Carbon Capture: Possible Solutions, Pt. I

How Much Needs to Be Stored?
Lots, and it needs to be stored for thousands of years. The UN Intergovernmental Panel on Global Change (IPCC) estimates that 10 percent to 50 percent of the emissions reductions goals for 2100 could come from CCS. Humans emit about 27 gigatons of CO2 every year.

There are, of course, risks. The companies that today would pump the CO2 in the ground may very well cease to exist in a few hundred years. According to the IPCC, it's very probable that 99 percent of the stored CO2 would remain stored within the first 100 years after injection. But the question about global responsibilities and carbon taxes is yet to be solved.

The Coal Utilization Research Council (CURC) notes that there is a portfolio of options and different coals may require different solutions. They also emphasize that retrofit solutions will be more costly than new plant solutions due to space limitations, and relatively low initial power plant efficiencies.

Locations
There are three different locations where CO2 could be stored: oil and gas reservoirs, deep saline formations, and coal beds that can't be mined. In each case, CO2 is stored by injecting it in dense form into rock formations below the surface of the earth. This method is already used in the oil and gas exploration and production industry for, among others, enhanced oil recovery. And the technology for exploring oil and gas reservoirs today could be used for finding storage sites for CO2 in the future.

The possibility of injecting CO2 in geological formations such as basalts, oil and gas shales, salt caverns and abandoned mines are all seen as niche opportunities to this day and would need more research to investigate their potential.

Diagram of a CO2 Storage Facility

_{Source: Vattenfall}

Continue to Part II: Carbon Economics.