Net energy returns from unconventional oil: Implications for the environment

Transcription

1 Net energy returns from unconventional oil: Implications for the environment Full pathway (point of use) net energy returns for pathways and industry [GJ/GJ] Jan70 National Geographic NER Mining POU NER In situ POU NER Mining & in situ POU Jan75 Jan80 Jan85 Jan90 Date Jan95 Jan00 Jan05 Jan10 New York Times Adam R. Brandt, Jacob Englander, Sharad Bharadwaj, Tim Yeskoo, Sco> McNally, Kourosh Vafi Contact: abrandt@stanford.edu GCEP Net Energy Analysis Workshop March 31st, 2015

2 Overview Transitions to unconventional hydrocarbons Empirical results for net energy returns from unconventional oil Implications for the environment 2

3 The oil transition Decades-long shift to unconventional hydrocarbon resources Traditional resources are mature and declining Increasing demand from developing nations High quality deposits less open for investment Unconventional resources are lower in quality Challenging reservoir: Tight formation challenges for shale oil Challenging resource: Upgrading and refining challenges for oil sands Challenging locations: Marginal or remote challenges for ultradeep, arctic 3

4 Unconventional resources growing rapidly Bitumen production from mining and in situ projects [m 3 /mo] 8 x Canadian oil sands Suncor Syncrude Mildred lake Syncrude Aurora Albian Sands Muskeg River mine Shell Scotford Shell Jackpine Williams Energy Inc. Imperial Kearl Lake OPTI Nexen Long Lake CNRL Horizon Shell Peace River Imperial Cold Lake Cenovus Christina Lake Cenovus Foster Creek Suncor Mackay River JCOS Hangingstone Suncor Firebag CNRL Primrose and Wolf Lake Total Joslyn Creek ConocoPhillips Surmont ConocoPhillips Surmont Pilot Nexen Long Lake Husky Tucker Lake Devon Jackfish 1 Shell Orion Connacher Great Divide Meg Christina Lake Statoil Leismer Baytex Cliffdale Pilot NPEC Red Earth Connacher Algar Eagle Ford (TX) Bakken (MT & ND) Spraberry (TX & NM Permian) Bonespring (TX & NM Permian) Wolfcamp (TX & NM Permian) Delaware (TX & NM Permian) Yeso-Glorieta (TX & NM Permian) Niobrara-Codell (CO, WY) Haynesville Utica (OH, PA & WV) Marcellus Woodford (OK) Granite Wash (OK & TX) Austin Chalk (LA & TX) Monterey (CA) US tight oil million barrels of oil per day Jan70 Jan80 Jan90 Jan00 Jan10 Date (Brandt, Bharadwaj et al. 2013) (Sieminski 2014) US tight oil: 4 million bbl/d (Sieminski 2014) Canadian oil sands: 2 million bbl/d (CAPP 2014) 4

5 What are the energy returns from extracting energy from unconventional oil? How do these energy returns compare to conventional oil resources? Should we be concerned about low energy returns from unconventional resources? If so, why? 5

6 How high can conventional oil go? The Lakeview gusher (1910) Midway-Sunset field 9-10 M bbl output Peak flow: kbbl/d Drilling energy Cable tool rig hp boilers, assume 50 hp Drilling for 15 months Energy payback time If drilling 24 hr/d for 15 months, energy payback was in 3-5 minutes of peak flow Gushed for 18 months Lakeview gusher, day 34. Source: Geo-Images Project, UC Berkeley NER of extraction: > 35,000:1 6

7 Trends in conventional oil over time Drilling productivity EROI EROI EROI Drilling million meters Drilling Intensity Year US oil EROI Drilling Intensity (Million Meters) Oil EROI Point of extraction energy return ratios! (NER/EROI and EER)! 140! 120! 100! 80! 60! 40! 20! NER/EROI (POE)! EER (POE)! California NER ! 1950! 1960! 1970! 1980! 1990! 2000! 2010! Year! Source: Hall and Cleveland (1981) Cleveland (2005), Guilford et al. (2011), Brandt (2011) 7

8 Is this story universal? Do we know if this general story applies to all unconventional oil resources? Two examples will show it does not: Oil sands mining has low energy returns but production is largely self-fueled Tight oil from Bakken (North Dakota) has high energy returns, but flaring confounds the story 8

