Clean Coal, a Global Failure in the Making

Last Updated Nov 3, 2009 1:28 AM EST

Here's a bit of unalloyed pessimism for you: Carbon capture and sequestration, more widely known as clean coal technology, is not going to work out. Governments and the coal industry are trying to bite off too much at once.

In theory, clean coal is a fine idea. The process of burning coal releases gases, which all modern plants already "scrub" of harmful substances like sulfur dioxide. To fight global warming, coal mine and plant owners want to do the same for carbon dioxide.

Sounds great, except that a fairly average-sized 1,500 megawatt coal plant produces about three billion tons of CO2 yearly (update: This figure is closer to yearly emissions from all U.S. coal plants. A reader notes that the correct number is around 12 million tons per year, per plant.) . All that CO2 has to be separated out, a process that uses up a lot of the energy the plant produces. Then, according to current thinking, we must bury the CO2 and hope that it doesn't come back up.

That's a hell of a challenge. A report released Thursday by the pro-CCS Global Carbon Capture and Storage Institute helps outline just how much. A few bullet-points:

  • Clean coal research is currently moribund; only seven CCS projects exist today, and all are attached to gas plants
  • The GCCSSI expects national governments to coordinate to give $100 billion yearly to CCS research
  • Provided the money is forked over immediately, we might have 20 plants by 2020
  • And if those initial plants work out as expected it will take until 2030 to have a significant number operating
  • If the technology works as expected, it will add an average of 78 percent to the cost of electricity from coal
Anyone familiar with the basics of risk wouldn't bet on that many "ifs", especially given the looming difficulty of not only coaxing governments to throw trillions of dollars into research, but also share the technology as it develops.

Nevertheless, everything could work out perfectly and clean coal could be spreading in 2030. By that time, CO2 concentrations in the atmosphere may be over 500ppm. That's no problem if the climate change skeptics are right; if the 97 percent of climatologists who study climate change are right, that number would mean we're in for some major upheaval.

In other words, we need better solutions, right now. For coal, there are already some available. Old, inefficient plants can be shut down in favor of new ones that operate at a much higher thermal efficiency, and work onnew concepts like underground coal gasification could be accelerated.

The $2.4 trillion the International Energy Agency says we should spend researching clean coal sould also be spent other ways; research and investment into renewables like geothermal and solar power come to mind, and it's also enough money to buy several hundred nuclear plants.

If we do insist on clean coal, the concept needs a rethink. Trying to figure out the most cost-effective way to scrub CO2 is enough of a challenge. The additional problem of permanently sequestering it underground adds too much expense and uncertainty.

There are better ways. One would be to use the CO2 to create liquid fuels for transportation. Oddly, this idea is rarely brought up in the debate over clean coal, although scientists are already working on ways to use CO2 they captured from ambient air for fuel.

It's a more energy-intensive process (read: expensive) process to capture CO2 from the air around us than the flue of a coal plant, where it's already highly concentrated. But the attitude toward CO2 from coal is that it must be buried, because it's new to the atmosphere -- nevermind whether the fuel could replace a petroleum product, which also emits new CO2.

But the thinking on clean coal is, for the moment, quite rigid. One can only hope that, in the wholesale rush toward what seems immediately sensible, we don't forget one of our best weapons -- creativity, and adaptation to new circumstances.