Calera is a company funded by Vinod Khosla which is trying to make concrete that pulls carbon dioxide from the air instead of emitting it. This would have a huge reduction in greenhouse gases when fully deployed. Concrete manufacturing is a primary source of carbon dioxide.
For each ton of Calera concrete one ton of carbon dioxide is removed from the air. Calera is completing a pilot plant by the end of 2008. They plan to complete a commercial plant by 2010 and have 100 sites within 5 years.
Constructing and operating buildings requires 48% of the energy used in the United States. 21% for residential buildings. 27% for transportation and 25% for industrial.
Cement is a huge culprit of greenhouse gas emissions: It uses about 2.5 billion tons of cement a year, and produces that many tons in carbon dioxide.
There are many green building companies being funded
New Jersey-based Hycrete, which produces an admixture (or liquid solution) that is used to waterproof concrete, completed its second round in 2006. Hycrete makes a mixture of sand, aggregate, cement and water, the admixture acts as a replacement for the external membranes that are typically used to keep water from seeping into concrete. When it is mixed into concrete, it links up to metallic ions and behaves like a hydrophobic solution (like oil) — repelling water. Because it doesn’t require volatile organic compounds (VOCs) or other harmful chemicals, the corrosion-resistant concrete can safely be recycled and reused in other projects.