Carbon management for energy and climate security

Transcription

1 Carbon management for energy and climate security Jane C. S. Long Julio Friedmann Lawrence Livermore National Laboratory, P. O. Box 808, Livermore, CA This work was performed under the auspices of the U.S. Department of Energy by the University of California Lawrence Livermore National Laboratory under Contract No. W-7405-Eng-48.

2 Key Point 1: We know enough today to execute a CCS project for a specific site at scale CCS is a known technology We know how to do the following things well Select and characterize a site Operate a large-scale injection at that site Deploy a monitoring array Asses hazards at that site Mitigate and remediate potential leaks Plug and abandon wells post-injection

3 Carbon dioxide can be stored in deep geological formations as a dense, pore-filling fluid Saline Formations: Largest capacity (>2200 Gt) Depleted Oil and Gas fields: Potential for enhanced oil and natural gas recovery Un-mineable Coal Seams: Potential for enhanced gas recovery Scientific American, 2005

4 Site selection due diligence requires characterization and validation of ICE Injectivity Capacity Effectiveness Injectivity Rate of volume injection Must be sustainable (test for months use for years) Capacity Bulk (integrated) property Total volume estimate Sensitive to trapping mechanisms Effectiveness Ability for a site to store CO 2 Long beyond the lifetime of the project Most difficult to define or defend Without ICE, you don t have a project Gasda et. al, 2005

5 Storage mechanisms (safety issues) are reasonably well understood Physical trapping Impermeable cap rock Up to 100% Residual phase trapping Capillary forces immobilized fluids Sensitive to pore geometry geometry (<25% pore vol.) Solution/Mineral Trapping Slow kinetics High permanence1-4% Gas adsorption For organic minerals only (coals, oil shales) 1.0 MgCO NaAlCO 3 (OH) 2

6 Key Point 2: We don t know enough today to execute CCS at scale nation-wide or world-wide Uncertainties remain on technical issues that will affect regulations and the development of standards Resource distribution Monitoring and verification for accounting Acceptable risk profile Site closure requirements Far-field effects (e.g., water displacement) These concerns arrise because of the SCALE of CCS that is being contemplated

7 National assessments of sequestration resource have begun, but require more work DOE Atlas Preliminary, quantitative estimate Built by regional partnership efforts Some individual formations Estimates conform to earlier, less rigorous calc. (IEA 2004; Dooley & Friedmann, 2004) More work would be useful Resource density distribution Preliminary screening by risk Capacity estimate methodology NETL, 2007

8 Developing an accepted methodology for monitoring and verification of CO2 injections There are an abundance of potential methods and tools This is a major component of the DOE/NETL research program Monitoring for site characterization programs should (1) be minimal (2) define and improve understanding of local geology and geography (3) aimed at constraining effectiveness Development of monitoring standards will greatly affect the regulatory framework But This is difficult because every site is different Socolow, 2005

9 There is no accepted methodology to quantify risks or assess hazards from sequestration Uncertainties persist in key aspects: What are proper abandonment protocols? When does monitoring cease? When does liability transfer to a new party? Are there unanticipated long-term concerns? What are the real magnitudes of these risks? Conceptual Risk Profile These uncertainties impede commitment of capitol to operational projects today Courtesy S. Benson, Stanford

10 Key point 3: The true scope of large-scale CCS deployment is the primary challenge and source for concerns The scope and scale of injection from a single coal plant must be considered. One 1000 MW plant: 6 MM t CO 2 / yr 120, ,000 bbl/d After 60 year, G bbls CO 2 plume at 10y, ~10 km radius: at 50 yrs, ~30 km radius >100 wells Need large scale injection pilot tests to understand scale effects for this magnitude of injection

11 Magnitude of the problem To sequester 100% of US coal emissions today: Volume at depth = 33 million barrels/day; Equal to ~1/3 of daily global oil produced After 50 years Reservoir volume required = 500 billion barrels Equals 50% of historical oil production world-wide

12 There appears to be enough global sequestration resource to sequester 2 Gt C/yr (7 Gt CO 2 ) indefinitely More than enough accessible rock volume for sequestration Large capacity exists in US, Canada, other OECD countries Appears viable in most of world, including India and China Injection rate is the limiting factor, not capacity. High-quality easy storage will be used first, with lower grade rock volumes used later. Site-specific, economic estimates Global, total volume estimates Highest value, early sites

13 How the current costs may change due to scale-up issues is unknown Today, CCS is the least expensive way to de-carbonize electricity Main cost is capture Assessment is the cheapest, most critical step With scale up Capture costs likely to decrease Storage costs may go up: Best storage sites used first, following sites are more expensive (e.g. lower injectivity) Good storage sites not co-located with power plants Land access, materials, and infrastructure become issues

14 Concluding remarks CCS is the best and most important example of a technology we largely know, have used and can do but are not doing at the scale that can have a major impact on carbon emissions from electricity generation CCS buys time The U.S. should move aggressively on a CCS program now We can have the information we need to commence a major injection program most likely within a decade

