I found this very informative article on CSM in Australia, well worth a read. I have pasted some points below.
"In the third quarter of 2007, CSM production grew by 34.1% to reach a total of 28.8PJ for the quarter and 103PJ for the 12 months to the end of September, 16.3% of east coast production."
"Queensland gas electricity certificates policy has encouraged CSM. The GEC scheme – announced in 2000 and introduced from January 1, 2005 for 15 years – requires Queensland power companies to source at least 13% of their electricity from gas-fired generation. (This has now been scheduled to increase to 18% from 2020). More than half of CSM production is contracted for power generation."