Life Cycle Assessments (LCAs) of thermoelectric plants frequently focus on impacts related to fuel and water consumption. The purpose of this research was to determine the environmental impact of the chemicals used for water conditioning in a Combined-Cycle Gas Turbine (CCGT) plant in Mexico. An LCA of the electricity generation process was carried out using the SimaPro software with the ReCiPe method, which includes 18 midpoint environmental impact categories. The process was broken down into stages, which were analyzed separately. To complete the study, an analysis of the fuel cycle and the materials used for maintenance works were included. Results showed that the most affected impact categories were water depletion (9.77 × 10⁻¹ m³/MWh), due mainly to the high volume of water consumption in the cooling systems and the reverse osmosis process; freshwater, marine, and terrestrial ecotoxicity (1.59 × 10⁻² kg 1,4 -DB eq/MWh), and human toxicity (1.1 × 10⁻¹ kg 1,4-DB eq/MWh)—due to the production and consumption of the chemicals used. One such chemical is hydrazine, which is a highly toxic compound to humans and other living organisms. It is worth mentioning that traces of some chemicals in wastewater discharges could be considered as emerging pollutants because of their potential health hazards, which have not been reported yet. Full article

In order to reduce vehicle emitted greenhouse gases (GHGs) on a global scale, the scope of consideration should be expanded to include the manufacturing, fuel extraction, refinement, power generation, and end-of-life phases of a vehicle, in addition to the actual operational phase. In this paper, the CO₂ emissions of conventional gasoline and diesel internal combustion engine vehicles (ICV) were compared with mainstream alternative powertrain technologies, namely battery electric vehicles (BEV), using life-cycle assessment (LCA). In most of the current studies, CO₂ emissions were calculated assuming that the region where the vehicles were used, the lifetime driving distance in that region and the CO₂ emission from the battery production were fixed. However, in this paper, the life cycle CO₂ emissions in each region were calculated taking into consideration the vehicle’s lifetime driving distance in each region and the deviations in CO₂ emissions for battery production. For this paper, the US, European Union (EU), Japan, China, and Australia were selected as the reference regions for vehicle operation. The calculated results showed that CO₂ emission from the assembly of BEV was larger than that of ICV due to the added CO₂ emissions from battery production. However, in regions where renewable energy sources and low CO₂ emitting forms of electric power generation are widely used, as vehicle lifetime driving distance increase, the total operating CO₂ emissions of BEV become less than that of ICV. But for BEV, the CO₂ emissions for replacing the battery with a new one should be added when the lifetime driving distance is over 160,000 km. Moreover, it was shown that the life cycle CO₂ emission of ICV was apt to be smaller than that of BEV when the CO₂ emissions for battery production were very large. Full article

Cement manufacturing is one of the most energy and CO₂ intensive industries. With the growth of cement production, CO₂ emissions are increasing rapidly too. Carbon capture and storage is the most feasible new technology option to reduce CO₂ emissions in the cement industry. More research on environmental impacts is required to provide the theoretical basis for the implementation of carbon capture and storage in cement production. In this paper, GaBi software and scenario analysis were employed to quantitatively analyze and compare the environmental impacts of cement production with and without carbon capture and storage technology, from the perspective of a life-cycle assessment; aiming to promote sustainable development of the cement industry. Results of two carbon capture and storage scenarios show decreases in the impacts of global warming potential and some environmental impacts. However, other scenarios show a significant increase in other environmental impacts. In particular, post-combustion carbon capture technology can bring a more pronounced increase in toxicity potential. Therefore, effective measures must be taken into account to reduce the impact of toxicity when carbon capture and storage is employed in cement production. CO₂ transport and storage account for only a small proportion of environmental impacts. For post-combustion carbon capture, most of the environmental impacts come from the unit of combined heat and power and carbon capture, with the background production of MonoEthanolAmine contributing significantly. In combined heat and power plants, natural gas is more advantageous than a 10% coal-saving, and thermal efficiency is a key parameter affecting the environmental impacts. Future research should focus on exploring cleaner and effective absorbents or seeking the alternative fuel in combined heat and power plants for post-combustion carbon capture. If the power industry is the first to deploy carbon capture and storage, oxy-combustion carbon capture is an excellent choice for the cement industry. Full article

