Environmental implications associated with sweet sorghum production and use for biofuels

Transcription

1 ifeu Institute for Energy and Environmental Research Heidelberg Environmental implications associated with sweet sorghum production and use for biofuels Nils Rettenmaier EUROCLIMA Workshop Campinas, Brazil, 30 November 2011

2 Background Assessment of energy and greenhouse gas inventories of Sweet Sorghum for first and second generation bio-ethanol Susanne Köppen Guido Reinhardt Sven Gärtner Commissioned by the Food and Agriculture Organization (FAO) Heidelberg, March 2009 ifeu Institut für Energieund Umweltforschung Heidelberg ggmbh Assessment of energy and greenhouse gas inventories of Sweet Sorghum for first and second generation bioethanol Report commissioned by the Food and Agriculture Organization (FAO), Rome Authors: Susanne Köppen, Guido Reinhardt, Sven Gärtner Final report: March 2009

3 Characteristics of Sweet Sorghum Sorghum bicolor Geographical distribution: in semi-arid to humid climates; 40 N to 40 S Physical characteristics: Annual; grows from seeds; stalk contains a sugar-rich juice (sucrose, fructose, glucose); panicles produce up to starch containing grains. C4 crop, very drought resistant; good adaptability to poor soil types and to saline soils; very short vegetation period and thus is ideal for double cropping.

4 Characteristics of Sweet Sorghum Crop part Possible use options Grains Feed, food, 1 st generation bioethanol Juice Sugar, 1 st generation bioethanol Bagasse Feed, pulp, bioenergy, 2 nd generation bioethanol, compost, fertilizer IFEU 2009

5 Outline Introduction Life cycle assessment (LCA) methodology Energy and GHG balances of Sweet Sorghum EtOH Sweet Sorghum vs. fossil fuel main scenarios Sweet Sorghum vs. fossil fuel sensitivity analyses Sweet Sorghum vs. other ethanol crops Additional environmental impacts Conclusions Outlook: The SWEETFUEL project

6 Sw. sorghum ethanol vs. fossil fuel Seeds Miner. Fert. Pesticides Diesel fuel Sweet Sorghum Grains Juice Bagasse Combustion Power / Heat Bioenergy Convent. power production Lime Auxiliary products Conversion Vinasse Stillage Fusel oils Soy meal Soy meal Convent. heat production Ethanol from grains Ethanol from juice Calcium carbonate Mineral fertilizer IFEU 2009

7 Sw. sorghum ethanol vs. fossil fuel Greenhouse effect Credits Expenditures Sweet Sorghum ethanol Fossil gasoline Advantage for bioethanol Disadvantages Balance t CO 2 equiv. / (ha*yr) Expenditures: Credits: Fossil fuel: Machine work Agricultural system Transport biomass Ethanol production Transport ethanol Ethanol usage Lime Vinasse/stillage Fusel oil Power Fossil equiv. production Fossil equiv. usage IFEU 2009

8 Sw. sorghum ethanol vs. fossil fuel Energy savings Credits Expenditures Sweet Sorghum ethanol Fossil gasoline Advantage for bioethanol Disadvantages Balance GJ PE / (ha*yr) Expenditures: Credits: Fossil fuel: Machine work Agricultural system Transport biomass Ethanol production Transport ethanol Ethanol usage Lime Vinasse/stillage Fusel oil Power Fossil equiv. production Fossil equiv. usage IFEU 2009

9 Overview on scenarios N Scenario Juice Grains Bagasse 1 Standard 1 st gen. bioethanol 1 st gen. bioethanol Process energy & bioelectricity 2 EtOH 2 extended autarkic 3 EtOH 2 maximum fossil 1 st gen. bioethanol 1 st gen. bioethanol 2 nd gen. bioethanol (autarkic) 1 st gen. bioethanol 1 st gen. bioethanol 2 nd gen. bioethanol (fossil fuel input) 4 Grains food 1 st gen. bioethanol Food Process energy & bioelectricity 5 Food & EtOH 2 1 st gen. bioethanol Food 2 nd gen. bioethanol (autarkic) 6 Grains & juice food Food (fossil fuel input) Food 2 nd gen. bioethanol (autarkic) IFEU 2009

