Trends in Carbon Intensity of Ethanol vs. Petroleum

Transcription

1 Trends in Carbon Intensity of Ethanol vs. Petroleum Presented by: Steffen Mueller, PhD Principal Research Economist and Stefan Unnasch Managing Director, Life Cycle Associates Presented at: Energy Future Coalition, Washington DC May 2014

2 Presentation Overview Where is the Carbon Intensity of the Petroleum Mix Going Where is the Carbon Intensity of Corn Ethanol/Biofuels Going Issues with RFS2 GHG Analysis

3 Petroleum Baseline Since RFS2 Implementation In response to rising demand, there has been a fundamental shift in U.S. oil production towards unconventional/marginal resources (tight oil). Tight oil is liquid oil stored in micropores of shale formations; fracking is used to break up the oil laden microporous rock by injecting high pressure liquid into the rock bed. Recent advances are now making the extraction of unconventional oil technologically possible and economically viable at current oil prices. The amount of recoverable oil from one of the largest U.S. reserves, the Bakken Reserve in North Dakota and Montana has increased 25 fold (an additional 3 to 4.3 billion barrels of oil) from early estimates, becoming the largest oil accumulation in the lower 48 states and accounting for 7% of the total U.S. onshore oil production. Bakken oil is produced with a high gas-to-oil ratio (380 scf/bbl)

4 Bakken: Night time Flaring Source: Sklar, J. (2013) Gas flares from Bakken fracking are visible from space. New Scientist. January 2013:

5 Petroleum Baseline: U.S. domestic crude production by source Note: US Production Accounts for ~40% of US Consumption Source: Susan Boland, Stefan Unnasch; Carbon Intensity of Marginal Petroleum and Corn Ethanol Fuels ; Life Cycle Associates, 2014.

6 Petroleum Baseline: Carbon Intensity (g CO2 e/mj) of Petroleum will Increase Significantly due to Resource Shift Towards Tight Oil Source: Susan Boland, Stefan Unnasch; Carbon Intensity of Marginal Petroleum and Corn Ethanol Fuels ; Life Cycle Associates, 2014.

7 Corn Ethanol/Biofuels Baseline: iluc Debate Since RFS2: Recent analyses demonstrate potential ILUC emissions are substantially lower than initially estimated by U.S. EPA and others Source: Argonne National Laboratory, 10/2013 7

8 iluc Developments since RFS2 Implementation Argonne GREET model was updated to allow land use change emissions assessments via the CCLUB interface. The CCLUB model includes calculations that take soil carbon emissions and sequestration effects from land use change (LUC) into account. The results are widely published, and the published results in turn were validated by other institutions in separate peer reviewed publications. Purdue University reviewed several LUC emissions factor models concludes that those iluc emissions factor models (such as CCLUB) that properly account for soil carbon changes in land cover and tillage practices result in much lower emissions than other models. For selected modeling runs (that take realistic, projected crop yield increases into account) the LUC emissions in CCLUB for corn ethanol total 9.0 gco2e/mj (as opposed to 28 gco2e/mj used by EPA for corn ethanol)

9 Biofuels Baseline: Technology Adoption Since RFS2 Implementation Despite a general lack of investment in energy technologies in other industrial sectors during the recent economic downturn, ethanol plants kept investing in new technologies. Our extensive interaction with the plants during the survey process revealed that the continued adoption of new technologies is at least partially attributable to incentives and market certainty provided by the RFS. 2012/2013 Corn Ethanol 2008 Corn Ethanol Yield (anhydrous/undenatured, gallon/bushel) Thermal Energy (Btu/gallon, LHV) 23,862 26,206 Electricity Use (kwh/gallon) DDG Yield (dry basis) including corn oil (lbs/bu) Corn Oil Separated (lbs/bushel) Water Use (gallon/gallon)

10 Implementing Latest Data Sets: CI of gasoline and corn ethanol consumed in the U.S. over time. Modeling runs using latest LCA boundary science for the co-product treatment of corn stover (as supply of corn replacement feed & cellulosic ethanol production) and assumed blending requirements set by the RFA for corn and cellulosic ethanol will result in CI of corn based fuels of 39.3 gco2e/mj by This includes iluc assumptions of 9 gco2e/mj assessed with CCLUB In fact actual CI of corn ethanol was lower in the era than EPA assumed it would be in 2022

11 GHG Reductions from Corn Ethanol

12 RFS 2 Savings in 2013: 2.2% of US Transportation Emissions Total Emissions in 2012 = 6,526 Million Metric Tons of CO 2 equivalent Inventory of U.S. Greenhouse Gas Emissions and Sinks: Source: Latest GHG Report is for 2012, report released April 2014 Transportation Emissions: 0.28*6,526 million metric tons = 1,827 million metric tons RFS2 Savings: 40/1,827=2.2% of Transportation Emissions

13 In Summary Where is the Carbon Intensity of the Petroleum Mix Going CI of Petroleum Mix by 2022 is not 93 gco2/mj but 97 gco2/mj Where is the Carbon Intensity of Corn Ethanol/Biofuels Going CI of Corn Based Fuel Mix by 2022 is 39.3 gco2e/mj. This includes iluc Therefore, by 2022 corn ethanol constitutes a 39.3/97 gco2e/mj or 60% reduction from petroleum baseline, on par with advanced biofuels under RFS2

14 Questions Steffen Mueller University of Illinois at Chicago Stefan Unnasch Life Cycle Associates, LLC