Fossil fuel
Existing coal power plants are committed to pumping out 300 billion tons of CO2 during their lifetimes.Reuters

Taking into account all existing fossil fuel based power plants around the world, the world is "committed" into pumping out more than 300 billion tons of carbon dioxide over their expected lifetimes.

A high-carbon future is being locked in by the world's capital investments, warn researchers at Princeton University and the University of California-Irvine.

They point out that the world's accounting system for carbon emissions does not include capital investments in future coal-fired plants and natural-gas power plants. These plants will commit the world to several decades and billions of tons of greenhouse gas emissions, according to UCI.

For the first time, researchers have developed a "commitment accounting" that assigns all the future emissions of a facility to the year it begins working.

With 'committed' emissions growing by 4% every year as more plants are built, and assuming these plants will operate for 40 years, projections show the power plants constructed globally in 2012 alone will produce about 19 billion tons of CO2 during their existence.

This is considerably more than the 14 billion tons of CO2 emissions produced by all the plants operating worldwide in 2012.

The findings appear in the August 26 dated issue of the journal Environmental Research Letters.

"Bringing down carbon emissions means retiring more fossil fuel-burning facilities than we build," said Steven Davis, assistant professor of Earth system science at UCI and the study's lead author. "Far from solving the climate change problem, we're investing heavily in technologies that make the problem worse."

While some old plants are being closed down, closures are nowhere near the expansion of the coal plant fleet.

Davis and co-author Robert Socolow of Princeton suggest the findings could be used by policymakers to evaluate the long-term climate impact of current investments in infrastructure. "We are flying a plane that is missing a crucial dial on the instrument panel," Socolow said.

"The needed dial would report committed emissions. Right now, as far as emissions are concerned, the only dial on our plane tells us about current emissions, not the emissions that current capital investments will bring about in future years."

Power plants now operating in the US and Europe account for about 11% and 9% of committed emissions, respectively. However, the study notes that these commitments have been steady or declining in recent years. But the developing world has picked the baton with a spurt of new plants in China, India, Indonesia, Saudi Arabia and Iran.

Plants in China and India represent 42% and 8% of committed future emissions, respectively. About two-thirds of these emissions from the power sector are due to coal-burning stations.

Beijing recently announced it will stop using coal and its related products, and close coal-fired power plants and other coal facilities by 2020 in six of its capital districts. Chinese policy to replace existing coal-fired plants with new, larger, more efficient coal-fired plants and modern coal-fired power stations have cut carbon emissions by 30 per cent, say experts.