Trends in greenhouse gas emissions from consumption and production of animal food products – implications for long-term climate targets

To analyse trends in greenhouse gas (GHG) emissions from production and consumption of animal products in Sweden, life cycle emissions were calculated for the average production of pork, chicken meat, beef, dairy and eggs in 1990 and 2005. The calculated average emissions were used together with food consumption statistics and literature data on imported products to estimate trends in per capita emissions from animal food consumption. Total life cycle emissions from the Swedish livestock production were around 8.5 Mt carbon dioxide equivalents (CO₂e) in 1990 and emissions decreased to 7.3 Mt CO₂e in 2005 (14% reduction). Around two-thirds of the emission cut was explained by more efficient production (less GHG emission per product unit) and one-third was due to a reduced animal production. The average GHG emissions per product unit until the farm-gate were reduced by 20% for dairy, 15% for pork and 23% for chicken meat, unchanged for eggs and increased by 10% for beef. A larger share of the average beef was produced from suckler cows in cow–calf systems in 2005 due to the decreasing dairy cow herd, which explains the increased emissions for the average beef in 2005. The overall emission cuts from the livestock sector were a result of several measures taken in farm production, for example increased milk yield per cow, lowered use of synthetic nitrogen fertilisers in grasslands, reduced losses of ammonia from manure and a switch to biofuels for heating in chicken houses. In contrast to production, total GHG emissions from the Swedish consumption of animal products increased by around 22% between 1990 and 2005. This was explained by strong growth in meat consumption based mainly on imports, where growth in beef consumption especially was responsible for most emission increase over the 15-year period. Swedish GHG emissions caused by consumption of animal products reached around 1.1 t CO₂e per capita in 2005. The emission cuts necessary for meeting a global temperature-increase target of 2° might imply a severe constraint on the long-term global consumption of animal food. Due to the relatively limited potential for reducing food-related emissions by higher productivity and technological means, structural changes in food consumption towards less emission-intensive food might be required for meeting the 2° target.     

Life cycle assessment of light-emitting diode downlight luminaire—a case study

Purpose

Light-emitting diode (LED) technology is increasingly being used for general lighting. Thus, it is timely to study the environmental impacts of LED products. No life cycle assessments (LCA) of recessed LED downlight luminaires exist in the literature, and only a few assessments of any type of LED light source (component, lamp and luminaire) are available.

Methods

The LCA of a recessed LED downlight luminaire was conducted by using the data from the luminaire manufacturer, laboratory measurements, industry experts and literature. The assessment was conducted using SimaPro LCA software. EcoInvent and European Reference Life Cycle Database were used as the databases. The LCA included a range of environmental impacts in order to obtain a broad overview. The functional unit of the LCA was one luminaire used for 50,000 h. In addition, the sensitivity of the environmental impacts to the life was studied by assessing the LED downlight luminaire of 36,000 h and 15,000 h useful life and to the used energy sources by calculating the environmental impacts using two average energy mixes: French and European.

Results and discussion

The environmental impacts of the LED luminaire were mostly dominated by the energy consumption of the use. However, manufacturing caused approximately 23 % of the environmental impacts, on average. The environmental impacts of manufacturing were mainly due to the driver, LED array and aluminium parts. The installation, transport and end of life had nearly no effect on the total life cycle impacts, except for the end of life in hazardous waste. The life cycle environmental impacts were found to be sensitive to the life of the luminaire. The change from the French to the European average energy mix in use resulted to an even clearer dominance of the use stage.

Conclusions

The case study showed that the environmental impacts of the LED downlight luminaire were dominated by the use-stage energy consumption, especially in the case of the European energy mix in use. Luminous efficacy is, thus, a relatively appropriate environmental indicator of the luminaire. As LED technology possesses generally higher luminous efficacy compared to conventional ones, the LED luminaire is considered to represent an environmentally friendly lighting technology. However, data gaps exist in the data in LED product manufacturing and its environmental impacts. The environmental impacts of different LED products need to be analysed in order to be able to precisely compare the LED technology to the conventional lighting technologies.     

