Existing fossil-fuelled power plants will emit 300 billion tonnes of carbon dioxide during their lifetime, and with new facilities coming on stream each year the combined affect will be the release of significant quantities of greenhouse-gas emissions into the atmosphere, according to a study published in the science journal Environmental Research Letters.
Research scientists, Steven Davis of the University of California and Robert Socolow of Princeton University found that the number of new power stations coming online is growing at a faster rate than those being retired. "Bringing down carbon emissions means retiring more fossil fuel-burning facilities than we build," said Davis, the study's lead author. "But worldwide, we've built more coal-burning power plants in the past decade than in any previous decade and closures of old plants aren't keeping pace with this expansion."
According to the researchers, the predicted lifetime CO2 emissions from existing power plants, though representing a substantial portion of the global GHG emissions budget, would not be sufficient to increase global temperatures by more than 2ºC relative to the preindustrial era. But, they warn that future committed growth in such facilities worldwide is not fully accounted by the UN’s global GHG accounting methodology. "We are flying a plane that is missing a crucial dial on the instrument panel," said Socolow. "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."
The researchers used a “commitment-accounting” technique to quantify the total emissions of a power plant over its probably lifetime – linked to capital investment decisions made today. This reveals that the fossil-fuel-burning power plants built worldwide in 2012 alone will produce roughly 19 billion tonnes of CO2 over their lifetime, assuming the plants operate for 40 years. This is considerably more than the 14 billion tonnes of CO2 emissions produced by all the plants operating worldwide in 2012. The research reveals that between 2010 and 2012, the world added 89 gigawatts (GW) of new-coal-generating capacity a year, 23GW a year more than from 2000 to 2009, and 56 GW a year more than during the period 1990 to 1999.
Fossil-fuelled power plants in the US and Europe, which account for about 11% and 9% of committed emissions respectively, have been steady or declining in recent years, says the report. However, investments in new facilities in developing countries, where there is rapid economic growth, will increase future worldwide GHG commitments. Power plant construction in China, which accounts for about 42% of committed future emissions, has slowed in recent years, but south east Asia has been building more to expand its industrial capacity. Coal-fired power stations account for about two-thirds of these emissions. "Far from solving the climate change problem, we're investing heavily in technologies that make the problem worse," said Davis.