10 Sw. sorghum ethanol vs. fossil fuel 1 Standard 2 EtOH 2 extended autarkic 3 EtOH 2 max. t CO 2 equiv. / (ha*yr) 4 Grains food 5 Food & EtOH 2 6 Grains & juice food Standard 2 EtOH 2 extended autarkic 3 EtOH 2 max. GJ PE / (ha*yr) Grains food 5 Food & EtOH 2 6 Grains & juice food IFEU 2009

11 Outline Introduction Life cycle assessment (LCA) methodology Energy and GHG balances of Sweet Sorghum EtOH Sweet Sorghum vs. fossil fuel main scenarios Sweet Sorghum vs. fossil fuel sensitivity analyses Sweet Sorghum vs. other ethanol crops Additional environmental impacts Conclusions Outlook: The SWEETFUEL project

12 1. Agricultural reference system Conventional fuel Sweet Sorghum bioethanol Auxilliary Products Crude oil extraction and pre-treatment Cultivation Alternative land use or land cover Transport Processing Transport Milling Fermentation Dehydration Vinasse Power Feed Conventional feed production (soy meal) Conventional power production Gasoline Bio- Ethanol Product Process Equivalent Product IFEU 2009

13 1. Agricultural reference system Europe: expanding domestic biomass production for biofuel (1) (certified) good practise production of biomass (2) replaces previously given cultivation on the same acreage, e.g. animal food INDIRECT INDUCTION OF FOREST LOGGING (4) the required area for animal food production is likely to be forest (3) animal food will be imported increasingly, e.g. from tropical countries Fehrenbach et al. 2008

14 1. Agricultural reference system Conventional fuel Sweet Sorghum bioethanol Auxilliary Products Fallow Europe Crude oil extraction and pre-treatment Transport Cultivation Transport Wheat Europe Soy Europe Wheat USA Soy Brazil US prairie Brazilian rainforest Processing Milling Fermentation Dehydration Vinasse Power Feed Conventional feed production (soy meal) Conventional power production Gasoline Bio- Ethanol Product Process Equivalent Product IFEU 2009

15 1. Agricultural reference system Greenhouse effect Advantage Disadvant. for bioethanol Standard Replacement wheat to US prairie Replacement soy to Brazilian forests t CO 2 equiv. / (ha*yr) IFEU 2010

16 2. Different yields Ancillary products Cultivation Leaves Feed Wheat Grains Juice Bagasse Transport Stillage Feed Soy meal Processing (e. g. milling, fermentation, combustion) Vinasse Bioenergy Fuseloil Feed Power Heat Soy meal Convent. prod. power Convent. prod. heat Calcium carbonate Fertiliser Mineral fert. (N, P) Bio- Ethanol Fuel Gasoline Product Process Equivalent Product Option IFEU 2009

17 2. Different yields Greenhouse effect Advantage for bioethanol Low biomass yield Medium biomass yield High biomass yield Low juice yield High juice yield t CO 2 equiv. / (ha*yr) IFEU 2009

18 3. Substituted energy carriers Ancillary products Cultivation Leaves Feed Wheat Grains Juice Bagasse Transport Stillage Feed Soy meal Processing (e. g. milling, fermentation, combustion) Vinasse Bioenergy Fusel oil Feed Power Heat Soy meal Convent. prod. power Convent. prod. heat Calcium carbonate Fertiliser Mineral fert. (N, P) Bio- Ethanol Fuel Gasoline Product Process Equivalent Product Option IFEU 2009

19 3. Substituted energy carriers Greenhouse effect Credits Expenditures Coal (standard) Natural gas Fossil equivalent Advantage for ethanol Disadvantages Coal (standard) Natural gas t CO 2 equiv. / (ha*yr) Expenditures: Credits: Fossil fuel: Biomass production Ethanol credits Foss. equiv. EtOH grain Balance Biomass transport Ethanol production Credit power Foss. equiv. EtOH juice Ethanol transport Ethanol usage IFEU 2009

20 4. External energy carriers Scenario EtoH 2 max. Seeds Miner. Fert. Pesticides Diesel fuel Sweet Sorghum Grains Juice Bagasse Coal Vinasse Soy meal Lime Conversion Stillage Soy meal Auxiliary products Fuseloils Calcium carbonate Convent. heat production Mineral fertilizer Ethanol grains Ethanol juice Ethanol bagasse IFEU 2009

