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PurposeThe main purpose of this article is to assess the environmental impacts associated with the fishing operations related to European anchovy fishing in Cantabria (northern Spain) under a life cycle approach.
MethodsThe life cycle assessment (LCA) methodology was applied for this case study including construction, maintenance, use, and end of life of the vessels. The functional unit used was 1 kg of landed round anchovy at port. Inventory data were collected for the main inputs and outputs of 32 vessels, representing a majority of vessels in the fleet.
Results and discussionResults indicated, in a similar line to what is reported in the literature, that the production, transportation, and use of diesel were the main environmental hot spots in conventional impact categories. Moreover, in this case, the production and transportation of seine nets was also relevant. Impacts linked to greenhouse gas (GHG) emissions suggest that emissions were in the upper range for fishing species captured with seine nets and the value of global warming potential (GWP) was 1.44 kg CO2 eq per functional unit. The ecotoxicity impacts were mainly due to the emissions of antifouling substances to the ocean. Regarding fishery-specific categories, many were discarded given the lack of detailed stock assessments for this fishery. Hence, only the biotic resource use category was computed, demonstrating that the ecosystems’ effort to sustain the fishery is relatively low.
ConclusionsThe use of the LCA methodology allowed identifying the main environmental hot spots of the purse seining fleet targeting European anchovy in Cantabria. Individualized results per port or per vessel suggested that there are significant differences in GHG emissions between groups. In addition, fuel use is high when compared to similar fisheries. Therefore, research needs to be undertaken to identify why fuel use is so high, particularly if it is related to biomass and fisheries management or if skipper decisions could play a role.
PurposeParticleboard is a composite panel comprising small pieces of wood bonded by adhesives. The particleboard industry is growing in Pakistan, but there is little information on the environmental impacts associated with this product. Therefore, the aim of this study was to develop a life cycle assessment of particleboard manufactured in Pakistan and to provide suggestions to improve its environmental profile. The study covers energy use and associated environmental impacts of raw materials and processes during particleboard manufacture in the year 2015–2016.
MethodsThe study uses a cradle-to-gate (distribution center) life cycle assessment approach. The reference unit for this study was 1.0 m3 of finished, uncoated particleboard. Primary data from the particleboard mill surveys were combined with secondary database information and modeled using CML 2000 v.2.05 methodology and a cumulative exergy demand indicator present in the SimaPro v.8.3 software.
Results and discussionThe results reveal that urea formaldehyde resin, transportation of raw materials, and finished product distribution had the highest contribution to all the environmental impact categories evaluated. Heavy fuel oil and natural gas consumption was responsible for abiotic depletion, photochemical oxidation, ozone layer depletion, and marine aquatic ecotoxicity impacts. The rotary dryer and hot press were the most important sectors in terms of emissions from the manufacturing process. The total cumulative exergy demand required for manufacturing of 1.0 m3 particleboard was 15,632 MJ-eq, with most of the energy usage associated with non-renewable, fossil fuel sources. A sensitivity analysis was conducted for a reduction in the quantity of urea formaldehyde resin consumed and freight transport distances.
ConclusionsThe results indicated that reducing the urea formaldehyde resin use and freight distances could greatly decrease environmental impacts. Most of the surveyed mills did not have emissions control systems, and most of the mills exceed the limits set by the National Environmental Quality Standards of Pakistan. Environmental impact improvements might be attained by reducing quantity of urea formaldehyde resin and transportation freight distances and by installing pollution control devices.
PurposeWe extend a life cycle assessment (LCA) embracing both economic and social perspectives to develop an integrated solid waste management system for Kuwait. This study considers the domestic waste generated by households and waste generated commercially. Six municipal solid waste (MSW) scenarios (SR1, SR2, …, SR6) are evaluated using a triple bottom line (TBL) approach that incorporates environmental, financial, and social bottom lines (social BLs).
MethodsWithin the TBL framework, the environmental BL employs LCA in accordance with ISO 14044. The financial BL is calculated using capital and operational costs as well as the associated recycling revenues. The social BL applies macro-economic indicators that examine the effects of a given MSW scenario (SR) on the inhabitants. To integrate the TBLs, we apply an analytic hierarchy process (AHP) because of its advantage of pairwise unit-free rescaling. The relative importance of each BL is determined by considering the political, legal, socio-cultural, and economic climates of the country. The relative weights are cross-multiplied with indicators from each BL to calculate a composite sustainability index (CSI) for the proposed MSW SR.
