Australia's federal government has proclaimed "geosequestration" as its preferred method of tackling greenhouse gases and global warming. Geosequestration, an as yet unproven technique for reducing carbon emissions, involves capturing the carbon dioxide released when materials such as coal are burned, compressing it into a liquid and injecting it underground where it stays for thousands of years. The federal government argues this is more cost-effective than investing in renewable energy technologies such as wind power. Critics note the decision means Australia will inevitably rely on fossil fuels well into the future. Environment groups, angered by the announcement, say the untested technique is already receiving hundreds of millions of dollars of research subsidies.