Carbon Sequestration – an optimal clean technology?

While coal-fueled power plants are directly responsible for roughly one-third of our CO2 emissions, the DOE indicates that coal is expected to dominate our domestic power generation at least for the next 25 years.  Globally, the increased demand for coal-fueled electricity will translate into a 57% rise in related CO2 emissions by 2030 according to the IEA.

One technology that attempts to solve the CO2 emissions crisis is carbon capture and storage, or CCS. Generally speaking, CCS captures the CO2 emissions from coal power plants and other industrial sites and injects the CO2 into underground porous rock formations in hopes of permanent sequestration.

Both the coal industry and the Obama administration endorse CCS.  Obama supported $3.5 billion for CCS of the $787 billion Stimulus Package and has made CCS a cornerstone of renewable energy policy.

“To prevent the worst effects of climate change, we must accelerate our efforts to capture and store carbon in a safe and cost-effective way. This funding will both create jobs now and help position the United States to lead the world in CCS technologies, which will be in increasing demand in the years ahead,” said Energy Secretary Steven Chu a few weeks ago.

Of course, the coal industry has a vested interest in promoting “clean” energy solutions that provide for continued use of and dependence on coal. But is CCS an optimal cleantech solution?

It’s expensive – conventional coal-fired plants are not configured to support the CCS solution. No CCS plants currently exist on a large commercial scale.  Plants that would readily support CCS by converting coal into gaseous form to allow capture of the CO2 emissions before gas is burned are very costly.

The CCS process is energy intensive itself – adding upwards of a 30% energy penalty to the production of electric power.  Thus, CCS perversely compounds the carbon problem it is intended to correct.

Further, questions remain as to the permanence and safety of sequestration.  Though generally not regarded as a toxic substance (apart from climate change impacts), CO2 if released into groundwater or the atmosphere can have harmful if not deadly effects. Most CCS experts agree that up to 20 demonstrations to test the technology would be required to ensure that safety concerns are addressed adequately, adding to the expense and delay of CCS commercial deployment.

CCS may be creating more jobs, but is this the best way to deal with coal’s effect on climate change?  What is the opportunity cost of CCS?  By pursuing CCS and our continued reliance on coal, are we making an investment that would better be made on technologies that themselves are clean?

[photo: flickr/davipt]