Results and discussionThe environmental BL (LCA) indicates that global warming, acidification, and human toxicity are the most adversely affected impact categories, considering the local conditions and waste composition. Environmentally, SR1 (landfilling) scored the worst in almost all impact categories and, thus, was labeled the worst-case scenario environmentally. SR6 (composting, recycling, and incineration) performed the best from an environmental perspective. Financially, landfilling (SR1) is the most economical scenario. Any SR that focused on incineration (SR2 and SR5) was financially unfavorable. The scenarios that involved composting were scored as financially reasonable (SR3, SR4, and SR6). From a social acceptability perspective, SR2 (incineration) scored the highest, while SR1 (landfills) scored the lowest. Finally, across the TBL framework, SR4 (composting and incineration) had the highest CSI based on the relative importance scheme adopted for each BL.
ConclusionsAlthough they are often overlooked in most LCA studies, the financial and social aspects are indispensable to proving feasibility and credibility at a strategic level. The complexity of financial and social formulations in LCA is inherited from the difficulty in quantifying emissions and other impacts. In addition, from a social perspective, the contingent risks and associated uncertainty vary widely across cultures, ideologies, and degrees of development and are further complicated because of the scarcity and uncertainty of the data.
PurposeIn a context of flourishing eco-labelling programs and environment policy for food products, LCA application to agricultural systems faces the challenges of being operational, accurate and exhaustive. This is particularly challenging for the newly developing LCA and ISO-compliant water footprinting, with many LCIA methods only recently developed, but no dedicated inventory method. To support the inventory of elementary water flows, LCA practitioners have a variety of tools available, ranging from databases (e.g. World Food LCA Database) to complex agro-hydrological models. To allow all LCA practitioners to fulfil their diverse agri-food LCA objectives, a review of available inventory tools for field water flows and recommendations are needed.
MethodsThe selection of the appropriate method and tool for the inventory of field water flows in agri-food LCA studies depends on the objectives of the LCA study, data and resources available (time and skills). We analysed water inventory and agri-food LCA databases by evaluating the models on which they rely and their input data. Then, we explored the use of agro-hydrological models for LCA aiming at discriminating between different cropping system practices (LCA-based eco-design).
Results and discussionWater inventory and agri-food LCA databases provide estimates of theoretical water consumed by a crop and rely on data and methods that have limitations, making them suitable only for background agricultural LCAs. In addition, databases do not support the application of water availability footprint indicators (assessing quantitative water use and water quality alteration). For the LCA-based eco-design of cropping systems, the inventory of water flows should be based on a model simulating evapotranspiration, deep percolation and runoff accounting for crop specificities, pedo-climatic conditions and agricultural management. In particular, the model should account for possible water, salinity and nutrient stresses; assess evaporation and transpiration separately; and estimate runoff and drainage according to the system specificities. Yield should not be estimated with a model but with primary data. Recommended and default data sources are provided for each input parameter.
ConclusionsThe FAO AquaCrop model represents a good trade-off between accuracy, simplicity and robustness for LCA-based eco-design of cropping systems. However, this model is not yet applicable for perennial crops. Beyond a single model selection, this is a modelling approach that we characterised in this work.
PurposeRenewable energies are promoted in order to reduce greenhouse gas emissions and the depletion of fossil fuels. However, plants for renewable electricity production incorporate specifically higher amounts of materials being rated as potentially scarce. Therefore, it is in question which (mineral) resources contribute to the overall resource consumption and which of the manifold impact assessment methods can be recommended to cover an accurate and complete investigation of resource use for renewable energy technologies.
MethodsLife cycle assessment is conducted for different renewable electricity production technologies (wind, photovoltaics, and biomass) under German conditions and compared to fossil electricity generation from a coal-fired power plant. Focus is given on mineral resource depletion for these technologies. As no consensus has been reached so far as to which impact assessment method is recommended, different established as well as recently developed impact assessment methods (CML, ReCiPe, Swiss Ecoscarcity, and economic scarcity potential (ESP)) are compared. The contribution of mineral resources to the overall resource depletion as well as potential scarcity are identified.
Results and discussionOverall resource depletion of electricity generation technologies tends to be dominated by fossil fuel depletion; therefore, most renewable technologies reduce the overall resource depletion compared to a coal-fired power plant. But, in comparison to fossil electricity generation from coal, mineral resource depletion is increased by wind and solar power. The investigated methods rate different materials as major contributors to mineral resource depletion, such as gallium used in photovoltaic plants (Swiss Ecoscarcity), gold and copper incorporated in electrical circuits and in cables (CML and ReCiPe), and nickel (Swiss Ecoscarcity and ReCiPe) and chromium (ESP) for stainless steel production. However, some methods lack characterization factors for potentially important materials.
ConclusionsIf mineral resource use is investigated for technologies using a wider spectrum of potentially scarce minerals, practitioners need to choose the impact assessment method carefully according to their scope and check if all important materials are covered. Further research is needed for an overall assessment of different resource compartments.
