Startup says it can trap carbon dioxide emissions in cement
(Moss Landing, California) -- It seems like alchemy: a Silicon Valley startup says that it has found a way to capture the carbon dioxide emissions from coal and gas power plants and lock them into cement.
If it works on a mass scale, the company, Calera, could turn that carbon into gold.
Cement production is a large source of carbon emissions in the US, and coal-fired electricity plants are the biggest source. As nations around the world press companies to curb greenhouse gas emissions, a technology that makes it profitable to do so could be very popular. Indeed, Calera's marketing materials may be one of the rare places where glowing quotes from a coal company and the Sierra Club appear together.
'With this technology, coal can be cleaner than solar and wind, because they can only be carbon neutral,' said Vinod Khosla, the Silicon Valley billionaire. His venture capital firm, Khosla Ventures, has invested about US$50 million in Calera. On Monday, Calera is set to announce that Peabody Energy, the world's biggest coal company, has invested US$15 million.
Although Calera has a pilot project up and running, it is still not clear that the process can be used on a large scale or that anyone will buy the cement it makes.
Some climate scientists and cement specialists are dubious that Calera can produce large quantities of cement that is durable and benign for the environment.
'People have been looking for ways to do this for 15 years,' said Ken Caldeira, a specialist on the carbon cycle who is a senior scientist with the Carnegie Institution for Science at Stanford. 'The idea that they're going to come up with something that's both economic and scalable? I'm highly sceptical.'
Major carbon emitters and green technology companies have been trying to figure out ways to capture and store carbon, such as injecting it into the ground, in case Congress begins to regulate carbon emissions.
Calera says that by turning carbon into a building material, it will make carbon reduction economically attractive even in places where there are no government subsidies or carbon taxes. 'In this case, it's actually a profit centre,' said Brent Constantz, Calera's founder and chief executive.
Mr Constantz, who is a consulting professor at the Stanford School of Earth Sciences, has spent his career studying and creating different kinds of cement. As a graduate student, he studied how corals in the Caribbean use carbon dioxide to make their skeletons. He started two companies, Norian and Skeletal Kinetics, that make a calcium phosphate cement that surgeons use to repair broken bones.
In 2007, he and Mr Khosla hatched plans for Calera. Today, Mr Khosla is effectively part of the management team, involving himself in details and speaking with Calera executives daily.