The availability of resources is crucial for the socio-economic stability of our society. For more than two decades, there was a debate on how to structure this issue within the context of life-Cycle assessment (LCA). The classical approach with LCA is to describe “scarcity” for future generations (100–1000 years) in terms of absolute depletion. The problem, however, is that the long-term availability is simply not known (within a factor of 100–1000). Outside the LCA community, the short-term supply risks (10–30 years) were predicted, resulting in the list of critical raw materials (CRM) of the European Union (EU), and the British risk list. The methodology used, however, cannot easily be transposed and applied into LCA calculations. This paper presents a new approach to the issue of short-term material supply shortages, based on subsequent sudden price jumps, which can lead to socio-economic instability. The basic approach is that each resource is characterized by its own specific supply chain with its specific price volatility. The eco-costs of material scarcity are derived from the so-called value at risk (VAR), a well-known statistical risk indicator in the financial world. This paper provides a list of indicators for 42 metals. An advantage of the system is that it is directly related to business risks, and is relatively easy to understand. A disadvantage is that “statistics of the past” might not be replicated in the future (e.g., when changing from structural oversupply to overdemand, or vice versa, which appeared an issue for two companion metals over the last 30 years). Further research is recommended to improve the statistics. Full article

Desulphurization of oil-based fuels is common practice to mitigate the ecological burden to ecosystems and human health of SO_x emissions. In many countries, fuels for vehicles are restricted to 10 ppm sulphur. For marine fuels, low sulphur contents are under discussion. The environmental impact of desulphurization processes is, however, quite high: (1) The main current source for industrial hydrogen is Steam Methane Reforming (SMR), with a rather high level of CO₂ emissions, (2) the hydrotreating process, especially below 150 ppm, needs a lot of energy. These two issues lead to three research questions: (a) What is the overall net ecological benefit of the current desulphurization practice? (b) At which sulfphur ppm level in the fuel is the additional ecological burden of desulphurization higher than the additional ecological benefit of less SO_x pollution from combustion? (c) To what extent can cleaner hydrogen processes improve the ecological benefit of diesel desulphurization? In this paper we use LCA to analyze the processes of hydrotreatment, the recovery of sulphur via amine treating of H₂S, and three processes of hydrogen production: SMR without Carbon Capture and Sequestration (CCS), SMR with 53% and 90% CCS, and water electrolysis with two types of renewable energy. The prevention-based eco-costs system is used for the overall comparison of the ecological burden and the ecological benefit. The ReCiPe system was applied as well but appeared not suitable for such a comparison (other damage-based indicators cannot be applied either). The overall conclusion is that (1) the overall net ecological benefit of hydrogen-based Ultra Low Sulphur Diesel is dependent of local conditions, but is remarkably high, (2) desulphurization below 10 ppm is beneficial for big cities, and (3) cleaner production of hydrogen reduces eco-cost by a factor 1.8–3.4. Full article

To realize sustainable construction, planning for future maintenance costs is essential. In the case of multi-family housing, various maintenance issues can be expected to appear starting 10 years after completion. Therefore, preventive maintenance must be implemented in a systematic manner to cope with the problems caused by the natural aging of multi-family dwellings and to maintain a sustainable level of quality for the properties. In this study, maintenance costs were investigated for 224 multi-family housing units aged 20 years or older in Seoul, South Korea. Using Monte Carlo simulation in conjunction with expert interviews, a probabilistic maintenance cost analysis was conducted to analyze and estimate the variability in maintenance costs. The findings of the study propose that the use of probabilistic maintenance cost analysis can be developed into a useful planning tool for determining reasonable future maintenance costs in sustainable construction. Full article

