Sustainability promised by biofuels has been questioned after widespread adoption led to using land and agricultural products for fuel instead of food or livestock feed. Life cycle analysis (LCA) provides an objective, scientific basis for answering these questions according to Professor Dr. Shabbir Gheewala, Joint Graduate School of Energy and Environment (JGSEE) at King Mongkut's University of Technology Thonburi (KMUTT). LCA is also helpful in refuting preconceptions that might otherwise influence decision makers, such as the incorrect assumption that reducing greenhouse gas emissions and avoiding negative impact on the environment reduces long-term productivity or profitability. In other words, LCA and related tools evaluate the total economic and environmental impact of a product throughout the entire production and, optionally, the consumption and disposal or recycling process.
For biofuel production, like production of bioethanol from sugarcane, Dr. Shabbir, together with JGSEE’s Dr. Thapat Silalertruksa and Ms. Patcharaporn Pongpat, assessed planting, growing and harvesting the sugarcane, transporting it to a biorefinery, and making bioethanol, sugar and other products at the biorefinery. The assessment process generally starts with a site visit to establish contact with production workers, particularly managers and operations engineers, and walk through the production process. Then the research team sends questionnaires to collect detailed data about the production inputs, including materials, energy, and labor, production procedures, including emissions, working conditions, and waste, and products. After initial analysis of the data, the LCA team follows up with a second site visit to interview key production works to complete any missing data. Analysis continues, in part, by checking to make sure that the mass and energy going into the production process balances the mass and energy leaving the production system. Then the LCA team confirms that the analysis matches the actual situation with a final site visit before fine tuning the analysis by evaluating uncertainty and the sensitivity of the results to alternate assumptions. Finally, Dr. Shabbir and the LCA team prepare recommendations and present them to decision makers.
Agriculture causes about 20-35% of the greenhouse gas emissions from human activity. In addition to the production of bioethanol from sugarcane, Dr. Shabbir and his Life Cycle Sustainability Assessment Laboratory assessed the sustainability of biodiesel produced from palm oil. Even as 2016 was the hottest year on record, Dr. Shabbir leads the development of the Research Network on Food, Fuel, and Climate Change (FFCC) to build LCA capacity throughout Thailand. The FFCC Research Network, supported by the National Science and Technology Development Agency’s (NSTDA), also provides food and fuel policy recommendations related to climate change and promotes university research-based planning for industry and policy makers. Finally, under Dr. Shabbir’s mentorship, the FFCC Research Network trains industry managers and operations engineers in support of sustainable competitiveness.
Dr. Shabbir’s expertise has been recognized internationally and nationally. He was awarded the NSTDA 2016 Research Chair Grant on 28 December, 2016 and serves on the editorial boards of the International Journal of Life Cycle Assessment, Energy for Sustainable Development, and the Journal of Sustainable Energy and Environment.
Recommendations for More Sustainable Sugar, Ethanol and Electric Power Production in Thai Sugarcane Biorefineries
• Stop cane trash burning in the fields before harvesting. Instead, use green cane harvesting techniques and leave the leaves and tops of the sugarcane on the ground as organic matter.
• Mechanize planting and harvesting for planted areas over 0.8 hectares and plantings on suitable land with 150 cm row spacing and only when offsetting increased fossil fuel use by burning cane trash. This also helps farmers be less vulnerable to labor shortages during harvest.
• Collect approximately 50% of cane trash from the fields and transport it to the biorefinery to be burned to produce electric power via a steam turbine for use in the biorefinery and return the excess to the local electric grid. The correct proportion of cane trash to remove depends on local soil conditions.
• Use the remaining cane trash as organic matter to maintain soil quality.
• Concentrate and use vinasse (the watery byproduct produced by bioethanol distillation from sugar) as a fertilizer and soil conditioner.