21 4. External energy carriers Greenhouse effect Credits Expenditures Coal (standard) Natural gas Fossil equivalent Advantage Disadvantages f. bioethanol Coal (standard) Natural gas t CO 2 equiv. / (ha*yr) Expenditures: Credits: Fossil fuel: Biomass production Ethanol credits Foss. equiv. EtOH grain Balance Biomass transport Ethanol production Credit power Foss. equiv. EtOH juice Ethanol transport Ethanol usage IFEU 2009

22 Outline Introduction Life cycle assessment (LCA) methodology Energy and GHG balances of Sweet Sorghum EtOH Sweet Sorghum vs. fossil fuel main scenarios Sweet Sorghum vs. fossil fuel sensitivity analyses Sweet Sorghum vs. other ethanol crops Additional environmental impacts Conclusions Outlook: The SWEETFUEL project

23 Comparison with biofuel GJ PE / (ha*yr) Advantage for bioethanol Primary energy Greenhouse effect EtOH corn EtOH wheat EtOH sugar beet 1st generation EtOH potatoe EtOH sugar cane EtOH sweet sorghum EtOH poplar EtOH triticale 1st & 2nd generation 2nd generation t CO 2 equiv. / (ha*yr) IFEU 2010

24 Outline Introduction Life cycle assessment (LCA) methodology Energy and GHG balances of Sweet Sorghum EtOH Sweet Sorghum vs. fossil fuel main scenarios Sweet Sorghum vs. fossil fuel sensitivity analyses Sweet Sorghum vs. other ethanol crops Additional environmental impacts Conclusions Outlook: The SWEETFUEL project

25 Environmental impacts of biofuels Like with any other product, a number of environmental impacts are usually associated with the production and use of biomass for biofuel. The main environmental concerns related to biofuels are land use and associated impacts on natural environment and resources such as GHG emissions, biodiversity, water and soil. A number of assessment techniques are available for environmental assessment which differ in the subject of study and show strengths and weaknesses

26 Review of environmental studies criteria communication management risk social aspects SocioEco- Effiency Analysis economics comprehensive environmental aspects single environmental aspects material flow analysis test on chemicals LCA PCF Eco- efficiency analysis eco audit eco audit technology assessment EIA SEA subject of study substance material product production site project technology policies plans programs LCA is less suitable for site-specific env. impacts

27 Other environmental impacts Impact parameter Sweet Sorghum production systems Large-scale Small-scale/ low input Acidification - - Eutrophication - 0 to - Ozone depletion - - Photo smog - - Soil erosion/ soil compaction -/ - -/ 0 Water consumption + + Impact on ground and surface water 0 to - 0 Impact on soil + to - + to - (Agro-)Biodiversity 0 to - 0 to + + positive; 0 no impact; negative LCA EIA

28 10,0 7,5 5,0 2,5 0,0 I Example: EIA of energy crops in EU II III II III II III I II III II III II III II III I I I I I III III II I II III II III I II I I I Emissions Soil Resources Waste Biodiversity Landscape II III II III I I II II III I III II III II III I I I II III Weighted and normalized scores Rapeseed (NEM, CON, ATN, ATC, LUS) Sunflower (MDN) Ethiopian mustard (MDS) Sugar beet (CON, ATC) Sweet sorghum (LUS, MDN, MDS) Hemp (NEM, ATN, LUS, MDN) Flax (CON, ATC, MDS) Reed canary grass (NEM) Miscanthus (CON, ATN, ATC, LUS) Switchgrass (ATN, ATC) Giant reed (MDN) Cardoon (MDS) Poplar (NEM, ATC, MDN) Willow (CON, ATN, LUS) Eucalyptus (LUS, MDS) Wheat (all regions) Potato (all regions) Fallow (all regions) Fernando et al. 2010

29 Conclusions Sweet Sorghum bioethanol can contribute significantly to the conservation of fossil energy resources and to the mitigation of greenhouse gases. Also combination of 1 st and 2 nd generation bioethanol leads to savings of energy and greenhouse gases If grains are used as food, bioethanol from the stalk s sugar juice still shows clear advantages to fossil fuels. Only crop to combine food and bioenergy production with available technologies

30 Outline Introduction Life cycle assessment (LCA) methodology Energy and GHG balances of Sweet Sorghum EtOH Sweet Sorghum vs. fossil fuel main scenarios Sweet Sorghum vs. fossil fuel sensitivity analyses Sweet Sorghum vs. other ethanol crops Additional environmental impacts Conclusions Outlook: The SWEETFUEL project

31 Conclusions Sweet Sorghum bioethanol can contribute significantly to the conservation of fossil energy resources and to the mitigation of greenhouse gases. Also combination of 1 st and 2 nd generation bioethanol leads to savings of energy and greenhouse gases If grains are used as food, bioethanol from the stem s sugar juice still shows clear advantages to fossil fuels. Only crop to combine food and bioenergy production with available technologies

32 Conclusions If both sugar and grains are used as food, all energy and greenhouse gas expenditures can be compensated by ethanol production from the bagasse (2 nd generation).

