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Rice, as a main crop, contributes to food security in Asia. However, its by-product, rice straw, poses challenges as it is often disposed of unsustainably. This research investigates the environmental performance of a 1000 m3 rice straw biogas pilot plant in Laguna, Philippines. A lifecycle assessment identified the climate change impact of the biogas system, straw burning and soil incorporation. In addition to GWP100, the global temperature potential's dynamic climate effects were assessed, including integrated radiative forcing and instantaneous temperature effects. The timeframe of the biogenic emission fluxes of rice production is particularly relevant as the sequestered CO 2 during plant growth is partly released as methane and CO 2 , depending on the straw management practices. Straw burning had the highest net emission impact. However, straw incorporation has the highest short-term radiative forcing and temperature increase. The biogas system provided significant short- and long-term GHG emission reduction of up to 68 % when biogas replaced burning or soil incorporation and the use of fossil fuels. Still, considerable uncertainties remain about fugitive methane emissions, handling and post-processing of the digestate. While single GHG emission figures on a GWP100 basis are useful for informing decision-making, this single-metric approach limits understanding of rice production's short- and long-term impacts. Additionally, our assessment emphasises the necessity for governance frameworks that promote sustainable practices in rice farming, as banning rice straw burning may result in less favourable outcomes from soil incorporation, whereas integrating biogas offers a solution benefiting rice-growing communities and global sustainability efforts. • Biogas from rice straw reduces emissions by up to 69 %. • Soil incorporation of straw has highest short-term (20 years) temperature increase. • Assessing more than one metric and timeframe supports more informed decision-making. • Governance frameworks enabling bioenergy integration support SDG 3, 7 and 13. [ABSTRACT FROM AUTHOR]

The European Union relies largely on bioenergy to achieve its climate and energy targets for 2020 and beyond. We assess, using Attributional Life Cycle Assessment (A-LCA), the climate change mitigation potential of three bioenergy power plants fuelled by residual biomass compared to a fossil system based on the European power generation mix. We study forest residues, cereal straws and cattle slurry. Our A-LCA methodology includes: i) supply chains and biogenic-CO 2 flows; ii) explicit treatment of time of emissions; iii) instantaneous and time-integrated climate metrics. Power generation from cereal straws and cattle slurry can provide significant global warming mitigation by 2100 compared to current European electricity mix in all of the conditions considered. The mitigation potential of forest residues depends on the decay rate considered. Power generation from forest logging residues is an effective mitigation solution compared to the current EU mix only in conditions of decay rates above 5.2% a −1 . Even with faster-decomposing feedstocks, bioenergy temporarily causes a STR(i) and STR(c) higher than the fossil system. The mitigation potential of bioenergy technologies is overestimated when biogenic-CO 2 flows are excluded. Results based solely on supply-chain emissions can only be interpreted as an estimation of the long-term (>100 years) mitigation potential of bioenergy systems interrupted at the end of the lifetime of the plant and whose carbon stock is allowed to accumulate back. Strategies for bioenergy deployment should take into account possible increases in global warming rate and possible temporary increases in temperature anomaly as well as of cumulative radiative forcing. [ABSTRACT FROM AUTHOR]

This study aims to quantify the environmentally sustainable and economically feasible potentials of agricultural and agro-industrial residues to generate electricity via direct combustion in centralised power plants in Brazil. Further, the energy savings and greenhouse gas (GHG) reduction potential of replacing natural gas-based electricity by bioenergy have been assessed. To this end, a methodology has been developed based on an integrated evaluation, incorporating statistical and geographical information system (GIS)-based analysis, and a life-cycle-assessment approach. Results reveal that the environmentally sustainable generation potential is nearly 141 TWh/year, mainly concentrated in the South, Southeast, and Midwest regions of the country. Sugarcane, soybean and maize crop residues are the major feedstocks for available bioenergy. On the other hand, the economic potential is far lower, accounting to 39 TWh/year. The total GHG mitigation is nearly 18 million tonne CO 2 e and could reach 64 million tonne CO 2 e yearly, if the technical potential is considered. The gap between technical and economic potentials implies that constraints to bioenergy are not related to a lack of resources, but rather associated to economic, logistical, regulatory and political barriers. [ABSTRACT FROM AUTHOR]