To make the CO2 bricks, Belcher and her graduate students modified baker's yeast to express genes that are normally found in sea creatures like abalones, which make hard carbonate shells. Carbon dioxide is bubbled into water, and then combined with mineral ions to make solid carbonate materials. Enzymes in the yeast help the mineralization process.New Process Uses Genetically Modified Yeast to Turn Carbon Dioxide Emissions Into Bricks for Construction
The process can produce two pounds of carbonate for every pound of captured CO2, according to MIT.
Let's see... we need to pull ~32 gigatonnes per year out of the atmosphere to remain at ~390 ppm... that's 70400000000000 pounds of bricks a year, providing we continue emissions at today's rate.