How does EOR reduce CO₂ emissions? Using CO₂ captured from power plants and industrial sources to enhance oil production has the potential to help the U.S. reduce its emissions by improving the CO₂ intensity of the industrial and power generation sectors. Over the life of a project, for every 2.5 barrels of oil produced, it is estimated that EOR can safely prevent one metric ton of CO₂ from entering the atmosphere.3

A current estimate of CO₂ use for EOR is 72 million metric tons per year; 55 million metric ton of CO₂ come from natural sources and 17 million metric tons come from anthropogenic sources. But the potential for EOR to contribute to CO₂ reduction goals is great, as supplies of natural CO₂ are constrained. The volume that could be captured and sequestered from industrial facilities and power plants to support “next generation” EOR could be 20- 45 billion metric tons of CO₂. This is equal to the total U.S. CO₂ production from fossil fuel electricity generation for 10 to 20 years. (ARI, 2011)

Will CO₂-EOR harm groundwater resources? EOR is governed by federal regulations that require the protection of underground sources of drinking water, under the EPA’s Underground Injection Control (UIC) program. Many states have obtained authority from EPA to administer the UIC program and have laws that meet or exceed EPA’s requirements. Permits issued by the EPA or states require that EOR operators manage their site in a manner that will prevent CO₂ (and other formation fluids) from migrating out of the subsurface confining formation and into drinking water aquifers. ( 40 CFR §144.12)

The University of Texas Bureau of Economic Geology’s (TBEG) Gulf Coast Carbon Center has studied the longest running EOR site in the world at the Scurry Area Canyon Reef Operators in Scurry County, Texas (SACROC). SACROC has been operating since 1972 and has injected over 175 million tons of CO₂. TBEG has found no evidence that CO₂ has escaped the EOR site and contaminated groundwater resources. (TBEG)

Furthermore, the International Energy Agency’s Greenhouse Gas Programme (GHGP) Weyburn-Midale CO₂Monitoring and Storage project is the site of the world’s largest CO₂ monitoring project. Since 2000 more than 30 internationally recognized research organizations have conducted scientific assessments of the integrity of the geological storage system, monitored CO₂ in the deep subsurface, and tested for any evidence of anthropogenic CO₂ at the surface.None of the studies have detected anthropogenic CO₂ in the soils or groundwater. (Cenovus, 2011)

What is the land use impact? CO₂-EOR largely takes place at existing oil fields and CO₂ is transported through underground pipelines thus reducing land use impacts.

References:

• Advanced Resources International (ARI). (June 20, 2011). Improving Domestic Energy Security and Lowering CO2 Emissions with “Next Generation” CO₂-Enhanced Oil Recovery.
• 40 CFR §144.12
• See the SACROC Research Project website for a complete list of studies.
• Cenovus Energy, Site Assessment Weyburn Unit SW30-5- 13W2, November 2011.