Ongoing monitoring advances
will help operators achieve new levels of operational efficiency and risk
management to meet business objectives while providing local communities, regulators and investors with safe, durable
CO2 storage.
As industries worldwide continue to decarbonize their
operations on the way to net zero, the development of carbon storage, or sequestration,
is accelerating. According to the Global CCS Institute, the combined, announced
capacity of carbon capture and storage (CCS) projects in some stage of
development or construction has grown by more than 50% every year since 2020,
with an estimated 392 projects worldwide in the development pipeline, as of
July 2023.1
Designing, building, and cost-effectively managing these
projects requires a robust de-risking plan. Project de-risking is essential to ensuring
reliable, secure carbon dioxide (CO2) storage for the anticipated
20-to-30-year life of a project. It also ensures that the operator meets its
long-term business objectives, minimizes its operating expenses, and satisfies
the demands of several stakeholders:
Reducing storage risks with long-term monitoring,
measurement and verification. Detailed
evaluation of a potential carbon storage site is crucial to assessing its
long-term performance and viability to achieve the operator’s goals. Such
an evaluation provides a deeper understanding of the complexities of
identifying, analyzing and addressing the long-term requirements of carbon
storage sites.
Baker Hughes has developed a comprehensive monitoring,
measurement, and verification (MMV) planning process that helps operators address
the unique properties of every carbon sequestration project. The process includes
decades of application expertise in subsurface evaluation and modeling,
formation evaluation, integrated software solutions, and long-term monitoring
technologies. With this robust MMV offering, operators can proactively manage risks,
confirm well and reservoir integrity, reduce operating expenses (OPEX), satisfy
regulatory requirements, and optimize long-term project management.
The
MMV process leverages the industry’s widest range of advanced, passive
monitoring technologies to verify reservoir integrity and confirm that the
injected CO2 stays safely contained for the project's life. Application experts draw on
years of monitoring experience to select the optimal set of passive monitoring
systems for a given site’s injection and long-term storage requirements.
Experts begin the selection process at the prefeasibility
stage of project development, leveraging their knowledge to perform detailed assessments of storage performance,
evaluate the most cost-effective models for site injection, and ensure that the
MMV plan complies with geological storage regulations.
The
selection process includes a cost/benefit analysis to ensure that any proposed
monitoring technology delivers the most value for the project’s long-term
injection and monitoring goals while minimizing OPEX. This analysis helps the operator optimize the
design and installation of the project’s equipment and infrastructure—both in
the subsurface and at the surface. The MMV process also streamlines engineering iterations
to the final investment decision (FID), saving time and costs without
increasing risk or compromising safety.
The
site’s monitoring technologies are linked through a digital ecosystem designed
to handle the uncertainties, sensitivities, and nuances of CO2
storage analysis. During site operation, a digital integration platform
incorporates data from multiple monitoring sources—including logging tools,
fiber optics systems, and subsurface gauges—for a multi-faceted interpretation
of subsurface conditions and seismicity. Real-time data analytics and advanced
processing help detect low signal-to-noise ratio microseismic events and screen
out background noise. A digital traffic light warning system uses real-time
seismic data to provide both audible and visual warnings of a downhole event
exceeding predetermined conditions. The data sets are presented in a visual
format that allows the operator to respond to an alarm, make informed decisions
based on the current conditions, and take proper corrective action to mitigate any
risks.
This unique combination of real-time monitoring, OPEX
reduction, and digitally driven optimization has helped operators around the
world de-risk their MMV programs and ensure the long-term integrity of sequestration
projects.
Ensuring long-term storage integrity with permanent
monitoring arrays. An operator in southwestern France conducted a pilot
project to capture and store CO2 from an industrial power plant in
Lacq, with injection occurring near the town of Rousse and several kilometers
from an old gas field. A lithology survey of the area pinpointed a dolomitic
formation in the Rousse reservoir as a suitable site for the sequestration
pilot. The reservoir contained a horst bordered by normal faults and was
heavily depleted, which raised the risk of geomechanical instability.
The site was only 2 km (1.24 mi) away from the Meillon/Saint-Faust
fault and was in close proximity to population centers. Neighboring communities
voiced concerns about the pilot plant’s safety and its potential for creating
damaging seismic events. As a result, the regulatory authority charged with
approving the project closely scrutinized the permitting process and required the
operator to continually monitor reservoir seal integrity and seismic activity over
a six-year period.
The operator asked Baker Hughes to develop a reservoir
monitoring plan that satisfied regulatory requirements. The service company
simulated seismic source propagation to predict the optimal monitoring
configuration. The company also drew upon its decades of field execution
experience to select and install the optimal permanent seismic recording
equipment.
The proposed multi-scale monitoring solution included a regional
network of geophones installed at a depth of 4,400 m (14,436 ft) to monitor
reservoir and regional seismicity. The solution also included a highly
sensitive, shallow-buried geophone array installed at 200 m (656 ft) near the
injection site to monitor long-term injection processes. This combined solution
would allow the operator to simultaneously monitor caprock integrity and fault
reactivation for 30 years or more, with minimal operating costs.
The monitoring system provided real-time data to update and
refine the reservoir model. The data also afforded an early warning of any
events that may be associated with induced seismicity, enabling appropriate
mitigation measures to be implemented.
Prior to injection, the reservoir monitoring solution
characterized the natural seismicity of the reservoir and surrounding region. Documenting
the baseline seismic activity of the area gave the operator critical supporting
evidence to help discern between naturally occurring events and future
potential induced seismicity from injection operations.
Once the sequestration project commenced, the regional network
of deep geophone arrays detected seismic activity within the storage reservoir
during injection, but it confirmed that the caprock maintained integrity at all
times, Fig. 1. The network also confirmed that any seismic activity on
the pre-existing local fault was not caused by CO2 injection.
The consistency and reliability of the results allowed the operator to continue injecting CO2 in the culturally sensitive area with greater confidence. Over the six-year pilot period, the reservoir monitoring solution achieved the operator’s goals for proper risk management, community assurance, and injection volume while maintaining subsurface integrity.
Improving subsurface CO2
monitoring with autonomous stations advances. As the pace of CO2
sequestration project planning accelerates, Baker Hughes continues innovating to
lower the risks, costs and uncertainty of long-term CO2 monitoring. The
latest development, the CarbonWatch autonomous CO2 monitoring service,
combines an array of monitoring stations and field-proven sensors to capture a
wide range of field measurements—without an intervention operation and at 30%
lower OPEX than traditional measurement techniques.
Subsurface data are collected,
analyzed and mapped in near-real time to assure operators that their reservoirs
safely contain CO2 while conforming to regulatory requirements. By
providing continuous insights from the site’s existing digital ecosystem, the
service helps operators respond to anomalous monitoring measurements with
greater speed and accuracy.
Ultimately, ongoing monitoring advances
like this will help operators achieve new levels of operational efficiency and
risk management to meet their business objectives while providing local communities, regulators, and
investors with the peace of mind of safe and durable CO2 storage. WO
REFERENCE
OLE ENGELS is Baker Hughes's director for Energy Transition. As a global practice leader, his role includes subsurface applications in CO2 Sequestration, Geothermal, Hydrogen, and Energy Storage. He has over 25 years of experience in the energy industry. Mr. Engels’ background spans operations management, strategic planning, commercial and M&A, and technical and management consulting, with postings in Europe, the Middle East, and the U.S. He received an M.Sc. degree in geophysics and holds current advisory roles at Rice University and Texas A&M University.