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This article is from the In-Depth Report The Future of Climate Change

Climate Talks Prove Growing Need for Carbon Capture and Storage Globally

Without technology to capture CO2 and store it safely and permanently, climate change cannot be constrained



Kate Sheppard

DURBAN, South Africa—The roughly 3,000 fossil fuel–fired power plants in North America—Canada, Mexico and the U.S.—emit 6 percent of global greenhouse gases, or nearly as much as all of the European Union. In fact, coal-fired power plants around the globe are the single largest source of greenhouse gas emissions.

In other words, coal is largely responsible for climate change. Burning coal alone contributes more than half of global greenhouse gas emissions from human activity. "Whatever you hear from time to time, a big part of electricity is produced from coal," argued Philippe Joubert, deputy CEO of power equipment manufacturer Alstom at the climate talks here on December 6. "This will continue."

That's why so-called carbon capture and storage (CCS) is a mark of seriousness in efforts to combat climate change; Joubert calls it "mandatory." Because the world seems to have little interest in restraining coal burning—it continues to increase, driven largely by China and India—capturing the CO2 before it enters the atmosphere is the only real way to tackle such emissions.

"There are more than enough discovered hydrocarbons to fry the planet," Lord Nicholas Stern of the London School of Economics and Political Science told Scientific American. "You can do CCS or you can bust two degrees [Celsius of warming]."

That is why the negotiations here in Durban approved CCS as a potential technology under the Clean Development Mechanism—a way to provide funds from developed to developing countries for emission-reducing infrastructure in return for credit against the developed countries' CO2 emission quotas. Unfortunately, the mechanism is a part of the Kyoto Protocol. And the protocol will expire at the end of next year without a successor—unless one is agreed on this week in Durban.

Regardless, the world seems to be closing down more CCS plants than it opens: The E.U.'s flagship CCS project at Schwarze Pumpe was cancelled on December 5 due to local German opposition. Canada has had a CO2-sequestration project running for years now in the Weyburn oil field in Saskatchewan but has yet to expand operations to the tar sands that are single-handedly increasing that country's emissions—which violate its obligations under Kyoto. U.S. power company AEP recently turned down the opportunity to expand the world's first project to combine CO2 capture and storage at one site—Mountaineer in West Virginia. China, the world's largest emitter largely because of its coal burning, has a few pilot projects and is considering more.

Even more importantly, whereas China may be able to afford CCS, other developing countries like South Africa certainly cannot at a price of roughly $1 billion to add the technology to a one-gigawatt coal-fired power plant, per Brad Page, CEO of the Global CCS Institute in Australia. And South Africa consumes a lot of coal, generating 92 percent of its electricity and exporting $10 billion worth to Europe and China—even turning it into 30 percent of the diesel for trucks and jet fuel that it uses domestically.

In South Africa's bid to continue economic growth—and spread electricity to the more than 2 million South Africans who currently lack it—the republic is building more coal-fired plants. In fact, national utility Eskom recently received a $3.75-billion loan from the World Bank to build six 800-megawatt coal-burning units at the Medupi power plant in Limpopo Province as well as much smaller renewables projects.

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.

Asked if the world is taking carbon capture and storage seriously, Lord Stern responds "Not seriously enough. This is a moment we need to ramp up. … We are moving into territory where 3 degrees [Celsius of warming] is quite likely, and we haven't been there since three million years ago," or before modern humans—and certainly modern human civilization—existed.

"The most important thing that countries have to do is to take steps to progressively transform the energy base of their economy," said U.S. climate envoy Todd Stern during a press briefing on December 8. " You need to use less energy through efficiency and to develop renewable energy sources more." But even if such efforts are successful, the U.S.—and the world—will also need carbon capture and storage if it is to meet the goal of keeping global average temperatures from rising to dangerous levels.

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