33 Conclusions Optimization potentials: If 1 st and 2 nd generation bioethanol are to be combined, part of the bagasse should be used for process energy generation Land use change: indirect land use change due to the replacement of food or feed crops can lead to significant carbon emissions and thus to a disadvantageous greenhouse gas balance; Sweet sorghum should not compete with food/feed production

34 Conclusions Optimization potentials: Yields: higher biomass yields can lead to higher savings in energy and greenhouse gases Energy carrier: the higher the specific emissions of greenhouse gases are in the replaced energy carriers, the better results can be obtained by replacing it. In comparison with other ethanol crops no clear advantage or disadvantage; depends on specific boundary conditions

35 Outline Introduction Life cycle assessment (LCA) methodology Energy and GHG balances of Sweet Sorghum EtOH Sweet Sorghum vs. fossil fuel main scenarios Sweet Sorghum vs. fossil fuel sensitivity analyses Sweet Sorghum vs. other ethanol crops Additional environmental impacts Conclusions Outlook: The SWEETFUEL project

36 Outlook Sweet Sorghum an alternative energy crop EU FP7 project (no ) Duration: 01/ /2013 (60 months) Total budget: 4.9 M (EC contrib.: 3.0 M ) Coordinator: CIRAD Sweet Fuel Partners: ICRISAT, EMPRABA, KWS, UNIBO, UCSC, ARC-CGI, UANL, WIP Objective: Develop bio-ethanol production in temperate and semi- arid regions from sweet sorghum through genetic enhancement and improvement of cultural and harvest practices

37 Sweet Fuel Sweet sorghum : an alternative energy crop 1/8 Project Number: Web site:

38 Sweet Fuel Organisation of WPs WP5 CULTURAL PRACTICES & CROP MODELLING WP4 FUNCTIONAL ANALYSIS MANAGEMENT OF THE PROJECT Expert in ethics WP6 BREEDING EFFORT WP1 Low Temp. Marginal Soils WP3 WP2 Drought INTEGRATED ASSESSMENT WP8 WP7 DISSEMINATION OF ESULTS STAKE HOLDERS 5/8 Project Number: Web site:

39 Sweet Fuel Breeding objectives Target ideotype for WP1 Sorghum with high biomass, good adaptation to low temperature and good digestibility (low content of lignin, bmr trait) suitable for 2 nd generation bioethanol Specific objectives of breeding programmes WP1, WP2 and WP3 are to develop new sorghum lines or hybrids. The target ideotype depends on the target environment as well as the system of transformation Target ideotype for WP2 Double purpose sorghum (grain + sugars) suitable for humane and/or animal feeding, with a good drought adaptation, juicy stalks with high sugar content and good digestibility suitable for 1 st generation bioethanol Target ideotype for WP3 Double purpose sorghum (grain + sugars) suitable for humane and/or animal feeding, with a good adaptation to marginal soils (acidity, high Al, low P) and good digestibility suitable for 1 st generation bioethanol 6/8 Project Number: Web site:

40 Sweet Fuel Other objectives Other specific objectives of SweetFuel are: WP6 Provide a multicriteria evaluation of the sustainability of the bioethanol production from sweet sorghum on a social, economic and environmental point of view Task 6.1 Definitions and settings & Technological assessment Task leader: CIRAD Tasks Environmental assessment Task leader: IFEU Economic assessment Task leader: ICRISAT SWOT analysis Task leader: WIP Task 6.5 Integrated assessment of sustainability Task leader: IFEU 7/8 Project Number: Web site:

41 Sweet Fuel SWEETFUEL scenarios Basic life cycle comparison Seeds Diesel fuel Pesticides Fertiliser Irrigation Crude oil extraction & pretreatment Cultivation / Harvesting Alternative land use Mineral oil Milling By-product Conventional product Juice Processing (refining) Processing (e. g. fermentation, distillation) By-product Conventional product Gasoline Ethanol from juice Product Process Reference system

