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To meet Energy Independence and Security Act (EISA) cellulosic biofuel mandates, the United States will require an annual domestic supply of about 242 million Mg of biomass by 2022. To improve the feedstock logistics of lignocellulosic biofuels in order to access available biomass resources from areas with varying yields, commodity systems have been proposed and designed to deliver quality-controlled biomass feedstocks at preprocessing "depots". Preprocessing depots densify and stabilize the biomass prior to long-distance transport and delivery to centralized biorefineries. The logistics of biomass commodity supply chains could introduce spatially variable environmental impacts into the biofuel life cycle due to needing to harvest, move, and preprocess biomass from multiple distances that have variable spatial density. This study examines the uncertainty in greenhouse gas (GHG) emissions of corn stover logistics within a bio-ethanol supply chain in the state of Kansas, where sustainable biomass supply varies spatially. Two scenarios were evaluated each having a different number of depots of varying capacity and location within Kansas relative to a central commodity-receiving biorefinery to test GHG emissions uncertainty. The first scenario sited four preprocessing depots evenly across the state of Kansas but within the vicinity of counties having high biomass supply density. The second scenario located five depots based on the shortest depot-to-biorefinery rail distance and biomass availability. The logistics supply chain consists of corn stover harvest, collection and storage, feedstock transport from field to biomass preprocessing depot, preprocessing depot operations, and commodity transport from the biomass preprocessing depot to the biorefinery. Monte Carlo simulation was used to estimate the spatial uncertainty in the feedstock logistics gate-to-gate sequence. Within the logistics supply chain GHG emissions are most sensitive to the transport of the densified biomass, which introduces the highest variability (0.2–13 g CO2e/MJ) to life cycle GHG emissions. Moreover, depending upon the biomass availability and its spatial density and surrounding transportation infrastructure (road and rail), logistics can increase the variability in life cycle environmental impacts for lignocellulosic biofuels. Within Kansas, life cycle GHG emissions could range from 24 g CO2e/MJ to 41 g CO2e/MJ depending upon the location, size and number of preprocessing depots constructed. However, this range can be minimized through optimizing the siting of preprocessing depots where ample rail infrastructure exists to supply biomass commodity to a regional biorefinery supply system. [ABSTRACT FROM AUTHOR]

Aquaponics is often presented as a sustainable food production system that can reduce environmental costs of global food production; yet, its actual environmental effects are understudied. The aim of this research was to review the limited number of life cycle assessment studies dealing with aquaponics, and to highlight environmental cost and benefit of this practice. Our assessment highlights some of the problems, challenges, and advantages of aquaponics as a valuable food production system. We propose guidelines for future life cycle assessments of aquaponics that will facilitate policy and decision-making for farmers with respect to aquaponics. [ABSTRACT FROM AUTHOR]

Electric vehicles are being promoted worldwide in an attempt to mitigate greenhouse gas emissions and improve air-quality in cities. Yet, alternative propulsion systems could allow meeting climate change and air-quality policy goals while not raising other environmental burdens. This study offers a glimpse into the mobility solutions aside from traditional battery-electric vehicles (BEVs). A feasibility study of the novel combined electro-thermo-chemical (CETC) propulsion technology composed of a fuel-cell (FC), an internal-combustion engine (ICE) and thermochemical recuperation (TCR) of waste heat is performed based on a life-cycle assessment. A comprehensive comparison between the proposed technology and the BEV is conducted across multiple categories of environmental impacts from the stage of manufacturing, through vehicle use and vehicle end-of-life. Our findings showed for the first time that a technology comprising an internal combustion engine can assure a better environmental performance compared to BEV. Moreover, we demonstrate that the climate-change benefits of the suggested CETC technology over BEV are more pronounced when the share of renewable energy use increases. The study results show that the new CETC technology outperforms the battery electric propulsion for the majority of environmental impacts, including climate-change, air-pollution, human-health and ecological impacts by up to 22%, 62%, 60% and 43%, respectively. It is found that the environmental advantages of the CETC technology over the BEV stem mainly from the vehicle manufacturing stage, affected by the BEV's higher weight and resource-intensive production. These encouraging findings call for further examination and research into BEV alternatives, such as the discussed hybrid CETC powertrain. The latter has promising prospects for future implementation in both mobile and stationary applications. • We proved that a technology comprising ICE can assure a better environmental performance compared to BEV • Climate-change benefits of CETC technology over BEV are more pronounced when the share of a renewable energy use increases • CETC emits less GHG, less target pollutants and has lower ecological impacts than BEV • The overall energy demand from well-to-wheel is lower for the CETC-driven vehicle • CETC powertrain enables achieving higher power at the same efficiency than fuel cell [ABSTRACT FROM AUTHOR]

[Display omitted] • Promising corn-to-aviation fuel GHG emission LCA presented. • Pathway opportunity to meet sustainable aviation fuel policy targets. • CCS and agricultural best management needed to mitigate induced LUC. • Average fuel carbon intensity (AFCI) ranges from 5 to 36 gCO 2 e/MJ fuel. • Retrofitting 1st generation bio-refineries can benefit low C aviation fuel markets. This paper investigates options to produce low carbon and renewable aviation fuel through existing commercial first generation biorefineries, which could be strategic given the rapid growth of the electric vehicle market for personal mobility. We evaluate the environmental impact of retrofitting a first generation biorefinery to produce aviation fuel through chemical process simulation. The analysis investigates the potential for reducing greenhouse gas (GHG) emissions and displacing fossil fuel (petroleum-based jet kerosene) in the aviation fuel industry through using corn feedstocks in dry grind biorefineries to convert sugars to 1,4-dimethylcyclooctane (DMCO), which qualifies as renewable jet-A fuel blend and is infrastructure compatible. The average life cycle GHG emissions for a baseline case and a scenario with carbon capture and storage (CCS) of fermentative CO 2 are 36 and 5 g CO 2 e/MJ DMCO, respectively. Investment in CCS at the biorefinery and adoption of crop best management practices on farms are essential for mitigating the risks of induced land use change GHG emissions for existing corn biorefineries. DMCO as a low-carbon aviation fuel could be a strategic fuel product for retrofitting existing corn dry grind facilities. For aviation fuel supply, corn dry grind facilities could displace about 12 % of jet fuel demand in the near term, which would meet sustainable aviation fuel policy targets. We conclude that corn-to-DMCO shows promise for near-term low-carbon fuel markets in the aviation industry and as a bridge to developing biomass-based jet fuel in the future. [ABSTRACT FROM AUTHOR]