Life cycle assessment of composite packaging waste management—a Chinese case study on aseptic packaging

Purpose

Approximately 46,000 t/day of packaging waste was generated in China in 2010, of which, 2,500 t was composite packaging waste. Due to the lack of recycling technology and an imperfect recovery system, most of this waste is processed in sanitary landfills. An effective packaging waste management system is needed since this waste not only uses up valuable resources, but also increases environmental pollution. The purpose of this study is to estimate the environmental impact of the treatment scenarios in composite packaging waste which are commonly used in China, to determine the optimum composite packaging waste management strategy, and to design new separating and recycling technology for composite packaging, based on the life cycle assessment (LCA) results.

Methods

To identify the best treatment for composite packaging waste, the LCA software SimaPro 7.1.6 was used to assist in the analysis of the environmental impacts, coupled with the impact assessment method Eco-Indicator 99. LCA for composite packaging waste management was carried out by estimating the environmental impacts of the four scenarios most often used in China: landfill, incineration, paper recycling, and separation of polyethylene and aluminum. One ton of post-consumption Tetra Pak waste was selected as the functional unit. The data on the mass, energy fluxes, and environmental emissions were obtained from literature and site investigations.

Results and discussion

Landfill—scenario 1—was the worst waste management option. Paper recycling—scenario 3—was more environmentally friendly than incineration, scenario 2. Scenario 4, separating out polyethylene and aluminum, was established based on the LCA result, and inventory data were obtained from the demonstration project built by this research. In scenario 4, the demonstration project for the separation of polyethylene and aluminum was built based on the optimum conditions from single-factor and orthogonal experiments. Adding this flow process into the life cycle of composite packaging waste treatment decreased the environmental impacts significantly.

Conclusions

The research results can provide useful scientific information for policymakers in China to make decisions regarding composite packaging waste. Incineration could reduce more environmental impacts in the respiratory inorganics category, and separation of polyethylene and aluminum, in the fossil fuel category. If energy saving is the primary governmental goal, the separation of polyethylene and aluminum would be the better choice, while incineration would be the better choice for emission reduction.     

The methodology and results of using life cycle assessment to measure and reduce the greenhouse gas emissions footprint of “Major Events” at the University of Arizona

Purpose

In 2012 and 2013, the University of Arizona’s Office of Sustainability conducted environmental life cycle assessments of two Homecoming events that drew 60,000 attendees each. Based on reviews of published literature, this is the first time that a process-based life cycle assessment has been conducted for an event of this size. This study contributes to the small but growing field of research using life cycle assessment to track the environmental impacts of events.

Methods

The assessments at The University of Arizona considered the environmental impact of food, materials, waste, travel, and lodging. The effects of these components of Homecoming weekend were evaluated in terms of nine different categories. However, this paper focuses on greenhouse gas emissions. The data collection process for these assessments was completed by student observers and supplemented with information provided by university departments, event organizers, and survey responses from attendees. Data were analyzed using SimaPro Life Cycle Assessment software and using data from the EcoInvent database. Based on the results of the 2012 study, initiatives were put into place for 2013 that were designed to reduce the environmental impact of the subsequent Homecoming event.

Results and discussion

The results show that the total impact of Homecoming 2012 was an estimated 2400 metric tons of CO₂-eq, whereas the impact of Homecoming 2013 was an estimated 1900 metric tons of CO₂-eq, a 19 % decrease year over year. Data were analyzed in terms of carbon dioxide emissions in both years. Travel made up the majority of the environmental impact (82.04 % in 2012 and 77.77 % in 2013), followed by accommodations (17.5 % in 2012 and 19.31 % in 2013), with energy, materials, and food having almost negligible impacts (0.46 % in 2012 and 2.92 % in 2013). While there had been noticeable changes in the measured impact of food and energy between 2012 and 2013, the significant impact of travel overshadowed all other impact categories in terms of greenhouse gas emissions, making these changes less noticeable. Analysis of each of these categories of impact helped to establish best practices for mitigating the impact of events on a category-by-category basis.

Conclusions

This study introduces a framework for assessing impacts of a large university event while also highlighting ways to reduce impacts. The initiatives implemented in 2013 to reduce impacts of large-scale events can be informative to others working to reduce emissions at large events. Additional recommendations to reduce impacts of large events are provided.

     

Capability of social life cycle assessment for analyzing the artisanal small-scale gold mining sector—case study in the Amazonian rainforest in Brazil

The International Journal of Life Cycle Assessment - Gold extraction in the Amazonian rainforest is accompanied by ecological threats and social grievances, but at the same time, the artisanal...     

