In 2015 international oil company Shell will begin to capture more than one million metric tons of the odorless, colorless gas known as carbon dioxide. The CO2 will come from three enormous machines near Fort Saskatchewan, Alberta, that produce hydrogen to turn bitumen into salable oil. Once captured, the CO2 will be pumped through a pipeline to a site where it will be buried more than two kilometers underground in a porous sandstone formation. This carbon-capture-and-storage project, dubbed Quest, will be the first in the world run by the oil production industry—and join a short list of working demonstrations of a technology that may be vital if humanity is to avoid catastrophic climate change.

Carbon capture and storage (CCS) "is the quickest way to get substantial greenhouse gas reductions," argues Len Heckel, Shell Canada's commercial lead for the Quest project. Heckel suggests that Shell and its partners undertook the project to reduce the company's carbon footprint, advance the technology and take advantage of government funding.

But the Quest project is a rare example of a technology that seems stuck, much like the CO2 after it is pumped underground. The 2012 survey by industry group the Global CCS Institute found that although nine new projects were announced this year, eight previously announced ones failed, bringing the total number of CCS projects worldwide to 75. Of those 75, eight are in actual operation, storing some 23 million metric tons of carbon dioxide per year—or slightly more than the annual emissions of Bahrain—most of it from the processing of natural gas to remove CO2 so the fuel is ready to burn.

Despite the slow start, "CCS is an existing, real technology today," argues institute CEO Brad Page, adding that it is needed to meet any global goal to restrain global warming cheaply. The International Energy Agency estimates that the world needs more than 100 operational CCS projects—storing some 270 million metric tons of CO2 annually—by the end of this decade to keep global warming from surpassing a 2-degree rise in global average temperatures, given that more than 80 percent of the world's energy continues to come from fossil fuels. Or, as Page adds, it's about economics: "At stake is a very substantial power bill for the world's energy consumers if we don't get CCS up and running by 2050."

China prize
The U.S. was once the world leader in CCS experimentation, ranging from injecting CO2 underground to scour oil out of old wells to running the world's first combined carbon-capture-and-storage unit at the Mountaineer power plant in West Virginia. But Mountaineer's experiment came to an end in 2011, thanks to an inability to get customer-sourced funding approved by local regulators, given an absence of national legislation to restrain greenhouse gas emissions. "The hardware is still untapped," says chemical engineer Gary Spitznogle, director of new technology development and policy support at American Electric Power, the utility that owns and operates the Mountaineer coal-fired power plant. "We shut it down and laid it up in case someone wanted to reuse it."

That's not likely to happen anytime soon—or as Spitznogle puts it: "There'd have to be a reason more than just a deep scientific fascination with doing it." New projects are underway in the U.S.—the Plant Barry project in Alabama is capturing CO2 and burying it in an old oil field, and a new coal-fired power plant with CCS is being built in Kemper County, Miss. But progress on CCS for coal-fired power plants in the U.S. has slowed for one major reason: natural gas.

Coal plants are shutting down because of a rise in the availability of cheap natural gas, largely as a result of hydraulic fracturing, which is opening up new deposits of the fuel in places such as the Marcellus Shale Formation in Pennsylvania. That's good news for the global climate because burning natural gas emits roughly half as much CO2 as burning coal. But it's also bad news for the climate because burning natural gas still emits CO2. "There are more than enough discovered hydrocarbons that if we burn them, we fry the planet," Lord Nicholas Stern told this reporter at the Durban climate conference last December while discussing carbon capture and storage. "You can do CCS or you can bust the 2-degree target."

As a result of the shale gas revolution in the U.S., the bulk of new CCS projects worldwide are in China, which hopes to become a leader in the technology. Carbon capture and storage even snuck into the Communist Party's 12th Five-Year Plan. Eleven projects are under development across the country, ranging from advanced coal-fired power plants to a chemical plant that will turn coal into liquid fuel.

The Chinese are even considering investing in a CCS project in Texas, known as the Texas Clean Energy Project. But the key there, as in most ongoing projects, is not a price on CO2 pollution that emitters want to avoid, but a price on CO2 that is used to help get more oil out of the ground—a process known as "enhanced oil recovery," a potentially large market given the world's thirst for petroleum.

Oil to the rescue?
Carbon dioxide is already used to scour hard-to-reach oil below Texas. But it is pumped more than 800 kilometers in a pipeline from a naturally occurring formation of CO2 in Colorado, which can prove expensive. CO2 from a nearby CCS unit might lower the price of CO2, storing some of the greenhouse gas underground as a kind of unintended side benefit.

Such enhanced oil recovery can also be done with steam, of course, which is why breakthroughs on the capture side are still required to make CO2 even cheaper. That work spans everything from Advanced Research Projects Agency–Energy projects to an X PRIZE Foundation effort to raise the money to launch a carbon-capture prize, according to Christopher Frangione, senior director of the energy and environment prize group for the foundation.

Making capture cheaper is particularly needed when the process is applied to natural gas power plants. As it stands, U.S. Environmental Protection Agency greenhouse gas emission limits for new power plants are set at the level of the discharge of a new gas-fired power plant, thus there is no regulatory incentive to put CCS on a gas plant. But at some point that technology will be needed if the world is to avoid increasing greenhouse gas concentrations in the atmosphere, which is why France-based CCS technology provider Alstom is investigating it at its Mongstad facility in Norway. The chilled ammonia process from the Mountaineer demonstration will be used to capture CO2 from burning natural gas. "The technology is there and it can be done," argues Bob Hilton, vice president for government affairs at Alstom.

In the meantime, the only combination driving the technology forward seems to be CCS for enhanced oil recovery, although oil isn't exactly a carbon-neutral fuel. Hence the $1.35-billion Shell CCS project in Alberta, with the Albertan and Canadian governments footing more than half of the bill in exchange for the sharing of data and lessons learned.

The project will use the same amine chemistry employed by Shell since the 1950s to separate CO2 and other impurities out of natural gas. Methyl diethanolamine absorbs the CO2 and then releases it when heated, an energy-intensive step and a major reason why CCS remains uncommon. The CO2 captured will represent roughly 35 percent of the greenhouse gas generated by the entire operation.

The plan is to inject the captured CO2 into sandstone dating back to the Cambrian period, for at least 25 years. "There are no plans for Shell to get involved in [enhanced oil recovery] for Quest," Shell's Heckel says. After all, another CCS project in the Albertan tar sands was shelved in April of this year because of a lack of buyers for the captured CO2, according to that project's backers.

Lack of a market will continue to slow any bid to construct 100 CCS projects by the end of this decade. The CCS Institute's Page argues that "it's not a technology that's dead, it's alive. It is moving ahead but it faces some headwinds." Yet such buffeting suggests that the technology may develop and deploy too slowly to significantly combat climate change.

"When we finally do deploy, we'll have to deploy it faster, but that's not beyond reason," Alstom's Hilton argues. "I'm still very optimistic industry can do this." If the world likes coal, oil or even natural gas and wants to continue burning fossil fuels, carbon capture and storage may be the only way to slow the increase of greenhouse gas concentrations in the atmosphere at the same time.