Turning Carbon Dioxide into an Asset
04 Mar, 2012
With global greenhouse gas emissions still on the rise, despite decades of talk about curbing them, maybe the time has come to think differently about the climate crisis. Yes, we need to burn less coal, oil and natural gas, but clearly fossil fuels are going to be around for awhile. So why not try to clean up the mess they make?
That’s what a handful of prominent scientists are trying to do by developing technologies to remove carbon dioxide from the air. These scientists have launched start-up companies and attracted well-to-do investors — most notably Bill Gates — along with venture capital and, most recently, the attention of Wall Street. They say their technology does not need government support, though it would help. What it needs, above all, is a mindset that regards CO2 not simply as a pollutant but as a valuable commodity.
Nathaniel “Ned” David, the chief executive of a startup called Kilimanjaro Energy, puts it this way: “The single largest waste product made by humanity is CO2. Thirty gigatons a year. It’s immensely valuable, and today we just blow it out the tail pipe. What if there were some way to actually capture it, use it, and make money?”
Carbon dioxide removal, or CDR, is sometimes seen as a subset of geoengineering — deliberate, planetary-scale actions to cool the Earth — but it’s actually quite different. Geoengineering strategies are risky, imperfect, controversial, and difficult to govern. The most-discussed geoengineering technology, solar radiation management, alleviates a symptom of the climate problem (warmer temperatures) but does nothing to address the cause (rising atmospheric concentrations of CO2). What’s more, geoengineering as a climate response is stuck because governments have declined to provide more than token funds for research, and there’s no business model to support it.
Carbon dioxide removal, by contrast, targets the root cause of global warming. It doesn’t create global risks. It’s being financed by the private market, and it’s more akin to recycling waste than to playing God with the weather.
Despite widespread skepticism in the scientific community, three startup companies are betting that they can make money by recycling CO2, and thereby cool an overheating planet. Kilimanjaro Energy is the pioneer. The company was launched in 2004 by Klaus Lackner, a Columbia University physicist who first wrote about air capture of CO2 in a 1999 paper. It was initially financed with $8 million from Gary Comer, the founder of Land’s End, who grew concerned about climate change after he sailed a yacht through the normally ice-bound Northwest Passage with relative ease. (Comer died in 2006.) Last year, Kilimanjaro raised another $3.5 million from a venture firm called Arch Venture Partners.
Global Thermostat, a second startup, also took root at Columbia. Its founders are Peter Eisenberger, a former head of research for Exxon who started Columbia’s Earth Institute, and Graciela Chichilnisky, who holds dual Ph.Ds in economics and math. Edgar Bronfman Jr., the former Warner Music CEO and heir to the Seagram’s fortune, has put $15 million into the venture, and a big private equity firm is in talks with the founders about taking a major stake in Global Thermostat. (Eisenberger and Chichilnisky wouldn’t identify the investor.)
Global Thermostat has built a small demonstration plant at SRI International in Menlo Park, Calif., that today is sucking carbon dioxide from the air. About the size of a two-story elevator shaft, the pilot module sucks air past porous ceramic blocks known as monoliths, where amines bind with the carbon dioxide; the blocks are then lowered into a chamber where they are flooded with steam that releases the CO2, and the process then repeats itself.
Finally, there’s Carbon Engineering, a startup run by David Keith out of Calgary, Alberta, the nerve center of Canada’s oil and gas industry. Bill Gates is an investor, as is his friend Jabe Blumenthal, a former Microsoft executive who is passionate about climate issues. So is N. Murray Edwards, an oil and gas billionaire. Keith, a physicist and climate scientist, has a joint appointment at the University of Calgary and at Harvard’s Kennedy School.
There’s no doubt that CO2 can be removed from the air using chemical processes. That’s how people can breathe on submarines or in spaceships. But the conventional wisdom among scientists is that it’s expensive and therefore impractical to do air capture on a global scale. Last year, a committee of the the American Physical Society produced a 100-page technology assessment, called Direct Air Capture of CO2 with Chemicals, which estimated that the cost of an air capture system would be “of the order of $600 or more per metric ton of CO2.” The report concluded: “Direct air capture is not currently an economically viable approach to mitigating climate change.”
Howard Herzog, an MIT professor, argues that it makes more sense to capture CO2 from the flue gas of power plants, where concentrations are higher — about 12 percent for coal plants or 4 percent for natural gas plants. (In the air, CO2 levels remain under 400 parts per million, which means that less than 0.04 percent of the air is CO2.) Herzog says anyone who claims that they can capture CO2 from the air at a low cost is “either not being totally honest or they’re deluding themselves.” He co-authored a peer-reviewed study in the Proceedings of the National Academy of Sciences that estimated the cost of air capture at “on the order of $1,000 per ton of CO2.”
“I am absolutely sure that’s wrong,” replies Carbon Engineering’s David Keith. In an FAQ on its website, Carbon Engineering offers a “conservative estimate” of the cost of air capture at “less than $250 per ton” of CO2 and says that it will drive costs lower. In his 1999 paper, Lackner estimated the cost of air capture as “on the order of $10 to $15 per ton,” a target that now appears wildly optimistic. This argument about about costs is crucial to the future of air capture, but it is unlikely to be settled until one of the startups begins to build industrial-scale plants.