbon Pollution Reduction Scheme (CPRS) doesn’t increase the cost of transport fuels, doesn’t apply to agriculture and, as Treasury modelling shows, doesn’t lead to a reduction in our reliance on coal-fired electricity until at least until 2033, what does it actually do?