The influence of substratum age on patterns of protozoan assemblages in freshwater Aufwuchs — a case study

The sulfate reduction rate was measured for almost four years in the profundal sediments of Lake Kizaki, a mesotrophic lake in central Japan. The rate was generally highest in the surface layer and decreased with depth. Seasonally, sulfate reduction tended to be high in spring and summer, and then to decrease until the end of stratification (December) in spite of a constant in situ temperature of around 6 °C, although fluctuations were found in every year. The rate also fluctuated greatly according to year. The maximum rate of sulfate reduction was 0.33 mmol m⁻² d⁻¹ in May, 1990, and the minimum was 0.004 mmol m⁻² d⁻¹ in March, 1993. These relatively low rates, compared with those reported for freshwater sediments, seem to be due to low concentrations of sulfate in the sediments (5–23 μmol l⁻¹ in the surface layer). The rate was highly correlated with the concentration of sulfate in the sediments. The addition of sulfate stimulated sulfate reduction in all sediment samples tested, but adding lactate did not. Therefore, sulfate reduction should be limited mainly by the supply of sulfate. Measurements of sulfate reduction rates at different concentrations of added sulfate revealed a low concentration of half-saturation constant as low as 12 μmol l⁻¹.     

A novel social life cycle assessment method for determining workers’ human development: a case study of the sugarcane biorefineries in Brazil

The International Journal of Life Cycle Assessment - The social life cycle assessment (S-LCA) methodology needs to advance in its methodological development, mainly regarding the impact assessment...     

Comparative life cycle assessment of car disc brake systems—case study results and method discussion about comparative LCAs

Purpose

Two life cycle assessment (LCA) studies comparing a new low-particulate-matter-emission disc brake and a reference disc brake were presented. The purpose was to identify the difference in potential environmental impacts due to a material change in the new disc brake parts. Additionally, the validity was investigated for the simplification method of omitting identical parts in comparative LCA. This was done by comparing the results between the simplified and the full LCA model.

Methods

The two disc brakes, new disc brake and reference disc brake, were assessed according to the LCA ISO standards. The ReCiPe 2016 Midpoint (hierarchist) impact assessment method was chosen. Simplifying a comparative LCA is possible, all identical parts can be omitted, and only the ones that differ need to be assessed. In this paper, this simplification was called comparative LCA with an omission of identical parts.

Results and discussion

The comparative impacts were analysed over seventeen impact categories. The new disc brake alternative used more resources during the manufacture of one disc compared to the reference disc brake alternative. The shorter life length of the reference disc demanded a higher number of spare part discs to fulfil the same functional unit, but this impact was reduced due to material recycling. The new disc brake impacts were connected primarily to the coating and secondly to the pad manufacture and materials. The validity of the simplification method was investigated by comparing the results of the two LCA models. The impact differences were identical independent of the LCA model, and the same significant impact categories could be identified. Hence, the purpose of the study could be fulfilled, and the simplification was valid.

Conclusions

Both LCA models, simplified and full, revealed that the new disc brake had limited environmental advantages. The omission of identical parts made it more challenging to determine if an impact was significant or insignificant. The simplification seemed to be reasonable.

     

A study of spatial and temporal variability in the adenine nucleotides of lake phytoplankton during a diel cycle (Lac Pavin — France)

A study of diel variations in the adenine nucleotide concentrations of natural phytoplanktonic populations led to the following conclusions:There are significant diel variations in cellular ATP concentrations. However, this temporal variability is not as great as the spatial variability between the various sampling depths, characterized by different phytoplankton populations. Within a globally stable pool of adenine nucleotides, diel variations inside the algal cell mainly take place at the expense of ATP and AMP, while ADP concentrations remain relatively stable.The statistical relationship between algal biomass obtained from cell counts and from adenine nucleotides also confirms maximum stability for ADP and (ATP + ADP + AMP). The diel variations in adenine nucleotide cell concentrations gradually become smaller with depth. This probably reflects the importance of light in causing such variability.     

