The Los Gatos startup that pledged to turn greenhouse gas into cement has landed its first job: a sidewalk in the
city of Santa Cruz.
While a relatively small project, the 400-foot walkway off Morrissey Boulevard will serve as a big test for plans
by the environmentally-minded Calera Corporation to capture carbon dioxide exhaust from the Moss Landing
Power Plant and fashion it into commercially viable construction materials, like cement.
"We're at the point where we want to start using our materials in the built-in environment," said Martin
Devenney, vice president of materials development at Calera. "It's part of the process of getting your material
accepted in the concrete industry."
City officials won't be the only ones watching what the company can do. So too will local and state transportation
managers who have control over lucrative construction contracts and may be partial to using a cement that
helps in the fight against global warming for future road projects.
"This is the way to bringing it forward," said Kim Shultz, Highway 1 project manager for the Santa Cruz County
Regional Transportation Commission.
The Regional Transportation Commission coordinated the sidewalk deal with Calera in hopes of bringing Calera's
environmentally superior cement to other projects, like Highway 1 widening.
For three years, Calera has been testing its technology at a plant in Moss Landing, making small batches of
cement there. In the process, it's lured tens of millions of dollars of investment to its Los Gatos research facilities,
including $20 million of federal stimulus funds this summer, all going toward scaling up operations.
Devenney says the cement being produced now looks and feels like the industry-standard Portland cement. It
comes with the advantage, though, of getting almost half its mass from sequestered carbon dioxide, according
to Calera. Portland cement, when made, spews out carbon dioxide - often ton for ton.
"When you can replace any percentage of normal cement (with our cement), that's highly advantageous,"
Devenney said.
Calera representatives are hesitant, at this point, to disclose exactly how much carbon dioxide the process
captures, or even if there is a net loss of the greenhouse gas. The company, though, is firm that as it ramps up
production and the technology is perfected, the cement will be carbon negative.
The Calera process works by allowing carbon dioxide from the power plant to be absorbed into seawater, which
gives rise to solid mineral carbonates and bicarbonates that can be spray-dried into cement, according to the
company.
Santa Cruz officials remain cautiously optimistic about using the new cement.
"We're going to try it. We've never done it before, but I don't see any downside," said the city's Public Works
Director Marc Dettle.
The new sidewalk will run along Rooney Street at the junction of Morrissey Boulevard. Conventional cement will
also be part of the blend, though how much Calera cement is used versus ordinary cement is yet to be
determined.
A contractor to build the sidewalk has not yet been selected.
The work is part of the $15 million expansion of Highway 1 between Morrissey Boulevard and Soquel Drive and the rebuild of the La
Fonda Avenue overpass, slated to begin next summer. The sidewalk, which is adjacent to the freeway, is expected to be among the first
projects done.
(转自Santa Cruz Sentinel (Calif.))