LOW CARBON LIFE
Coal is the dirtiest of all fossil fuels. NASA climate scientist James Hansen has described coal power stations as 'factories of death' because coal is the greatest source of global CO2 emissions (53% in 2011) and it's continued use will cause the extinction of many animal and plant species that cannot adapt to higher temperatures.
Hansen has lobbied the governments of the three countries which have emitted most CO2 over the last two centuries (in order: USA, UK and Germany) to stop building coal-fired power stations. If we stopped turning coal into electricity, Hansen says the concentration of CO2 in the atmosphere would fall to 350ppm (the target that he says would prevent temperatures rising more than 2˙C).
Coal interests have political support in Washington and other capitals. Hansen points out that we need a moratorium and phasing out of coal power stations, but this will depend on public demand and the political will. So far, these do not exist and although carbon capture and storage can theoretically deliver clearn coal, it is decades away from being cost-effective reality because there is currently no effective financial incentive to invest in hugely expensive research and development.
In 2010, China overtook the USA as the country with the highest national CO2 emissions and most of its electricity comes from coal. However, both the USA and China are now turning to gas power stations, which emit less than half the CO2 of coal per unit of electricity.
An article in the New York Times by Andy Revkin considers the implications of a revolution in natural gas supplies due to shale fracking. http://dotearth.blogs.nytimes.com/2012/07/04/a-greenhouse-gift-if-china-follows-u-s-shift-from-coal-to-gas/
Regulatory changes in the USA sparked investment in research and technology for fracking. The vast reserves of gas opened up by fracking has caused the price of gas to drop. Ten years ago, coal provided around half of US electricity, with gas providing around 15%. By April 2012, the share of electricity generated from gas and coal were equal at 32%. The speed of this shift is remarkable given that coal accounted for an average of 42% of US electricity in 2011. It may be too soon to know if this trend will continue and there are concerns about its environmental impact of shale gas fracking, but it also looks set to reduce China's dependence on coal.
However, James Hansen's concern is still valid. Coal is still driving economic growth in China and will remain the core energy source in many countries for decades to come, unless public concern becomes too strident for politicians to ignore.