PurposeGold is one of the most significant metals in the world, with use in various sectors including the electronic, health, and fashion industries. The Philippines has the world’s third largest known Au deposits and is ranked 20th in global gold production. Of the country’s annual production, about 80% is from the small-scale gold mining (SSGM) sector. This work estimates the first location-specific life cycle energy use and CO2 emissions of SSGM establishments in the Philippines.
MethodsProcess-based LCA was used with functional unit of 100 g Au and observed data from 2010 to 2011 for mining, comminution, recovery, and refining. Four gold production paths were observed in the provinces of Benguet and Camarines Norte, namely, amalgamation, cyanidation with carbon-in-leach (CIL), cyanidation with leaching with zinc, and combination of amalgamation and cyanidation with CIL.
Results and discussionIt was estimated that 3–18 g of Au was extracted for every ton of ore within 57–159 man-hours from mining to refining. Energy use estimates ranged from 3501 to 67,325 MJ/100 g Au, while CO2 emission estimates ranged from 398 to 5340 kg CO2/100 g Au. The combination of amalgamation and cyanidation with CIL processes was the least energy and carbon intensive, while cyanidation with CIL process was the most intensive. Electricity use accounted for 95–100% of total emissions, except in cyanidation with CIL where kerosene accounts for 77% of the total. Since SSGMs contributed 80% of the 40 tons of Au produced in the Philippines in 2014, the SSGM energy use was estimated to be between 1120 and 21,544 TJ and the CO2 emissions to be between 129 and 1726 ktons CO2. Energy estimates are most sensitive to refining process yield and electrical equipment efficiency.
ConclusionsThe estimated life cycle emissions rate for SSGM in the Philippines is lower than available estimates of large-scale mining. Notwithstanding, given the sector’s reliance on fossil fuels for its energy needs and the Philippines’ pledge to reduce its CO2 footprint by 70% in 2030, every effort to mitigate energy use and CO2 emission counts. Three main recommendations toward energy consumption and CO2 emissions reduction in SSGMs are proposed: (1) policy to promote technologies that are energy-efficient and processes that maximize gold process yield, (2) effective Minahang Bayan (SSGM mining zone mandated by law) implementation to ensure use of higher-grade ores, and (3) adoption of renewable energy in Minahang Bayans to promote energy independence and mitigate CO2 emissions.
PurposeSeveral efforts have attempted to incorporate the sources of uncertainty and variability into the life cycle assessment (LCA) of pavements. However, no method has been proposed that can simultaneously consider data quality, methodological choices, and variability in inputs and outputs without the need for complementary software. This study aims to develop and implement a flexible method that can be used in the LCA software to assess the effects of these sources on the conclusions.
MethodsA Monte Carlo analysis was conducted and applied in a comparative LCA of pavements to assess the preferred scenario. The uncertainty of the results was first estimated by considering the data quality using the ecoinvent database. Moreover, the variabilities of the materials, construction methods, and repair stages of the pavement life cycle were included in the analysis by assigning continuous uniform probability distributions to each variable. Ultimately, the probability of methodological choices was modeled using uniform distributions and assigning a portion of the area of the distribution to each scenario. The individual and combined effects of these uncertainty and variability sources were assessed in a comparative LCA of asphalt and concrete pavements in a cold region such as Quebec (Canada).
Results and discussionThe results of the Monte Carlo analysis show that the allocation choices can change the environmentally preferred scenario in four midpoint categories. These categories are significantly dominated by the crude oil supply chain. The variability in construction materials and methods can change the preferred scenario in the damage categories, namely, human health and global warming. Additionally, parameter uncertainty has a significant effect on the conclusion of the preferred scenario in ecosystem quality. The worst qualitative scores are given to the geographical uncertainty of the elementary flow that primarily contributes to this category (i.e., zinc). The simultaneous effect of the uncertainty and variability sources prevents the decision-maker from reaching a less uncertain conclusion about ecosystem quality, human health, and global warming effects.
ConclusionsThis study demonstrates that it is feasible to assess the cumulative effects of common uncertainty and variability sources using commercial LCA software, including Monte Carlo simulation. Based on the variability and uncertainty of the results, the identification of a certain conclusion is case specific at both the midpoint and endpoint levels. Increasing the quality of the inventory is one solution to decreasing the uncertainties related to human health, ecosystem quality, and global warming regarding pavement LCA. This improvement can be achieved by avoiding the adaptation of a similar process to match the considered process and using practical construction efficiencies and realistic construction materials. The effectiveness of these tasks must be assessed in future studies. It should be noted that these conclusions were determined regardless of the uncertainty in the characterization factors of the impact assessment method.
