In January 1972 the Val Verde (now Terrell) natural gas process plant started to capture carbon dioxide (CO2, or, short, “carbon”) and transport it in a pipeline to the Kelly Snyder oil field in West Texas. It was the first commercial use of CO2 for enhanced oil recovery (EOR). EOR had been slow in the making. The first patent for EOR was issued in 1952 and field test had been done in 1964, but in the last three decades EOR has become a well-established technology in the North American oil industry. Most of the CO2 comes from naturally occurring sources.

CO2 is the main anthropogenic (human induced) greenhouse gas (GHG), about 76 %. Consequently, it is the focus when addressing global warming.