That's the kind of technology "lock-in" that the International Energy Agency (IEA) warned about in its latest World Energy Outlook, which states that heavily polluting coal-fired power plants must stop being built in the next five years if there is to be any hope of restraining greenhouse gas emissions. Once too many coal plants are built, such as in China, which has built hundreds in the last decade, it is highly unlikely that they will be shut off prematurely. "CCS is one option for us in China," notes Liu Qiang of the Energy Research Institute in Beijing, which is affiliated with the National Development and Reform Commission, the government agency charged with setting Chinese energy and industrial policy. "Now it is still in the stage of R&D," or research and development.
And then there's heavy industry—steel manufacturing, cement making and other industrial pursuits have no alternative but to the use of fossil fuels, particularly coal. They are also the fundamental substrate of global infrastructure—from buildings to renewable energy projects, such as wind farms. "For industry, the key word is really CCS—we can only go so far with energy efficiency," notes Laura Cozzi, principal analyst in the office of the chief economist of the IEA. "We are miles away from having deployment of CCS."
The world currently has eight carbon-capture or storage projects and an additional six under construction that would deliver (if built) some 33 million metric tons of captured CO2—or more than the entire CO2 reduction effort of the U.K. government, according to the Global CCS Institute's Page. "It doesn't take many of these projects to make a big difference," he adds. Yet, the IEA projects that the world will require 3,000 such ventures by mid-century.
Two of the six projects under construction are in North America—the coal-gasification complex in Kemper County, Miss., will capture 65 percent of its CO2 emissions and sell much of the CO2 that is used for scouring oil out of the ground in the Gulf Coast region. The Boundary Dam power utility in Saskatchewan will capture 90 percent with an amine solvent, albeit from a much smaller facility, and then deliver that CO2 to recover additional oil in nearby fields.
Current cost estimates from the Global CCS Institute in Australia suggest that such projects capture and store CO2 at a cost of between $23 and $92 per metric ton, while also noting that such prices are expected to drop if and when actual full-scale CCS capacity is built. That cost is presently offset by either selling the CO2 to enable more oil to be extracted from old fields—with attendant climate impacts—or through government subsidies, in the absence of a price on the emission of greenhouse gases. Then there's the energy penalty—running the CCS equipment consumes roughly 20 percent of the electricity produced by the power plant.
Capturing CO2 is the easy part—if expensive: the emissions of a coal-fired power plant are simply filtered through amines, chilled ammonia or other chemical-capture agents to bind the CO2 and remove it from the flue gas. But subsequent storage is proving to be a significant hurdle. Germans, for example, rejected efforts to build a CO2 pipeline between the Schwarze Pumpe power plant and a potential geologic sequestration site. Storage of the CO2 "is proving to be very challenging," notes Vijay Iyer, director of the World Bank's sustainable energy department.
Power plants and other large sources are also not necessarily built atop the right kind of geologic formations to permanently store CO2. Pipelines will be needed. Although there are more than 6,000 kilometers of CO2 pipeline already operating in the U.S., transporting CO2 from sources to sequestration sites could require as much as 120,000 kilometers of such pipelines globally.