Clean Coal?
Paul Kando
Back in 1925, the late scientist Maria Telkes, my mentor at the University of Delaware’s solar research laboratory, saw a coal miners’ memorial in Brussels. Such back-breaking work, such dirty energy!
she reminisced. I knew I had to dedicate myself to finding an alternative
. The memory comes to mind whenever “clean coal” is mentioned as a solution to U.S. energy needs.
photo credit: undark.com
A 2007 National Academy of Sciences study criticized systematically inflated national coal reserves figures, concluding that there is probably sufficient coal to meet the nation’s coal needs for maybe 100 years. Another study suggested a strong likelihood of global coal supply limits appearing within the next two decades.
The U.S., China, Britain, and Germany have all already mined their best coal resources, with the remainder difficult and expensive to extract. Likewise, coal production in the Eastern United States has been declining due to the depletion of economically minable reserves. Wyoming and Montana hold much of what’s left. However 94% of reserves claimed by the mining industry and the U.S. Energy Information Agency are too expensive to extract.
What about “clean coal”? The technology to capture carbon emissions from coal-fired power plants has been tried and tested, yet almost none of the nation’s coal-fueled power plants are “clean” because the economics don’t work. Carbon capture and storage (CCS) is expensive. Depending on the approach, capturing and storing the carbon from coal combustion consumes an estimated 25 to 45 % of the power produced,. That means higher priced coal-generated electricity and a need for more power plants to serve the same customer base. Technologies that would make CCS more efficient aren’t yet commercial, and their costs are unknown.
Furthermore, capturing and burying just one third of the carbon released from current U.S. coal combustion would involve an infrastructure of pipelines, compressors and pumps on a scale on par with the oil industry. And while it is possible to retrofit existing power plants with CCS technology, it is not efficient. A new generation of plants would do a better job, but that would mean replacing roughly 600 current-generation power plants.
For these reasons, the Energy Department estimates that wholesale electricity prices using current generation CCS technology would be 70 to 80% higher than current coal-based power—which itself is already uncompetitive with natural gas, wind, or new solar PV. Meanwhile the price of electricity produced by solar and wind continues to fall. The only thing that keeps coal-based electricity competitive with renewable energy sources is the industry’s ability to externalize coal’s hidden environmental and health costs.
Coal just isn’t “clean.” And CCS doesn’t eliminate all the pollutants from the combustion process either, nor deal with the coal dust from mining and transport. It also doesn’t address the environmental devastation of “mountaintop removal” mining. Our real future lies with distributed renewable energy and substantial reductions in overall energy consumption through efficiency measures and a redesign of the economy. The inevitable transition away from fossil fuels is a big job that only gets bigger and more costly the longer we delay.