A couple of climate tech startups plan to suck a hell of a lot of carbon dioxide out of the air and trap it underground in Wyoming. The Verge reports: The goal of the new endeavor, called Project Bison, is to build a new facility capable of drawing down 5 million metric tons of carbon dioxide annually by 2030. The CO2 can then be stored deep within the Earth, keeping it out of the atmosphere, where it would have continued to heat up the planet. A Los Angeles-based company called CarbonCapture is building the facility, called a direct air capture (DAC) plant, that is expected to start operations as early as next year. It’ll start small and work up to 5 million metric tons a year. If all goes smoothly by 2030, the operation will be orders of magnitude larger than existing direct air capture projects.
CarbonCapture’s equipment is modular, which is what the company says makes the technology easy to scale up. The plant itself will be made of modules that look like stacks of shipping containers with vents that air passes through. At first, the modules used for Project Bison will be made at CarbonCapture’s headquarters in Los Angeles. In the first phase of the project, expected to be completed next year, around 25 modules will be deployed in Wyoming. Those modules will collectively have the capacity to remove about 12,000 tons of CO2 a year from the air. The plan is to deploy more modules in Wyoming over time and potentially manufacture the modules there one day, too.
Inside each of the 40-foot modules are about 16 “reactors” with “sorbent cartridges” that essentially act as filters that attract CO2. The filters capture about 75 percent of the CO2 from the air that passes over them. Within about 30 to 40 minutes, the filters have absorbed all the CO2 they can. Once the filters are fully saturated, the reactor goes offline so that the filters can be heated up to separate out the CO2. There are many reactors within one module, each running at its own pace so that they’re constantly collecting CO2. Together, they generate concentrated streams of CO2 that can then be compressed and sent straight to underground wells for storage. DAC is still very expensive — it can cost upwards of $600 to capture a ton of carbon dioxide. That figure is expected to come down with time as the technology advances. But for now, it takes a lot of energy to run DAC plants, which contributes to the big price tag. The filters need to reach around 85 degrees Celsius (185 degrees Fahrenheit) for a few minutes, and getting to those kinds of high temperature for DAC plants can get pretty energy-intensive. Eventually, […] Bison plans to get enough power from new wind and solar installations. When the project is running at its full capacity in 2030, it’s expected to use the equivalent of about 2GW of solar energy per year. For comparison, about 3 million photovoltaic panels together generate a gigawatt of solar energy, according to the Department of Energy. But initially, the energy used by Project Bison might have to come from natural gas, according to Corless. So Bison would first need to capture enough CO2 to cancel out the amount of emissions it generates by burning through that gas before it can go on to reduce the amount of CO2 in the atmosphere. “The geology in Wyoming allows Project Bison to store the captured CO2 on-site near the modules,” adds The Verge. “Project Bison plans to permanently store the CO2 it captures underground. Specifically, project leaders are looking at stowing it 12,000 feet underground in ‘saline aquifers’ — areas of rock that are saturated with salt water.”