9 Case 1: Canadian oil sands Oil sands are a challenging resource Energy intensive to extract Environmental impacts to water, air, and ecosystems Common net energy story Low energy returns from oil sands Resource is subsidized by cheap energy inputs (NG) Long- term viability is ques`onable National Geographic We performed detailed analysis 27 oil sands projects Monthly energy consump`on data from Brandt Brandt, Bharadwaj et al. (2013) 9

10 Oil sands process flow diagram Integrated mining and upgrading External energy inputs: Imported natural gas and electricity BITUMEN DEPOSIT Mining & Upgrading k m r s t u v NG Elec Elec NG H 2 Elec Steam Transport Refining Distribution SOCIETY Bitumen ore A B C D E F Refined fuels Coke Diesel Still gas Other n o p q Pet. coke Still gas Other w x y Diesel z Internal energy inputs: Coke and refinery gas residual fuels Brandt, Bharadwaj et al. (2013) 10

11 Oil sands net energy returns (synthetic crude oil) NER Mining Mine mouth NEER Mining Mine mouth Mine mouth energy returns for mining and in situ production [GJ/GJ] Include only external energy inputs: Energy returns = 20:1 to 40:1 Include all energy inputs: Energy returns = 5:1 0 Jan70 Jan75 Jan80 Jan85 Jan90 Jan95 Jan00 Jan05 Jan10 Date Brandt, Bharadwaj et al. (2013) 11

12 Case 2: Bakken GHG emissions and net energy study Conductor Surface casing Production casing TVD Turn Top Cond. bottom Surf. bottom Lateral top Prod. bottom Lateral casing Oil Prod. API # = , Hyper Results: EUR = e+05, b=0.010, D=0.012 S.E. Results: t = , n = 0.911, EUR = e+05 Well modeling: T. Yeskoo and K. Vafi ~7200 wells New model: GHGFrac DTD Lateral bottom Production modeling: S. McNally ~5300 wells Statistical tests of model fit Multi-year project funded by CARB, Argonne National Laboratory and CEIP Model results for 1000s of Bakken wells Use detailed engineering-based life cycle modeling with the Oil Production Greenhouse Gas Emissions Estimator (OPGEE)

13 Drilling + fracturing energy intensity for Bakken wells Drilling energy intensity (MMBtu/MMBtu crude EUR) Prod-weighted mean Median 95% 75% 25% How much energy does it take to drill and fracture a Bakken well? Full well information included (casing segment diameters, depths) Mud-pump, top-drive torque, cementing, fracturing via GHGFrac Jan-06 Jan-07 Jan-08 Jan-09 Jan-10 Jan-11 Jan-12 Jan-13 5% For 95% of Bakken wells, drilling and fracturing consumes less than 0.5% of lifetime crude output Brandt, Yeskoo et al. (2015); Vafi, Brandt (2015), McNally, Brandt (2015) 13

14 Bakken overall energy returns Bakken net energy ratio > 50 Brandt, Vafi, et al. (2015) About 2% of energy content of crude is consumed in producing and transporting Bakken crude, including embodied energy 14

15 But what about gas management in the Bakken? 3000 Flaring intensity (SCF/bbl, flaring wells only) % Prod-weighted mean Median 5% 0 Jan-06 Jan-07 Jan-08 Jan-09 Jan-10 Jan-11 Jan-12 Jan-13 How should flaring be counted in net energy studies? 95% 75% New York Times For flaring wells in 2013, ~14% of the equivalent energy content of crude was wasted in flares 15

16 A bounty of unconventional oil Trillions of barrels of unconventional oil Canadian oil sands: ~ 2 Tbbl in place (Speight 2007) Venezuelan extra-heavy: ~ 1 Tbbl in place (Speight 2007) Tight oil (shale): 0.4 Tbbl tech. recoverable (EIA 2013) Byproduct or self-fueled processes can allow extraction with high effective external energy returns Low energy efficiency need not limit supply Energy and GHG intensive processes can be used if economic Current processes are likely scalable for decades Disregarding energy returns, what are implications of burning this carbon? 16

17 Summary Will low energy returns limit our ability to extract unconventional oil resources? No: Energy returns unlikely to present fundamental limit to extracting oil sands and tight oil resources for some time Are low energy returns (broadly defined) important? Yes: Environmental impacts scale with total energy consumption Are we paying sufficient attention to environmental implications? No: Environmental management challenged by resource quality and location No: Not enough attention on implications of very large resource base 17