Potential for Sustainable Deployment of Biofuels Under EISA

Transcription

1 Potential for Sustainable Deployment of Biofuels Under EISA American Chemical Society Science & the Congress Briefing on Cellulosic Biofuels Virginia H. Dale Oak Ridge National Laboratory Washington, D.C. January 30, 2012

2 Looking at the biofuel supply chain in terms of sustainability indicators Feedstock production Feedstock logistics Conversion to biofuel Biofuel logistics Biofuel End uses Land conditions Harvesting and collection Conversion process Transport Engine type and efficiency Feedstock type Processing Fuel type Storage Blend conditions Management Storage Co-products Based on McBride et al. (2011) and Dale et al. (in review) 2 Managed by UT-Battelle Transport Environmental Socioeconomic Soil quality Profitability Water Social well being Greenhouse gases External trade Biodiversity Energy security Air quality Resource conservation Productivity Social acceptability Categories without major effects

3 Ready access to biomass sugars can reduce cost of processing cellulosic biomass Approach Develop modified or natural biomass that is designed to release sugars more easily Engineer microbes to consolidate multiple costly processes into a single step Recalcitrance: Resistance to breakdown into sugars Fuel(s) Outcomes to date Modified biomass: Switchgrass Yields 30% more biofuel Requires less commercial enzyme Now in commercial field trials Improved yeast: Field trials of modified switchgrass at Ceres facility Combines ability to digest cellulose and ferment Now the basis of a commercial plant Cellulosic biomass Sugars Prognosis: Needed technology improvements will impact industry within the next 5 years Source: U.S. Department of Energy BioEnergy Science Center ( 3 Managed by UT-Battelle

4 Evaluate land-use effects based on empirical evidence Land use is dynamic and bioenergy contributes to ongoing land-use change Initial change drivers (cultural, technical, biophysical, political, economic, demographic) Initial land-use change Land cover (typically measured by remote sensing methods at one place and time) Demand Ongoing land-use changes Filters: Land-cover data, scale, sources Filters: Private land, rents Global economic models Prices, quantities, and distribution of goods Filters: Land-cover, carbon change data Carbon stocks Source: CBES 2010 ( Subsequent change drivers Area (Mha) Area (Mha) No empirical evidence for land-use changes due to bioenergy Cultivated crop land Range land Forest land Non cultivated crop land CRP land Pasture land Developed land Based on data from USDA 2009-NRI (Dale et al. 2011), supported by recent USDA reports

5 Compare bioenergy to other energy alternatives Environmental effects associated with gasoline production 1. Establish fuel sources 2. Obtain raw material 3. Distribute raw material 4. Produce fuel Projected environmental effects of ethanol production Temporal scale (days) 100,000 1, Produce gasoline 1. Explore for oil 2. Extract oil 3. Distribute crude oil 4. Produce biofuel 2. Harvest and collect biomass 1. Establish biomass feedstock 3. Distribute biomass ,000,000 Field Region Globe 5 Managed by UT-Battelle Spatial scale (km 2 ) ,000,000 Field Region Spatial scale (km 2 ) Stommel diagrams show spatial extent and duration of effects (Parish et al., in prep)

6 Adopt landscape perspective Consider fuel production within entire system (interactions and feedbacks) as an opportunity to design landscapes that add value Dale et al. (2010) 6 Managed by UT-Battelle

7 An optimization model can identify ideal sustainability conditions Spatial optimization model Identifies where to locate plantings of bioenergy crops given feedstock needs for Vonore refinery Considering Farm profit Water quality constraints Parish et al., Biofuels, Bioprod. Bioref. 6,58 72 (2012) 7 Managed by UT-Battelle

8 Balancing objectives: A landscape design of cellulosic bioenergy crop plantings may simultaneously improve water quality and increase profits for farmer-producers while achieving a feedstock-production goal Percent achieved Objective: Ag land converted Max N reduction Total Profit Reduction in N Reduction in P Reduction in Sediment Max P reduction Max sed reduction Max profit Balanced <25% ag conversion 58% 51% 44% 27% 60% 25% Land area recommended for switchgrass in this watershed: 1.3% of the total area (3,546 ha of 272,750 ha) 8 Managed by UT-Battelle

9 Recognize place-based options Residue availability is specific to each place and management Wilhelm et al. (2007) Collectable stover: 64M tons/year Dry tons <1,000 1,000 50,000 50, , , , , ,000 >400,000 Collectable stover if tillage practices change: 111M tons/year Different crops grow better in specific places Hybrid poplars Switchgrass Sorghum Switchgrass Hybrid poplars Miscanthus Sorghum Switchgrass Hybrid poplars Switchgrass Willows Dale et al. (2011) Hybrid poplars Miscanthus Pine Sorghum Sweetgum Switchgrass Energy cane Ecalyptus Pine

10 Thank you! 10 Managed by UT-Battelle