Serious flaws have been found in a decade's worth of studies about the best way to reduce greenhouse gas emissions and stabilize the climate.
The findings, from the University of Michigan, are released as world leaders at COP21 attempt to negotiate the globe's first internationally binding climate agreement.
The U-M researchers have found that most economic analysis of carbon capture and storage, or CCS, technology for coal-fired power plants severely underestimates the technique's costs and overestimates its energy efficiency. CCS involves sucking carbon out of coal-fired power plants' flue gases, compressing it and then injecting it deep underground.
The new analysis puts the cost of reducing carbon emissions with CCS-equipped coal plants higher than any previous study -- and most importantly, higher than wind and comparable to solar power. It's the first study to confront the so-called 'energy loop' inherent in the CCS process.
Beyond a one-time 'energy penalty' these plants pay because they have to burn more coal to power devices that capture carbon, the researchers say the disadvantage compounds until fuel costs leap to four times today's accepted estimates.
"The conclusion is that renewables will be a cheaper alternative to reducing carbon emissions from coal, at least in the United States and likely globally," said Steve Skerlos, U-M professor of mechanical engineering, and civil and environmental engineering.
"To us, this means policymakers need to stop wasting time hoping for technological silver bullets to sustain the status quo in the electric sector and quickly accelerate the transition from coal to renewables, or possibly, natural gas power plants with CCS."