UNIQUE GEOLOGY, UNIQUE OPPORTUNITIES CO2 SEQUESTRATION AND COMPRESSED AIR ENERGY STORAGE IN PNW BASALTS Casie Davidson, Senior Research Scientist Pacific Northwest National Laboratory Pacific Northwest Regional Economics Conference Portland, Oregon | 08 May 2014 PNNL-SA-102581 1 FLOOD BASALTS AS RESERVOIRCAPROCK SYSTEMS Dense Basalt Base of upper lava flow Sediment Vesicular Flow Top Dense Basalt STORAGE TARGET NOVEL COMPRESSED AIR ENERGY STORAGE PROJECT PACIFIC NORTHWEST NATIONAL LABORATORY B. Peter McGrail, Laboratory Fellow James Cabe, Research Scientist Casie Davidson, Research Scientist BONNEVILLE POWER ADMINISTRATION F. Steven Knudsen, Project Manager Ryan Redmond, Contract Specialist HIGH WINDS, HIGH RIVER FLOWS AND LOW LOAD RESULT IN ELECTRIC OVERSUPPLIES A SUITE OF POSSIBLE SOLUTIONS From Rahman et al. 2011, doi:10.1016/j.rser.2011.07.153 CAES FOR LARGE-SCALE WIND ENERGY STORAGE higher value peak electricity generation off-peak renewable electricity utilization SITING CAES IN PNW BASALTS HYBRID GEOTHERMAL CAES DESIGN • Yakima Minerals site lacks access to natural gas • Geothermal fluids from the sub-basalt sandstone can be used to replace conventional gas-fired processes at the surface: • During compression cycle, drive an ammonia chiller to provide cooling water for compressors • During generation cycle, reheat compressed air before passing it through a turboexpander to generate power TWO CANDIDATE SITES SELECTED FOR DETAILED STUDY COLUMBIA HILLS –Off the shelf technologies, only novel aspect is use of porous basalt, rather than large subsurface cavern –Dispatch as load in ~1 min; generation in < 10 min –Cost competitive with gas combustion and unsubsidized wind generation –Decreases emissions per MWh delivered to the grid relative to non-CAES gas plants YAKIMA MINERALS –Off the shelf technologies; novel pairing of CAES and geothermal –Dispatch as DEC in ~1 min; INC in < 10 min –Zero emissions from primary operation –Depths required result in higher costs than conventional CAES, but result in much higher storage density, smaller footprint, and larger DEC capacity –Could be competitive depending on revenue mix LEVELIZED COSTS OF ELECTRICITY (ASSUMED CAPACITY FACTORS IN PARENTHESES) BASALTS AS A CO2 STORAGE RESOURCE • Many of the same features that make basalts attractive for compressed air storage are appealing for CO2 storage as well • Mineralization leads to permanent storage of some portion of the CO2 as a solid • Proving basalts as a safe, effective storage reservoir for CO2 could present opportunities both in our region and around the world BASALTS ARE BY FAR THE LARGEST CO2 STORAGE RESOURCE FOR THE PNW WALLULA PILOT PROJECT • Big Sky Carbon Sequestration Partnership Phase II Demonstration • • • • • Final site selected in June 2008 Land Use Agreement signed August 2008 Drilling and characterization, Jan-May 2009 (TD 1222 m bgs) 1000 MtCO2 injection permit issued March 2011 977 MtCO2 injected between July 17 and August 11, 2013 • Currently working to update cost models with latest data from pilot • Characterization well used to update USGS basalt model 13 A BUSINESS CASE FOR CCS AT WALLULA 14 from McGrail et al., 2012. “Overcoming business model uncertainty in a carbon dioxide capture and sequestration project: Case study at the Boise White Paper Mill.” Intl J Greenhouse Gas Control 9 (2012) 91—102. KEY MESSAGES • Basalt-based CAES appears to be feasible and competitive with technologies currently used to supply balancing resources • Necessary technologies are commercially available as modular, scalable components • CAES has yet to be demonstrated in this class of storage reservoir • ROI / ROE will depend on pricing specifics (balancing, energy, arbitrage) • Basalts offer the highest capacity for CO2 sequestration in the Pacific Northwest • Unique chemistry offers the potential for more secure CO2 storage / lower risk • Basalts are costly to drill and monitor compared to sandstones, so in some cases offset purchase may be more appealing, but opportunities for lower-cost implementation exist