Inter-annual variability in the environmental performance of viticulture technical management routes—a case study in the Middle Loire Valley (France)

Purpose

Improving the environmental performances of viticulture practices is particularly complicated during unfavorable climatic conditions because of the need for fungal and other pest pressure and the variability of phytosanitary control methods available for winegrowers. However, winegrowers wish to improve the environmental performances of their practices regardless of climatic conditions. The objective of the study was to quantify the variability in environmental impacts due to climatic variations, and changes in viticulture practices induced by climatic variability.

Methods

Life cycle assessment was used to evaluate the environmental impacts of viticulture technical management routes (TMR) implemented on five plots in the Loire Valley for the Chenin Blanc grape variety. These TMRs are representative of the range of practices used in the region, including intensive conventional practices to moderate organic practices. The study covered two different years of production (2011 and 2013) under contrasting climatic conditions. The first year (2011) was hot and dry, which are favorable conditions for viticulture, while the second year (2013) was cold and humid, which are unfavorable conditions.

Results and discussion

During the unfavorable year, the number of phytosanitary treatments and soil maintenance interventions increased for most of the studied TMRs. This meant that the inter-annual variability in environmental impact was significant, depending on the type of TMR, with differences in impacts ranging from 19% to more than 40% between 2011 and 2013. Managing environmental impacts was found to be more difficult for the organic systems when climatic conditions are unfavorable (in 2013). The non-organic TMRs showed less variation in environmental impacts than the organic TMRs between the 2 years studied.

Conclusions

This study shows the importance of taking into account inter-annual variability in environmental assessments of viticulture systems. Indeed, winegrowers do not respond the same way to climate variability mainly with regard to plant protection and soil maintenance. Viticulture is very sensitive to inter-annual climate variations due to the parasitic pressure variability. The different production systems do not give to winegrowers the same possibilities for adapting practices to limit their impact on the environment.

     

Robustness of life table methods in large populations—a study by computer simulation

The robustness of the product life table estimator of the survival function was studied for large populations under perturbations in the age distribution, changing levels of mortality and changing patterns of fertility. A macrosimulation system, based on a class of stochastic population models called generalised age-dependent branching processes, was used to carry out the numerical investigations. Aside from drastic perturbations in the age distribution and changes in levels of mortality, the product life table estimator of the survival function was found to be robust in large populations, under a variety of conditions.     

An analytical framework for social life cycle impact assessment—part 2: case study of labor impacts in an IC packaging company

Purpose

The pressure on brand firms in the electronics industry to improve the labor conditions of their workers in their global production networks is increasing. Given the significance of mitigating the impacts of production on labor, this study used the new development method of social life cycle impact assessment (SLCIA) for conducting labor impact assessment. An illustrative example in an integrated circuit (IC) packaging company is presented to demonstrate the assessment of the impacts and the identification of the potential for improvement of labor practices among three factories.

Methods

SLCIA method was proposed based on the UNEP/SETAC Guidelines that were reviewed in our previous work, Part 1 (in a previous article): Methodology. The proposed method was used to assess the impacts of operations on labor in the three factories of an IC packaging company. Nineteen indicators of labor–stakeholders were used to collect data from factories and organizations in 2012. The obtained values from these three factories were translated into social impact scores that ranged from 1 to 5. The score of each indicator was multiplied by the weights of each indicator, and a final score of labor situations was generated to identify the hotspots of labor impacts and to identify the factory with better labor performance.

Results and discussion

The main goal of this study is to demonstrate the effectiveness of our proposed SLCIA method in assessing the labor impacts in the electronics industry. Among three factories of IC packaging, factory C was ranked as having the lowest social impact on labor with a higher performance, followed by factories B and A. In addition, the results show that four indicators, “lacking labor union,” “did not hire a sufficient number of disabled employees,” “overtime work that exceeded the legal limit,” and “excessive number of dispatched workers,” were recognized as the main social impacts on labor in IC packaging production.

Conclusions

The SLCA technique was used to assess the impacts of the production processes of three IC packaging factories on the labor conditions of their factory workers. The proposed method shed light on the significant impacts of such processes. The proposed model demonstrated its potential advantage by systematically and effectively identifying the labor impact hotspots, which could assist managers in devising strategies that could improve the labor situations within their organizations.

     

Life cycle inventory and impact assessment for an asphalt pavement road construction—a case study in Brazil

The International Journal of Life Cycle Assessment - Currently, there are no life cycle impact data available on the construction of road infrastructure in Brazil. This study aimed to determine...     

