There are more cows than people here in Nirranda South, three hours south-west of Melbourne, making it the perfect spot to test a technology that remains hugely controversial. I am at a facility run by Australia's Cooperative Research Centre for Greenhouse Gas Technologies (CO2CRC). If anyone can convince the public that carbon capture and storage can reliably reduce carbon dioxide emissions it's these guys. Even Friends of the Earth, Australia - which opposes the approach - has grudging respect for the research done here.