This paper evaluates the eco-efficiency performance of agriculture at the sector level using the joint application of life cycle assessment (LCA) and data envelopment analysis (DEA) techniques. The research has been performed for the agricultural production of the 28 member states of the European Union (the EU-28). The foundation for the calculation of the eco-efficiency performance was a statistically selected set of impact categories derived from the life cycle impact assessment (LCIA) phase as input values and economic indicators, with the gross domestic product (GDP) of their agriculture as the output value. The results of the analysis showed that the agricultural sectors of 10 member states of the European Union (i.e., Belgium, Bulgaria, Estonia, Finland, Greece, Italy, Malta, the Netherlands, Romania, and Sweden) are relatively eco-efficient. The remaining 18 member states of the EU-28 have eco-inefficient agricultural sectors, though to a varying extent. This means that their agricultural sectors consume too many natural resources (in particular, energy), use too much fertilizer, and produce considerable amounts of airborne emissions in relation to the current level of GDP per hectare. These insights into the eco-efficiency performance of agriculture in the EU-28 may contribute to the adoption of better management techniques and more effective agricultural policies. Full article

In recent years, much research has been conducted internationally to quantitatively evaluate the environmental impact of buildings in order to reduce greenhouse gas emissions and address associated environmental problems. With this in mind, the Green Standard for Energy and Environmental Design (G-SEED) in South Korea was revised in 2016. However, the various possible evaluation methods make it difficult to conduct building life cycle assessment. Moreover, compared to research on residential buildings, life cycle assessment research on non-residential buildings is scarce. Therefore, this study analyzes primary building materials for life cycle assessment of current non-residential buildings to support Korean G-SEED requirements. Design documents for various non-residential buildings are obtained, and the types and numbers of materials used in production are determined. Next, the primary building materials contributing high cumulative weight based on the ISO14040 series of standards are analyzed. We then review the most commonly-used building materials while considering non-residential building types and structures. In addition, construction material reliability is evaluated using the environmental impact unit value. With our results, by suggesting the primary building materials in non-residential buildings, efficient life cycle assessment of non-residential buildings is possible in terms of time and cost. Full article

The concept of bioeconomy supports the diversification strategies of forest-based industries to create new value chains and contribute to economic growth and sustainability. The use of side streams or by-products of the pulp and paper industry (PPI) is seen as a promising approach. In line with this, the idea of substituting fossil-based materials and products is frequently discussed. One such example is the use of lignin as a bio-based alternative for fossil-based phenols. Lignin-based products not only have to fulfil identical technical requirements as their fossil-based counterparts, they are also expected to be more sustainable. This study conducts an integrated hotspot analysis of two lignin valorisation pathways during R&D. The analysis considers the provision of technical kraft lignin as a by-product of a state-of-the-art kraft pulp mill, followed by valorisation, either via solvent fractionation or via base-catalysed depolymerisation (BCD), and the final application of the valorised lignins in phenol formaldehyde resins. As a two-step approach, first of all, the environmental hotspots (e.g., energy-intensive process steps) along the valorisation pathways are identified. Secondly, a variation analysis is carried out, which involves the identification of sustainability levers (e.g., selection of solvents). Identifying those levers at an early research stage helps to support the R&D process towards sustainable product development. Full article

Industrial enzymes can be used to improve the digestibility of livestock feed components, thereby increasing the nutritional value of the feed, and allowing farmers to change and cost-optimize the feed composition. The purpose of this study was to investigate the environmental impacts of adding a starch-degrading enzyme (amylase) to feed for Brazilian chicken production. A lifecycle assessment covering all significant processes in the value chain as well as all significant impact categories was used as analytical tool. The application of amylase increases the energy value of corn in chicken feed and allows saving of costly fat in the feed. In Brazil, the saved fat is used either for biodiesel production or as a replacement for other fats in cleaning and hygiene products. The study showed that approximately 6% of greenhouse-gas emission from Brazilian chicken production could be avoided using the amylase. Using the amylase increases the contribution to nutrient enrichment by 0.6% when the excess fat is used for biodiesel. The use of amylase has little impact on agricultural land use, water consumption and acidification. Full article