In search of expression bottlenecks in recombinant CHO cell lines—a case study

The efficient production of recombinant proteins such as antibodies typically involves the screening of an extravagant number of clones in order to finally select a stable and high-producing cell line. Thereby, the underlying principles of a powerful protein machinery, but also potential expression limitations, often remain poorly understood. To shed more light on this topic, we applied several different techniques to investigate a previously generated cell line (4B3-IgA), which expressed recombinant immunoglobulin A (IgA) with an unusually low specific productivity. Results were compared to the host cell line and to another recombinant CHO cell line (3D6-IgA) expressing another IgA that binds to an overlapping epitope. The low specific productivity of clone 4B3-IgA could not be explained by GCN or mRNA levels, but insufficiencies in protein maturation and/or secretion were determined. Despite the presence of free light chain polypeptides, they occasionally failed to associate with their heavy chain partners. Consequently, heavy chains were misassembled and accumulated to form intracellular aggregates, so-called Russell bodies. These protein deposits evoked the expression of increased amounts of ER-resident chaperones to combat the induced stress. Despite bottlenecks in protein processing, the cells’ quality checkpoints remained intact, and predominantly correctly processed IgA was exported into the culture medium. The results of our study demonstrated that recombinant protein expression was impaired by heavy chain aggregation despite the presence of a disposable light chain and revealed elevated chaperone formation in combination with limited antibody assembly. Our studies suggest that the primary amino acid sequence and consequently the resulting structure of an expressed protein need to be considered as a factor influencing a cell’s productivity.     

A holomorph approach to xiphosuran evolution—a case study on the ontogeny of Euproops

Specimens of Euproops sp. (Xiphosura, Chelicerata) from the Carboniferous Piesberg quarry near Osnabrück, Germany, represent a relatively complete growth series of 10 stages. Based on this growth sequence, morphological changes throughout the ontogeny can be identified. The major change affects the shape of the epimera of the opisthosoma. In earlier stages, they appear very spine-like, whereas in later stages the bases of these spine-like structures become broader; the broadened bases are then successively drawn out distally. In the most mature stage known, the epimera are of trapezoidal shape and approach each other closely to form a complete flange around the thoracetron (=fused tergites of the opisthosoma). These ontogenetic changes question the taxonomic status of different species of Euproops, as the latter appear to correspond to different stages of the ontogenetic series reconstructed from the Piesberg specimens. This means that supposed separate species could, in fact, represent different growth stages of a single species. It could alternatively indicate that heterochrony (=evolutionary change of developmental timing) plays an important role in the evolution of Xiphosura. We propose a holomorph approach, i.e., reconstructing ontogenetic sequences for fossil and extant species as a sound basis for a taxonomic, phylogenetic, and evolutionary discussion of Xiphosura.     

Physical parameter-based allocation for the energy consumption of pyro-metallurgical system—a case study on nickel production in China

Purpose

The objectives of this study were to establish an allocation model for the energy consumption of pyro-metallurgical system based on the physical relationship between the input and output, apply the established model to nickel production in China and compare the difference between the allocation results derived from the established model and the traditional models.

Methods

The basic methodological idea of this study is that the energy input of a multi-output pyro-metallurgical process should be allocated according to how the energy input is consumed in the process. The energy consumption of pyro-metallurgical system was decomposed into different categories (e.g. energy absorption of chemical reaction and energy loss), and these categories were classified into two groups, i.e. the categories of energy consumption dependent on the product ratio (PRDE) and the categories of energy consumption independent on the product ratio (PRIE); then, the allocation basis for each category of energy consumption was determined through the physical relationship between the energy input and metal output. The allocation for the energy consumption of nickel production in China was carried out; the system boundary includes two sub-systems (i.e. Ni–Cu coproduction system and Ni refining system), and the energy consumption of the coproduction system should be allocated; the basic data required by the allocation model and the compilation of LCI were mainly obtained from literature.

