Much to the scepticism of our readers we’ve covered hot rocks at least once or twice before. In a nutshell, it’s a form geothermal energy derived from pumping water kilometres underground where it gets heated enough (by hot rocks!) to then rise back to the surface and drive turbines. Taking time off from phasing out incandescent light bulbs, the Australian government’s Environment Minister, Malcolm Turnbull reckoned that ‘large-scale geothermal power plants had the potential to substantially reduce Australia's carbon dioxide emissions and could provide up to 10 per cent of the country's electricity needs by 2050.’ His counterpart in the Industry Ministry, Ian Macfarlane, was meanwhile giving $5 million AUD to exploration company Petratherm to investigate the concept further at their test site in South Australia’s Flinders Ranges. 200 jobs are due to be created as a result. Another company with a potential hot rocks site in the same state is GreenRock Energy, but it looks as if their eyes are currently focussed on a project in western Hungary. It’s all still a bit experimental at the mo’, but makes for a welcome and cleansing relief from the barrage of so called solutions of ‘clean coal’, CO2 geosequestration, and nuclear. ::Petratherm, via SMH.