GCEP RESEARCH SYMPOSIUM 2012 STANFORD, CA. Sally M. Benson. Director, Global Climate and Energy Project Stanford University OCTOBER 10, 2012

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1 May 15-16, 2013 Research at Stanford University in: Carbon Mitigation and Advanced Combustion GCEP RESEARCH SYMPOSIUM 2012 STANFORD, CA Sally M. Benson Director, Global Climate and Energy Project Stanford University Lynn Orr Stanford University OCTOBER 10, 2012 GLOBAL CHALLENGES GLOBAL SOLUTIONS GLOBAL OPPORTUNITIES

2 Global Exergy Stores Exergy (ZJ) Geothermal Energy* Deuterium tritium (from Li) Uranium Thorium Coal Gas Hydrates Oil Gas Yearly Human Consumption From Hermann, 2006: Quantifying Global Exergy Resources, Energy 31 (2006)

3 Reducing CO 2 Emissions from Fossil Fuel Use Improve combustion efficiency Capture and store some of the CO 2 in the subsurface Switch fuels to lower carbon content (coal to CH 4 for electric power generation, for example) Average Conversion Efficiencies Nuclear 30% Coal 30-40% Natural Gas 40-60% Wind 50% Solar 15% Source: US EIA,

4 Conversion Efficiency of Engines First-Law Efficiency (%) % Time (Years A.D.) Savery, Newcomen (<0.5%) Watt/Boulton Steam Engines Post-Watt Steam Engines Lenoir, Hugon Coal-Gas Engines Otto/Langen Coal-Gas Engines Atkinson, Tangye Coal-Gas Engines Banki Spirits Engine Priestman's Oil Engine Diesel's Oil Engines Automotive SI Engines Truck Diesel Engines Large Bore DI Diesels Steam Turbines Gas Turbine/Steam Turbine Polymer Electrolyte Membrane FC Phosphoric Acid Fuel Cells SOFC/Gas Turbine Source: C. Edwards, GCEP

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8 Advanced Coal Conversion - Supercritical Water Oxidation with CCS Reginald Mitchell and Chris Edwards, Stanford University Analysis of full SCWO system shows overall efficiency of 37% and is a potential option for the efficient use of coal in electricity generation with zero emissions to the atmosphere.

9 Enhanced Oil Recovery by CO 2 Injection If pressure is high enough, oil is displaced very efficiently in the swept zone. Transfer of components between phases by phase equilibrium and chromatography is responsible.

10 Reservoir Displacement Heterogeneity and gravity strongly influence well-to-well flow of injected gas. Extremes of permeability dominate the flow. Low viscosity CO 2 will find the easy flow paths between wells. Breakthrough of injected CO 2 limits sweep efficiency and recovery. Stanford has performed decades of research to delineate the physical mechanisms and model accurately the fluid flows in heterogeneous subsurface reservoirs

11 Example: CO 2 Storage in a Gas Reservoir containing Condensate Gas Saturation Total Mobility Numerical dispersion prevents finitedifference methods from resolving the condensate bank, except at very high grid resolution, even in 1D. Wave Velocity (z/t) 13 component fluid description (35% H 2 S), pure CO 2 injection ln(k) Heterogeneous permeability field, = 13,500 grid blocks

12 S gas after 2500 Days Injection Compositional Streamlines 24 seconds CSLS approach is 1600 times faster than FD (and the speedup scales as the number of grid blocks squared). S gas For large-scale compositional simulations sensitive to numerical dispersion, CSLS is the only feasible approach. Finite difference 38,991 seconds ERE CCS Faculty: Benson, Brandt, Kovscek, Tchelepi, Wilcox

13 Substituting Natural Gas for Coal in Electric Power Generation Reduced SOx, NOx, particulate, Hg emissions Reduced mining impacts, ash disposal Reduced CO 2 emissions per kwh generated: 57% less CO 2 per unit energy in fuel for natural gas Better power plant efficiency 32% old coal 35% NG single cycle 60% NG combined cycle CO 2 /kwh reductions: NG 48%, NGCC 70% (if no leakage of CH 4 ) Source: sizes/l/in/photostream/ Source:

14 Global Shale Plays Major Reassessments Reported In England, Argentina and Bengal Province ~22,600 TCF of Recoverable Reserves 6600 TCF from Shale (40%) Current use ~160 TCF/year 14

15 Shale Gas Basins and Gas Pipelines, India & Pakistan Source: US EIA, World Shale Gas Resources (ARI)

16 Shale Gas Research Questions Adsorption, diffusion, and flow in nanoporous shales Fracture properties, slow slip CO 2 adsorption, possible CH 4 stimulation Accurate long-term shale production modeling at field scale Gas firming of intermittent renewables Faculty: Brandt Wilcox Zoback

17 Conclusions Remaining fossil fuel resources are quite large: reducing worldwide GHG emissions will require using them in very different ways in the future Substituting natural gas for coal in electric power generation reduces CO 2 emissions and has many other benefits (air quality, health, mining, ) Shale gas: potential for significant additional supplies worldwide, many remaining research questions Capturing and storing CO 2 in the subsurface can contribute significantly to emissions reductions. Enhanced oil recovery is the primary initial target for economic reasons

18 Stanford Energy Research earth image source NASA 18