Bio-plastics such as polylactic acid (PLA) have been investigated as a sustainable alternative to petroleum-based plastics. In this study, the carbon footprint of packaging films made from LDPE, PLA, and PLA/PBAT blends was measured with three different waste scenarios based on the database of South Korea using life cycle assessment (LCA). The LCA followed ISO standards, and was a cradle-to-grave analysis. The functional unit was defined as 400,000 pieces of a film of 300 × 250 mm with thickness of 0.06 mm for packaging bag manufacturing. The waste treatments considered were incineration, landfill, and recycling applied with the present conditions of South Korea. Under the present analysis conditions, the PLA film with landfill was the most effective for reducing carbon emission. The PLA/PBAT with incineration was the worst case among the packaging films tested. Incineration was the worst choice of waste treatment in terms of carbon dioxide emissions. Generally, landfill may not be the best option in terms of sustainability but landfill was a better option for waste treatment than incineration. In addition, before bio-plastics are blended with other material, the blending material should first be evaluated for its environmental impact. The blended bio-plastics with PLA, such as PLA/PBAT, can be more inimical to the environment in terms of carbon dioxide emissions than existing materials, such as LDPE. Full article

The emission of Greenhouse gases (GHG) during the life cycle of four hydropower stations with installed capacity from 95 MW to 500 MW are assessed by the integrated GHG reservoir tool developed by International Hydropower Association. Model inputs are extracted from multi-source geographic datasets and construction planning documents. Three main conclusions are summarized: (1) In pre- and post-impoundment stages, areal GHG emission balance in reservoir area depends on the climate background, humid subtropical regions are more active than arid temperate regions. In the construction stage, emissions from fill, concrete and equipment account for more than 70% of the total. (2) GHG intensity falls rapidly when lifetime increases from 10 to 40 years and then drops slightly when lifetime becomes longer, which is 13.60 tCO₂e/GWh for 50 years and 8.13 tCO₂e/GWh for 100 years on average. The emission rates of hydropower stations with lower installed capacity are obviously large if they work for less than 30 years and differ less with stations possessing a higher installed capacity when their lifetime approaches 100 years. (3) Comparing with electricity generated by coal in China whose GHG intensity is 822 tCO₂e/GWh, hydroelectricity is almost 100 times more efficient and clean. Thus, hydropower station plays an important role in dealing with the global warming issue as a substitution for a fossil fuel power source. Full article

Material efficiency is a key element of new thinking to address the challenges of reducing impacts on the environment and of resource scarcity, whilst at the same time meeting service and functionality demands on materials. Directly related to material efficiency is the concept of the Circular Economy, which is based on the principle of optimising the utility embodied in materials and products through the life-cycle. Although materials such as steel, on account of high recycling rates at end-of-life, are amongst the most ‘circular’ of manufactured materials, significant opportunities for greater material efficiency exist, which are yet to be widely implemented. Life Cycle Assessment (LCA) is commonly used to assess the environmental benefits of recovering and recycling materials through the manufacturing supply chain and at end-of-life. Using an example taken from renewable energy generation, this paper explores the correlation between product circularity and the environmental case for strategies designed to improve material efficiency. An LCA-based methodology for accounting for the recovery and reuse of materials from the supply chain and at end-of-life is used as the basis for calculating the carbon footprint benefits of five material efficiency scenarios. The results are compared with a number of proposed material circularity indicators. Two conclusions from this exercise are that (i) LCA methodologies based around end-of-life approaches are well placed for quantifying the environmental benefits of material efficiency and circular economy strategies and (ii) when applying indicators relating to the circularity of materials these should also be supported by LCA-based studies. Full article