PurposeDiminishing fossil resources and environmental concerns associated with their vast utilization have been in focus by energy policy makers and researchers. Among the different scenarios put forth to commercialize biofuels, various biorefinery concepts have aroused global interests because of their ability in converting biomass into a spectrum of marketable products and bioenergies. This study was aimed at developing different novel castor-based biorefinery scenarios for generating biodiesel and other co-products, i.e., ethanol and biogas. In these scenarios, glycerin, heat, and electricity were also considered as byproducts. Developed scenarios were also compared with a fossil reference system delivering the same amount of energy through the combustion of neat diesel.
Materials and methodsLife cycle assessment (LCA) was used to investigate the environmental consequences of castor biodiesel production and consumption with a biorefinery approach. All the input and output flows from the cultivation stage to the combustion in diesel engines as well as changes in soil organic carbon (SOC) were taken into account. Impact 2002+ method was used to quantify the environmental consequences.
Results and discussionThe LCA results demonstrated that in comparison with the fossil reference system, only one scenario (i.e., Sc-3 with co-production of significant amounts of biodiesel and biomethane) had 16% lower GHG emissions without even considering the improving effect of SOC. Moreover, resource damage category of this scenario was 50% lower than that of neat diesel combustion. The results proved that from a life cycle perspective, energy should be given priority in biorefineries because it is essential for a biorefinery to have a positive energy balance in order to be considered as a sustainable source of energy. Despite a positive effect on energy and GHG balances, these biorefineries had negative environmental impacts on the other damage categories like Human Health and Ecosystem Quality.
ConclusionsAlthough biorefineries offer unique features as promising solutions for mitigating climate change and reducing dependence on fossil fuels, the selection of biomass processing options and management decisions can affect the final results in terms of environmental evaluations and energy balance. Moreover, if biorefineries are focused on transportation fuel production, a great deal of effort should still be made to have better environmental performance in Human Health and Ecosystem Quality damage categories. This study highly recommends that future studies focus towards biomass processing options and process optimization to guarantee the future of the most sustainable biofuels.
PurposeLife cycle assessment aims to assess trade-offs between different impacts, including mineral and fossil resource use. The goals of this study were (1) to derive surplus cost potentials (SCPs) for a large number of fossil and mineral resources and (2) to derive surplus costs per megawatt hour of electricity produced for a range of both renewable and non-renewable technologies.
MethodsThe SCP of a resource refers to the total cost increase over the full amount of resource expected to be extracted in the future, expressed as US dollar (USD) per unit of resource extracted. For the fossil resources oil, natural gas and hard coal, cost-cumulative production relationships were derived that were subsequently used as input to calculate SCPs for these three fossil resources. For mineral resources, SCPs were readily available for 12 resources and platinum-group metals as a separate group. SCPs for an additional number of 57 mineral resources and 4 mineral resource groups were derived on the basis of a statistical relationship between SCP and average price in year 2013. The SCPs of fossil and mineral resources were subsequently used to derive the surplus costs per megawatt hour of 10 electricity production technologies.
Results and discussionThe surplus costs of electricity production ranged from 0.3 to 148 USD2013/MWh. The three fossil-based energy production technologies, based on coal, gas and oil, resulted in the highest overall surplus costs (23 to 148 USD2013/MWh), while nuclear, geothermal, photovoltaic, wind and hydropower technologies have the lowest surplus costs (0.3–6 USD2013/MWh). We found that the contribution of fossil resource use to the surplus costs was higher compared to mineral resource use, including the renewable energy technologies.
ConclusionsSurplus costs of fossil and mineral resources can be used to compare renewable and non-renewable electricity production technologies. This case study shows that fossil fuel use drives the surplus costs of all energy technologies.
PurposeCurrently, the reduction of weight in automotive is a very important topic in order to lower the air pollution. In this context, the purpose of the present paper was to analyze a real case study through a comparison of the environmental sustainability between a conventional steel crossbeam for light commercial vehicles and an innovative lightweight aluminum one.
MethodsFor both scenarios, a cradle-to-grave life cycle assessment methodology and a sensitivity analysis has been used through the study of the following phases: mineral extraction, component manufacturing, use on vehicle, and end of life. In particular, many primary data and a complete vehicle model simulation with three different European driving cycles have been used in order to reach the highest possible level of accuracy during the analysis.
Results and discussionRegarding the manufacturing phase, the aluminum component’s production gave the highest impact because of the high energy required in the mineral reduction. Anyway, this stage of the analysis had a low effect on the entire LCA, because the benefit of weight reduction during vehicle use showed a strongly higher contribution. The urban driving cycle had the most relevant impact, as a consequence of the frequent start and stop operations and the longest time with engine at idle speed, while the extra-urban cycle is the less demanding due to its higher average speed and no start and stop.
ConclusionsIn conclusion, the present research demonstrated the environmental importance of the lightweight for an actual case study in the commercial vehicles field.