Long-term bioethanol system and its implications on GHG emissions: a case study of Thailand.

The study evaluates greenhouse gas (GHG) emissions performance of future bioethanol systems in Thailand to ascertain whether bioethanol for transport could help the country mitigate a global warming impact. GHG emission factors of bioethanol derived from cassava, molasses, and sugar cane are analyzed using 12 scenarios covering the critical variables possibly affecting the GHG performance, i.e., (1) the possible direct land use change caused by expanding feedstock cultivation areas; (2) types of energy carriers used in ethanol plants; and (3) waste utilization, e.g., biogas recovery and dry distillers grains with solubles (DDGS) production. The assessment reveals that GHG performance of a Thai bioethanol system is inclined to decrease in the long run due to the effects from the expansion of plantation areas to satisfy the deficit of cassava and molasses. Therefore, bioethanol will contribute to the country's strategic plan on GHG mitigation in the transportation sector only if the production systems are sustainably managed, i.e., coal replaced by biomass in ethanol plants, biogas recovery, and adoption of improved agricultural practices to increase crop productivity without intensification of chemical fertilizers. Achieving the year 2022 government policy targets for bioethanol with recommended measures would help mitigate GHG emissions up to 4.6 Gg CO(2)-eq per year.

[1]  Thailand. Kǭng Sētthakit Kānkasēt.  Agricultural statistics of Thailand , 1955 .

[2]  B. Dale,et al.  Biofuels, land use change, and greenhouse gas emissions: some unexplored variables. , 2009, Environmental science & technology.

[3]  Mohamed Gabra.  Sugarcane Residual Fuels : a viable substitute for fossil fuels in the Tanzanian sugar industry , 1995 .

[4]  Shabbir H. Gheewala,et al.  Life cycle assessment of fuel ethanol from cane molasses in Thailand , 2008 .

[5]  Francesco Cherubini,et al.  GHG balances of bioenergy systems – Overview of key steps in the production chain and methodological concerns , 2010 .

[6]  B. Dale,et al.  Cumulative Energy and Global Warming Impact from the Production of Biomass for Biobased Products , 2003 .

[7]  Shabbir H. Gheewala,et al.  Fossil energy savings and GHG mitigation potentials of ethanol as a gasoline substitute in Thailand , 2007 .

[8]  Kaye E. Basford,et al.  The availability of nitrogen from sugarcane trash on contrasting soils in the wet tropics of North Queensland , 2006, Nutrient Cycling in Agroecosystems.

[9]  Shabbir H. Gheewala,et al.  Greenhouse gas emissions from production and use of used cooking oil methyl ester as transport fuel in Thailand , 2009 .

[10]  T. Buchholz,et al.  Sustainability criteria for bioenergy systems: results from an expert survey , 2009 .

[11]  Reinout Heijungs,et al.  A greenhouse gas indicator for bioenergy: some theoretical issues with practical implications , 2009 .

[12]  Bruno Peuportier,et al.  How to account for CO2 emissions from biomass in an LCA , 2007 .

[13]  Thapat Silalertruksa,et al.  Environmental sustainability assessment of bio-ethanol production in Thailand , 2009 .

[14]  Jinyue Yan,et al.  Biofuels in Asia , 2009 .

[15]  Vincent Mahieu,et al.  Well-to-wheels analysis of future automotive fuels and powertrains in the european context , 2004 .

[16]  Thapat Silalertruksa,et al.  Security of feedstocks supply for future bio-ethanol production in Thailand , 2010 .

[17]  A. Faaij,et al.  Different palm oil production systems for energy purposes and their greenhouse gas implications , 2008 .

[18]  Mary Ann Curran,et al.  Studying the effect on system preference by varying coproduct allocation in creating life-cycle inventory. , 2007, Environmental science & technology.

[19]  S. Gheewala,et al.  Impacts of Thai bio-ethanol policy target on land use and greenhouse gas emissions , 2009 .

[20]  S. Polasky,et al.  Land Clearing and the Biofuel Carbon Debt , 2008, Science.

[21]  Pushpam Kumar.  Agriculture (Chapter8) in IPCC, 2007: Climate change 2007: Mitigation of Climate Change. Contribution of Working Group III to the Fourth assessment Report of the Intergovernmental Panel on Climate Change , 2007 .

[22]  B. Dale,et al.  Life cycle assessment of various cropping systems utilized for producing biofuels: Bioethanol and biodiesel , 2005 .

[23]  Shabbir H. Gheewala,et al.  Greenhouse gas savings potential of sugar cane bio-energy systems , 2010 .

[24]  M. Curran,et al.  A review of assessments conducted on bio-ethanol as a transportation fuel from a net energy, greenhouse gas, and environmental life cycle perspective , 2007 .

[25]  E. Hizsnyik,et al.  Biofuels and Food Security: Implications of an Accelerated Biofuels Production , 2009 .

[26]  Martin Junginger,et al.  Overview of recent developments in sustainable biomass certification , 2007 .

[27]  Electo Eduardo Silva Lora,et al.  Biofuels: Environment, technology and food security , 2009 .

[28]  Francesco Cherubini,et al.  Energy- and greenhouse gas-based LCA of biofuel and bioenergy systems: Key issues, ranges and recommendations , 2009 .

[29]  J. Germer,et al.  Estimation of the impact of oil palm plantation establishment on greenhouse gas balance , 2008 .

[30]  Keat Teong Lee,et al.  Life cycle assessment of palm biodiesel: Revealing facts and benefits for sustainability , 2009 .

[31]  Rainer Zah,et al.  International trade in biofuels: an introduction to the special issue , 2009 .

[32]  K. Sriroth,et al.  The promise of a technology revolution in cassava bioethanol: From Thai practice to the world practice , 2010 .

[33]  Shabbir H. Gheewala,et al.  Life cycle assessment of fuel ethanol from cassava in Thailand , 2008 .

[34]  Hans-Jürgen Dr. Klüppel,et al.  The Revision of ISO Standards 14040-3 - ISO 14040: Environmental management – Life cycle assessment – Principles and framework - ISO 14044: Environmental management – Life cycle assessment – Requirements and guidelines , 2005 .

[35]  M. Huijbregts,et al.  Palm oil and the emission of carbon-based greenhouse gases , 2008 .