Throughout its life-cycle, wood contributes to climate change mitigation through carbon storage and material and energy substitution. Focusing on wood use for piles, check dams, paved walkways, guardrails, and noise barriers, we quantified the nationwide potential for climate change mitigation in civil engineering in Japan through 2050. To assess mitigation potential, we examined life-cycle greenhouse gas (GHG) emissions that are avoided by storing carbon in wood and forests, substituting wooden materials for non-wooden materials (cement, concrete, steel, and asphalt), and substituting processing residue and waste wood salvaged from defunct civil engineering structures for fossil fuels (heavy oil). Our projections suggest that there will be a maximum potential domestic log volume of 6.80 million m³/year available for civil engineering use in Japan in 2050, and that it would be possible to produce this volume while increasing Japan’s forest resources over the long term. A maximum nationwide avoided GHG emissions potential of 9.63 million t-CO₂eq/year could be achieved in 2050, which is equivalent to 0.7% of Japan’s current GHG emissions. The breakdown of avoided emissions is 73%, 19%, and 8% for carbon storage, material substitution, and energy substitution, respectively, with the greatest contributions coming from carbon storage through the use of log piles. Full article

Life cycle assessment (LCA) is a key tool for determining environmental impacts for textiles and apparel and is the basis for the publicly available Higg Material Sustainability Index (MSI) developed by the Sustainable Apparel Coalition (SAC). This paper reviews and evaluates the Higg MSI with respect to rating of fabrics made from natural fibre types, with the aim of providing a constructive analysis of methodological issues identified by comparison with the International Standards and LCA guidelines. The major issues identified by the review were: (1) lack of sufficient guidance for comparative analysis and public disclosure; (2) incomplete system boundaries and the choice of functional unit; (3) the choice of attributional LCA methods and variable methods applied for handling multi-functionality; (4) use of generalised data and small datasets, without reported sensitivity or uncertainty; (5) exclusion of important impact categories, choice of LCIA methods and lack of coverage of non-LCA assessed issues; and (6) the choice of the weighting and normalisation approach. This review found that the provision of, and adherence to the appropriate standards and best practice in LCA would rectify most of these issues. To achieve the laudable aims of the Higg MSI, further development and refinement is needed to ensure robust information is provided to improve the sustainability of textiles. Full article

Aquaculture is the fastest growing food sector worldwide, mostly driven by a steadily increasing protein demand. In response to growing ecological concerns, life cycle assessment (LCA) emerged as a key environmental tool to measure the impacts of various production systems, including aquaculture. In this review, we focused on farmed salmonids to perform an in-depth analysis, investigating methodologies and comparing results of LCA studies of this finfish family in relation to species and production technologies. Identifying the environmental strengths and weaknesses of salmonid production technologies is central to ensure that industrial actors and policymakers make informed choices to take the production of this important marine livestock to a more sustainable path. Three critical aspects of salmonid LCAs were studied based on 24 articles and reports: (1) Methodological application, (2) construction of inventories, and (3) comparison of production technologies across studies. Our first assessment provides an overview and compares important methodological choices. The second analysis maps the main foreground and background data sources, as well as the state of process inclusion and exclusion. In the third section, a first attempt to compare life cycle impact assessment (LCIA) and feed conversion ratio (FCR) data across production technologies was conducted using a single factor statistical protocol. Overall, findings suggested a lack of methodological completeness and reporting in the literature and demonstrated that inventories suffered from incomplete description and partial disclosure. Our attempt to compare LCA results across studies was challenging due to confounding factors and poor data availability, but useful as a first step in highlighting the importance of production technology for salmonids. In groups where the data was robust enough for statistical comparison, both differences and mean equalities were identified, allowing ranking of technology clusters based on their average scores. We statistically demonstrated that sea-based systems outperform land-based technology in terms of energy demand and that sea-based systems have a generally higher FCR than land-based ones. Cross-study analytics also strongly suggest that open systems generate on average more eutrophying emissions than closed designs. We further discuss how to overcome bottlenecks currently hampering such LCA meta-analysis. Arguments are made in favor of further developing cross-study LCA analysis, particularly by increasing the number of salmonid LCA available (to improve sample sizes) and by reforming in-depth LCA practices to enable full reproducibility and greater access to inventory data. Full article