GE to develop enhanced sensing capabilities for underground CO2 storage wells

8 October 2012

GE Global Research signed a contract with the National Energy Technology Laboratory (NETL) to build a multi-point sensing system to monitor CO₂ injected into geothermal containment wells. The use of these cavities, which extend 1-2 kilometers below the surface of the Earth, is being explored by the federal government and power producers as an option for the long-term storage of CO₂.

Highly accurate monitoring, verification, and accounting are critically important to ensure that CO₂ pumped underground is confined to the potentially porous or fractured rock that contains each well. Currently, GE is testing a fiber optic cable with a sensor that can measure temperature and pressure at a single point inside the well. Readings from that pressure sensor have been calibrated to an accuracy of ±0.1%. This follow-up project would add a yet-to-be-determined number of additional sensors along the length of a multi-kilometer cable, enabling engineers to track the disbursement and movement of CO₂ within the sequestration well with even greater precision.

Our goal is to develop an incredibly resilient cable and sensor system that can withstand an extremely harsh environment for an extended period of time— temperatures as hot as 250 °C and pressures topping 10,000 psi. The work is very challenging. We have already developed a single sensor system that can tolerate temperatures as high as 374 °C and 3,000 psi for short periods. Now, we’ll leverage that knowledge to build a package that is even more robust and that can be multiplexed along the cable.

—Dr. William Challener, Principal Investigator and Physicist in the Photonics Lab at GE Global Research

Another key component of the project is wireless communication. GE scientists will develop a remote monitoring system capable of activating and operating the sensors from an off-site control room.

Work on the two-year, $1.2-million joint venture between GE Global Research and NETL is slated to get underway in January 2013.