Growth in enhanced oil recovery (EOR) projects using carbon dioxide (CO2) in West Texas could be limited by supplies unless new sources of the gas are found in the ground or from industrial facilities.
A recent report from the US Department of Energy (DOE) said that CO2 reserves currently supplying the region with a concentration of these projects have a 10- to 20-year life at current levels of demand, based on a price of USD 20 per bbl. at the source. This is, by far, the biggest concentration of fields where CO2 is used to add decades of production. The demand could go far higher in Texas based on the many other reservoirs that could benefit from it.
The report suggested, however, that this is not likely a hard limit on the carbon dioxide in the ground.
“The exploration for subsurface CO2 deposits is not well developed, as discovered CO2 deposits have generally been the byproduct of oil and gas exploration,” according to the report.
In contrast there is a lot of room for growth in the Northern Rockies, where 67% of the nation’s 96.4 Tcf of economically recoverable natural CO2 is found in the Big Piney-LaBarge Field, according to the report. While the formation is relatively deep, the high-pressure formations produce rapidly and also contain helium, a valuable commodity that can be sold to offset the cost of removing poisonous sulfur dioxide gas.
If oil prices rise enough to convince operators they can afford to pay more for the gas, the available reserve total will rise. The technically recoverable CO2 fields that could supply west Texas could supply the area for 30 years at current production rates.
The government agency is working to promote capture of industrial facilities to produce more oil using CO2 EOR, and cover the cost of injecting deep into the Earth the gas that can cause global warming. The next installment in the CO2 supply studies by DOE’s National Energy Technology Lab, covering the potential undiscovered sources of carbon dioxide, is expected soon. The US Geological Survey is also working on a more extensive evaluation.
Stephen Rassenfoss is the Emerging Technology Senior Editor for the Journal of Petroleum Technology.