15 Extra material

16 Year 2005 U.S. Energy Flows 100 quadrillion Btu per year US energy: 100 Quads

17 Year 2005 CO 2 6 GtCO 2 per year

18 CCS is cost competitive and the potential to solve half the problem Cost for CO 2 avoidance ($/ton CO 2 ) Coal to coal Coal to gas Late change coal IGCC w/ CO 2 capture Oil to gas Pulverized coal w/ CO 2 capture Reforestation Natural Gas CC w/ CO 2 capture Solar PV Nuclear Wind fission Hydro Biofuels CO 2 capture w/ EOR/ECMB Potential CO 2 abatement (%) Adapted from Lars Stromberg, Vattenfall AB, Electricity Generation, Sweden, 2001; SPA Pacific

19 Site selection requires Injectivity A 500 megawatt IGCC plant will produce 3 MM tons of CO 2 each year. Injectivity must match that load. Estimated in many ways Permeability tests of core Stem, injection, production tests Stratigraphic connectivity A Dolomite A Sandstone B Dolomite B Sandstone C Dolomite Stratigraphy (local & regional) Ultimately a function of difficult to predict or measure key terms Pore throat diameter (local) Cap rock yield strength Relative permeability Ultimately, can be engineered Increased injection length (deviated wells) Stimulation (hydrofracture) Oil Water Socolow, 2005

20 Site selection requires Capacity A 500 megawatt IGCC plant will produce 180 MM tons of CO 2 in 60 years. Capacity must match that volume. Estimation requires pore volume estimates: conventional mapping & conventional tools Unit thickness and extent (rock volume) Net:gross (sand percent) Porosity/effective porosity Ultimately a function of pore-scale process over functional injection duration and area Physical trapping; saturation Conventional simulation to define extent of plume relative to rock volume The rest (residual, dissolved, mineralized fractions) While the rest may be difficult to estimate precisely, reasonable estimation can be done with conventional tools

21 Site selection requires Effectiveness Emissions from a 500 megawatt IGCC plant should reside in the crust a long time for CO 2 storage to be effective Initial characterization is simple Does it close? (structurally, stratigraphically, hydrodynamically? Is there one of more good seals? Are there high permeability conduits out that will leak Friedmann & Stamp, in press Multiple initial screening tools, multiple supporting tools Geological mapping, characterization and correlation Capillary entry pressure Stress tensor estimation Harrington & Horseman, 1999

22 Accurate determination of the resource is a priority Current resource assessments of capacity vary by three orders of magnitude. Study Location World - Koide 92 World - van der M eer 92 World - IEA 92 World - Hendriks and Blok 93 World - Hendriks and Blok 94 World - IEA 94 World - Hendriks 94 World - Hendriks & Blok 95 World - Turkenburg 97 World - IP CC 01/Arc 00 World - ECOFYS & TNO-NITG 2002 World - Bruant 02 World 1 - GEOSEQ World 2 - Beecy & Kuuskra 01 World 3 - IEA World - Dooley and Friedman World - ECOFYS Europe - van der Straaten Europe - Boe et al NW Europe - Joule Report Western Europe - Dooley amd Friedman Eastern Europe - Dooley and Friedman Former Soviet Union - Dooley and Combined Europe - Dooley and Friedman Western Europe - ECOFYS Eastern Europe - ECOFYS Total Europe - ECOFYS USA - Bergman & Winter (M t Simon Sandstone (Ohio (M t Simon Sandstone (M idwest USA M t Simon Sandstone USA - Dooley and Friedman USA - ECOFYS Alberta Basin (Canada) - Total Alberta Basin (Canada) - Viking Fmn Canada - Dooley and Friedman Canada - ECOFYS Australia - Bradshaw et al 2002 Australia/NZ - Dooley and Friedman Oceania - ECOFYS Japan - ECOFYS Japan - Dooley and Friedman Japan World : ,000 GT Europe : GT USA : GT Canada : GT Australia : GT Japan : 0 80 GT 1 10 Carbon Sequestration Leadership Forum, ,000 GT CO 2 10, ,000 1,000,000

23 Leakage risks remain a primary concern 1) High CO 2 concentrations (>15,000 ppm) in air can harm environment and human health 2) Potential risks to groundwater, environment 3) Economic risks flow from uncertainty in subsurface, liability, and regulations

24 The focus for operational protocols should be HAZARDS first, RISKS second HAZARDS are easily mapped & understood, providing a concrete basis for action RISK = Probability * consequence RISKS are often difficult to determine Hard to get probability or consequence from first principles Current dearth of large, well-studied projects prevents empirical constraint

25 Sources for risk analysis Analog information abundant Oil-gas exploration and production Natural gas storage Acid gas disposal Hazardous waste programs Natural and engineered analogs Operational risks No greater than (probably less than) oil-gas equivalents Long experience with tools and methodologies Leakage risks Choose site well Fluxes likely to be small Mitigation techniques exist Bogen et al., 2006

26 Potential injection sites match emission source locations fairly well Many pure CO 2 streams currently exist in highly prospective areas Bradshaw et al., 2004