Is CCS (Geological Storage) Ready for Prime Time?

Stanford University Global Climate & Energy Project MIT Carbon Sequestration Forum VIII Stanford, November 11, 2007 Is CCS (Geological Storage) Ready for Prime Time? Sally M. Benson Energy Resources Engineering Dept., Stanford University Executive Director, Global Climate and Energy Project

Carbon Dioxide Capture and Geologic Storage Capture Compression Pipeline Transport Underground Injection

Options for Geological Storage Different types of formations have different states of readiness.

Key Elements of a Geological Storage Safety and Security Strategy With appropriate site selection informed by available subsurface information, a monitoring program to detect problems, a regulatory system, and the appropriate use of remediation methods IPCC, 2005 Financial Responsibility Regulatory Oversight Remediation the fraction retained is likely to exceed 99% over 1,000 years. risks similar to existing activities such as natural gas storage and EOR. IPCC, 2005 Monitoring Safe Operations Storage Engineering Site Characterization and Selection Fundamental Storage and Leakage Mechanisms

What Do We Need to Know? Financial Responsibility Regulatory Oversight Remediation Monitoring Safe Operations Storage Engineering Site Characterization and Selection Fundamental Storage and Leakage Mechanisms Financial mechanisms and institutional approaches for long term stewardship (e.g. monitoring and remediation if needed) Oversight for site characterization and selection, storage system operation, safety, monitoring and contingency plans Active and abandoned well repair, groundwater cleanup, and ecosystem restoration Monitoring plume migration, pressure monitoring in the storage reservoir and above the seal, and surface releases Well maintenance, conduct of operations, well-field monitoring and controls Number and location of injection wells, strategies to maximize capacity and accelerate trapping, and well completion design Site specific assessment of storage capacity, seal integrity, injectivity and brine migration Multi-phase flow, trapping mechanisms, geochemical interactions, geomechanics, and basin-scale hydrology

Is Geological Storage Ready for Prime Time? Financial Responsibility Oil and Gas Saline Aquifers Coalbeds Regulatory Oversight Remediation Monitoring Safe Operations Storage Engineering Site Characterization and Selection Fundamental Storage and Leakage Mechanisms

Are We Ready? State-of-the-art is well developed, scientific understanding is excellent and engineering methods are mature Sufficient knowledge is available but practical experience is lacking, economics may be sub-optimal, scientific understanding is good Demonstration projects are needed to advance the state-of-the art for commercial scale projects, scientific understanding is limited Pilot projects are needed to provide proof-of-concept, scientific understanding is immature New ideas and approaches are needed

Multi-phase Flow and Capillary Trapping Core Holder In Scanner High Pressure Pumps 38 mm 75 mm CO 2 Brine Differential Pressure Transducer Pressure Data Acquisition CO 2 Brine

Simulated CO2 Saturations Variable Pc Produces Small-scale CO2 Saturation Variations Lab Data Variable Φ, k Simulations Variable Pc Simulations 10% CO2 90% CO2 100% CO2 CO2 Saturation:0% 70%

Site Characterization: Frio I and Frio II Pilot Tests Injection well 30 m Observation well Δp (bar) 3 2.5 2 1.5 1 0.5 0 Injection Well Measured Calculated 0 200000 400000 600000 800000 1000000 Time (s) Frio Brine Pilot I Frio Brine Pilot II From S. Hovorka, UT Austin

Storage Engineering: Storage Capacity and Trapping Mechanisms Geological Model Computational Grid srl=0.6 Bottom Mid-depth Top Far from shale gap Near shale gap Original Low er Quarter Low er Half Full Upper Half Upper Quarter Mobile Dissolved Capillary Trapping 0 0.02 0.04 0.06 0.08 0.1 0.12 Reservoir Simulation Fractional Equivalent Pore Volume Storage Capacity and Trapping

Safety: TRC Rate for Oil and Gas Related Activities 20 10,00<employees <=31,600 31,600<employees <=100,000 100,000<employees <=316,200 316,200<employees <=1,000,000 18 16 TRC/200,000 hours/year 14 12 10 8 6 4 2 0 75% 50% 25% Geophysical Surveying and Mapping Services* Pipeline transportation of natural gas Drilling oil and gas wells Pipeline transportation Site preparation contractors Support activities for oil and gas ti * Oil and gas extraction Utility system construction *denotes industry class for which only 2004 rate available. Total Recordable Case (TRC) rate box plots for NAICS industry classes within an employment size group. Size groups shown are in thousands of employees. TRC rates for industry classes participating in the oil and gas exploration and production industry are shown.

Monitoring: ZERT Detection Verification Facility Detection Verification Facility (Montana State University) Flux Tower 80 m Field Site Horizontal Injection Well Hyperspectral Imaging of Vegetation Soil Gas Flow Controllers Flux accumulation chamber

Blowout Frequency and Management in District 4, California District 4, California 50,277 active wells 18,660 shut-in wells 36,940 abandoned wells Jordan and Benson, 2007, in preparation.

Regulations: Cradle to Grave Regulatory Framework Interstate Oil and Gas Regulatory Commission Seamless Simple Flexible and responsive Doable Storage of Carbon Dioxide in Geological Structures: A Legal and Regulatory Guide for States and Provinces. September, 2007. http://www.iogcc.state.ok.us/docs/meetingdocs/master-document-september- 252007-FINAL-(2).pdf

Quantitative Assessment of Long Term Liability and Risk Management Strategies Health Safety and Environmental Risk Pressure recovery Secondary trapping mechanisms Confidence in predictive models Injection begins Injection stops 2 x injection period 3 x injection period n x injection period Monitor Model Calibrate & Validate Models Calibrate & Validate Models

Conclusions Is CCS Ready for Prime Time? Oil and gas reservoirs: Yes Saline aquifers: Ready for commercial scale demonstration projects Coalbeds: Ready for pilot scale tests Readiness of storage safety and security strategy Operational safety Monitoring Fundamental science, remediation, and site selection Storage engineering, regulatory oversight Long term financial responsibility

Conclusions One persons opinion mine Engage scientific, engineering and regulatory community to assess state-ofthe-art Support deployment of demonstration projects now Identify high impact areas Fundamental and applied research Pilot projects