Results and discussion

The energy consumption of the processes of mining, drying, converting and floating-grinding belongs to PRIE following the principle of mass-based allocation, and the corresponding allocation factors are 64, 64, 69 and 69 %, respectively. The categories of energy consumption involved in the smelting process (the key process for demonstrating the allocation model) include both PRIE and PRDE, and the aggregated allocation factor was calculated as 56 %. The allocation result derived from the established model is lower than the results derived from the mass-based model and the market value-based model, because that, through the desulphurization reactions that occurred in the smelting process, the chemical states of copper and nickel are transformed from copper pyrite (CuFeS₂) and nicopyrite ((Fe,Ni)₉S₈) into cuprous sulphide (Cu₂S) and nickel sulphide (Ni₃S₂), and copper compound releases more sulphur atoms than nickel compound. When analyzing a single pyro-metallurgical process, the result of allocation is sensitive to basis selection; however, when comparing two or more pyro-metallurgical processes, the comparison result of allocation is relatively insensitive to basis selection.

Conclusions

The energy input of pyro-metallurgical system is consumed in different physical-chemical ways; the decomposition of energy consumption is significant for choosing allocation bases; the basis of mass can only be used for the allocation of PRIE, and choosing the same allocation basis for different cases without a systematic analysis will be inappropriate. The requirement of some nontraditional extra inventory data is the major limitation of the established model. This study mainly focused on how nickel production system consumes the energy input, and the energy consumption patterns of other production systems should be taken into account in future studies.

     

Land use planning in Ireland—a life cycle energy analysis of recent residential development in the Greater Dublin Area

Background, aim, and scope  One third of the total housing stock in the Republic of Ireland has been built in 10 years up to and including 2006 and of this approximately 34% was built in the Greater Dublin Area (GDA). Much of the housing was low-density with poor public transport links leading to doubts over its sustainability—particularly in terms of energy use. Although the country is committed to reducing greenhouse gas emissions to 13% above 1990 levels by the period 2008–2012, by 2005, emissions were already 25.4% higher than the baseline and current projections are that this figure will rise to 37% over the period. The residential sector is estimated to contribute to approximately 24.5% of energy-related CO₂ emissions. This paper estimates total emissions from residential developments in the GDA constructed between 1997 and 2006. Materials and methods  Carbon dioxide equivalent (CO₂) emissions are estimated using a life cycle assessment approach over a 100-year building lifespan and employing process, input–output and hybrid energy techniques. Life cycle stages include: construction, operation, transport, maintenance and demolition. The main data sources include: national population and industry census data, household travel survey data, residential energy performance surveys and national accounts. The GDA was split into four zones each encompassing development at increasing radii from Dublin’s city centre, namely: city centre, suburbs, exurbs and commuter towns. Results  Per capita CO₂ life cycle emissions in the GDA were found to be approximately 50–55% greater in the exurbs and commuter towns than in the city centre. Of the five life cycle stages studied, operational energy requirements (predominantly space heating and hot water, but including power) contributed most significantly to emissions (68%), followed by transport (17%), construction (9%) and maintenance/renovation (6%). Discussion  Operating emissions from dwellings in the commuter town and extra-urban zones were almost twice those in the city centre both due to larger dwelling sizes and the predominance of detached and semi-detached dwellings (with large amounts of exposed walls) in the former and the prevalence of smaller apartments in the latter. Car use was most pronounced in the zones furthest from the city centre where per capita emissions were almost twice those of residents in the city centre. Despite their smaller size, the per capita construction CO₂ emissions of apartments were approximately one third greater than for low-rise dwellings due to the greater energy intensity of the structure. However, this difference was more than compensated for by the significantly lower operational emissions referred to above. Conclusions  In 2006, recurrent CO₂ emissions (operational, transport and maintenance) from dwellings built in the GDA over the ten preceding years were 2,108 kt while construction-related emissions in that year were 1,325 kt giving a total contribution from the residential sector of 3,434 kt CO₂/annum—representing 4.9% of national emissions for that year. Had the development policy prescribed ‘city centre’-type development and transport modes, then emissions for the year 2006 would have been 2,892 kt CO₂—a reduction of almost 16% over the actual figure. However, in this scenario recurrent emissions would have been reduced to 1,417 kt CO₂—a reduction of 33% over actual levels. Recommendations and perspectives  This study supports Irish and international governments’ policies aimed at curbing CO₂ emissions from the domestic sector which focus primarily on reducing operational emissions from new and existing housing through design and construction improvements. However, it demonstrates that significant reductions in operational emissions are associated with high-density residential development with modest floor areas. Furthermore, it highlights the scope for transport emissions’ reductions through better spatial planning leading to reduced car travel.