42 Sweet Fuel SWEETFUEL scenarios Semi-arid / tropical climate centralised Sweet sorghum crops are cultivated in villages and transported to central units where further processing steps follow Grains for feed / food in order to set off food security problems Bagasse used for process energy generation in ethanol production

43 Sweet Fuel Tropical climate centralised Seeds Diesel fuel Pesticides Fertiliser Irrigation Village level Cultivation / Harvesting Stalks Leaves Grains 1B 1C Fertilizer Feed Feed / Food Alternative land use N.P,K fertilizer Cereals 1 Cereals 1 Milling Juice Process energy Bagasse Surplus Bagasse 1a 1b Bioenergy Feed Conventional power Cereals 1 Vinasse Fertilizer N,P,K fertilizer Processing (fermentation, distillation) Fusel oil Calcium carbonate Heat Fertilizer Conventional heat Lime fertilizer Ethanol from juice Dehydration 1I Transport fuel Gasoline Processing Wood Ethanol 1 1II Fuel Paraffin LPG 1 needs to be discussed / clarified Scenario Option Process Product Reference system

44 Sweet Fuel SWEETFUEL scenarios Semi-arid / tropical climate decentralised Two levels of decentralisation: a) Syrup is cultivated from sweet sorghum juice in villages and transported to central ethanol units Bad infrastructure for biomass transportation might require partial local production and syrup is more advantageous for ethanol production as longer storable b) All production steps until ethanol processing are realized at village level Opportunity to gain access to own energy and to provide a healthier energy source than wood or paraffin; contribution to rural development Grains for feed / food in order to set off food security problems Bagasse used for process energy generation in syrup and ethanol production

45 Sweet Fuel Tropical climate decentralised I Seeds Diesel fuel Pesticides Fertiliser Irrigation Cultivation / Harvesting Stalks Leaves 2B 2C Fertilizer Feed Alternative land use N,P,K fertilizer Cereals 1 Milling Grains Feed / Food Cereals 1 2a Feed Cereals 1 Juice Processing Process energy Bagasse Surplus Bagasse 2b Bioenergy Conventional power Wood 2c Heat (Cooking) Parrafin Village level Syrup 2d Fertilizer LPG N,P,K fertilizer Vinasse Fertilizer N,P,K fertilizer Processing (fermentation, distillation) Fusel oil Calcium carbonate Heat Fertilizer Conventional heat Lime fertilizer Ethanol from juice Dehydration 2I Transport fuel Gasoline Processing Wood Ethanol 1 2II Fuel Paraffin LPG 1 needs to be discussed / clarified Scenario Option Process Product Reference system

46 Sweet Fuel Tropical climate decentralised II Seeds Diesel fuel Pesticides Fertiliser Irrigation Cultivation / Harvesting Leaves 3B 3C Fertilizer Feed Alternative land use N,P,K fertilizer Cereals 1 Grains Feed / Food Cereals 1 Stalks Milling Process energy Bagasse Surplus Bagasse 3a 3b Feed Bioenergy Cereals 1 Conventional power Wood Juice 3c Heat (Cooking) Paraffin LPG 3d Fertilizer N,P,K fertilizer Village level Processing (fermentation, distillation) Vinasse Fusel oil Calcium carbonate 3б 3е Feed Fertilizer Heat Fertilizer Cereals 1 N,P,K fertilizer Conventional heat Lime fertilizer Ethanol from juice 3I Transport fuel Gasoline Processing Wood Ethanol 1 3II Fuel Paraffin LPG 1 needs to be discussed / clarified Scenario Option Process Product Reference system

47 Sweet Fuel SWEETFUEL scenarios Temperate climate Only large scale centralised production Whole crop is used focus on high biomass yield instead of high sugar / juice yields Focus on 2 nd generation production technology Four pathways are assessed: a) Biogas production b) 2 nd generation ethanol production from lignocellulose c) Direct combustion d) Gasification for BtL-production

48 Thank you for your attention! Nils Rettenmaier Acknowledgement Part of this work was funded by the European Commission through the FP7 project SWEETFUEL (GA number ). Contact: / - 24 Sven Gärtner Guido Reinhardt Downloads: Susanne Köppen