
Boundary Dam, Saskatchewan, Canada —
Boundary Dam Carbon Capture and Storage Project in Estevan, Saskatchewan, captures approximately one million tons of CO2 per year according to the Global Carbon Capture and Storage Institute (GCCSI). The Canadian facility uses CO2 in enhanced oil recovery, a process where gas is injected underground to flush out residual oil from rock formations between oil wells.

Sleipner gas fields, North Sea —
Sleipner gas platform, 155 miles off the coast of Norway. Its carbon storage facility captures and injects carbon dioxide deep under the North Sea into a sandstone reservoir. StatoilHydro, who operate the rig, has sequestered 16 million metric tons of CO2 since 1996, say the company.

Petra Nova Carbon Capture Project, Texas —
Coal mounds NRG Energy Inc. WA Parish generating station in Thompsons, Texas. The plant, home to the Petra Nova Carbon Capture Project, injects 1.6 million metric tons of CO2 every year in its enhanced oil recovery operation -- equivalent to 90% of its CO2 emissions, say NRG. It's the largest project of its kind in terms of capture volume currently operating in the US, per the GCCSI.

Hellisheidi Geothermal Power Plant, Iceland —
Hellisheidi Geothermal Power Plant outside Reykjavik, Iceland. Carbon dioxide emissions from the plant are dissolved in water and re-injected into basaltic bedrock and locked in mineral form. Reykjavik Energy's CarbFix2 program aims to make the site carbon neutral, and at present 60% of gases are now turned into minerals underground, with the long-term objective to make the site's operation "traceless" in terms of gas emissions.

Illinois Industrial Carbon Capture and Storage, Illinois —
In Decatur, Illinois, the Archer-Daniels-Midland Co. plant processes corn and turns it into ethanol. The factory produces 350 million gallons of ethanol each year, and in 2017 announced it plans to inject approximately 1.1 million metric tons of CO2 per annum emitted during manufacture into a nearby saline aquifer 7,000 feet underground.
Quest Carbon Capture and Storage, Alberta, Canada —
Quest's hydrogen production plant outside Edmonton launched its CCS initiative in November 2015, transporting captured CO2 to a separate site for geological storage. Shell, who operate the site, reported it had stored its first 2 million metric tons ahead of schedule, and also made the argument that if they built the site again, it would cost 20-30% percent less to construct and operate.

