Environmental performance of building materials: life cycle assessment of a typical Sicilian marble

Background, aim, and scope  

The building sector is strategically important for achieving sustainability. Therefore, the improvement of energy and environmental performances are relevant targets because precious building materials such as marble have a significant impact on the environment. The aim of this paper is an analysis of a typical Sicilian marble (Perlato di Sicilia) to evaluate its energy and environmental performance. Marble plays an important role in the economy of Italy and has a global market share of 58% in terms of exports. For the main production areas of marble, relevant environmental performance data are missing except for one region (Tuscany—Massa e Carrara province). Perlato di Sicilia, the main marble of Custonaci (Sicily), has never been analyzed previously.     

Integrating environmental and economic life cycle analysis in product development: a material selection case study

Purpose

Achieving sustainability by rethinking products, services and strategies is an enormous challenge currently laid upon the economic sector, in which materials selection plays a critical role. In this context, the present work describes an environmental and economic life cycle analysis of a structural product, comparing two possible material alternatives. The product chosen is a storage tank, presently manufactured in stainless steel (SST) or in a glass fibre reinforced polymer composite (CST). The overall goal of the study is to identify environmental and economic strong and weak points related to the life cycle of the two material alternatives. The consequential win–win or trade-off situations will be identified via a life cycle assessment/life cycle costing (LCA/LCC) integrated model.

Methods

The LCA/LCC integrated model used consists in applying the LCA methodology to the product system, incorporating, in parallel, its results into the LCC study, namely those of the life cycle inventory and the life cycle impact assessment.

Results and discussion

In both the SST and CST systems, the most significant life cycle phase is the raw materials production, in which the most significant environmental burdens correspond to the Fossil fuels and Respiratory inorganics categories. The LCA/LCC integrated analysis shows that the CST has globally a preferable environmental and economic profile, as its impacts are lower than those of the SST in all life cycle stages. Both the internal and external costs are lower, the former resulting mainly from the composite material being significantly less expensive than stainless steel. This therefore represents a full win–win situation. As a consequence, the study clearly indicates that using a thermoset composite material to manufacture storage tanks is environmentally and economically desirable. However, it was also evident that the environmental performance of the CST could be improved by altering its end-of-life stage.

Conclusions

The results of the present work provide enlightening insights into the synergies between the environmental and the economic performance of a structural product made with alternative materials. Furthermore, they provide conclusive evidence to support the integration of environmental and economic life cycle analysis in the product development processes of a manufacturing company or, in some cases, even in its procurement practices.     

Social life cycle assessment of palm oil biodiesel: a case study in Jambi Province of Indonesia

Purpose

This study aims to investigate the social implications of palm oil biodiesel via a case study using a life cycle assessment framework.

Methods

The case study was conducted in Jambi Province of Indonesia and involved several stakeholders, such as value chain actors, employees, local community members, government, and nongovernmental organization representatives related in palm oil industry. The assessment was carried out using social criteria developed by adopting the Society of Environmental Toxicology and Chemistry/United Nations Environment Programme Code of Practice, supplemented by an expert survey, and supported by literature review. Stakeholders’ perspectives were evaluated by determining the gaps between expected and perceived quality of each social criterion, which are gauged using seven-point Likert scale.

Results and discussion

Twenty-four social criteria were developed and aggregated into five social impact categories: human rights, working condition, cultural heritage, social–economic repercussion, and governance. These criteria have been weighted, useful for further application in multicriteria decision analysis. The results of the stakeholders’ survey reveal the critical social hotspots, which are the issues within the impact categories of working conditions and cultural heritage.

Conclusions

In order to achieve the social equitability of palm oil biodiesel, which is an important pillar to sustainability, efforts must be put to address these social hotspots through actions in various policy level.     

Functional unit influence on building life cycle assessment

Purpose

The building sector is one of the most relevant sectors in terms of environmental impact. Different functional units (FUs) can be used in life cycle assessment (LCA) studies for a variety of purposes. This paper aimed to present different FUs used in the LCA of buildings and evaluate the influence of FU choice and setting in comparative studies.

Methods

As an example, we compared the “cradle to grave” environmental performance of four typical Brazilian residential buildings with different construction typologies, i.e., multi-dwelling and single dwelling, each with high and basic standards. We chose three types of FU for comparison: a dwelling with defined lifetime and occupancy parameters, an area of 1 m² of dwelling over a year period, and the accommodation of an occupant person of the dwelling over a day.

Results and discussion

The FU choice was found to bias the results considerably. As expected, the largest global warming indicator (GWi) values per dwelling unit and occupant were identified for the high standard dwellings. However, when measured per square meter, lower standard dwellings presented the largest GWi values. This was caused by the greater concentration of people per square meter in smaller area dwellings, resulting in larger water and energy consumption per square meter. The sensitivity analysis of FU variables such as lifetime and occupancy showed the GWi contribution of the infrastructure more relevant compared with the operation in high and basic standard dwellings. The definition of lifetime and occupancy parameters is key to avoid bias and to reduce uncertainty of the results when performing a comparison of dwelling environmental performances.

Conclusions

This paper highlights the need for adequate choice and setting of FU to support intended decision-making in LCA studies of the building sector. The use of at least two FUs presented a broader picture of building performance, helping to guide effective environmental optimization efforts from different approaches and levels of analysis. Information regarding space, time, and service dimensions should be either included in the FU setting or provided in the building LCA study to allow adjustment of the results for subsequent comparison.

     

Environmental life cycle assessment of a commercial office building in Thailand

Background, aim, and scope  To minimize the environmental impacts of construction and simultaneously move closer to sustainable development in the society, the life cycle assessment of buildings is essential. This article provides an environmental life cycle assessment (LCA) of a typical commercial office building in Thailand. Almost all commercial office buildings in Thailand follow a similar structural, envelope pattern as well as usage patterns. Likewise, almost every office building in Thailand operates on electricity, which is obtained from the national grid which limits variability. Therefore, the results of the single case study building are representative of commercial office buildings in Thailand. Target audiences are architects, building construction managers and environmental policy makers who are interested in the environmental impact of buildings. Materials and methods  In this work, a combination of input–output and process analysis was used in assessing the potential environmental impact associated with the system under study according to the ISO14040 methodology. The study covered the whole life cycle including material production, construction, occupation, maintenance, demolition, and disposal. The inventory data was simulated in an LCA model and the environmental impacts for each stage computed. Three environmental impact categories considered relevant to the Thailand context were evaluated, namely, global warming potential, acidification potential, and photo-oxidant formation potential. A 50-year service time was assumed for the building. Results  The results obtained showed that steel and concrete are the most significant materials both in terms of quantities used, and also for their associated environmental impacts at the manufacturing stage. They accounted for 24% and 47% of the global warming potential, respectively. In addition, of the total photo-oxidant formation potential, they accounted for approximately 41% and 30%; and, of the total acidification potential, 37% and 42%, respectively. Analysis also revealed that the life cycle environmental impacts of commercial buildings are dominated by the operation stage, which accounted for approximately 52% of the total global warming potential, about 66% of the total acidification potential, and about 71% of the total photo-oxidant formation potential, respectively. The results indicate that the principal contributor to the impact categories during the operation phase were emissions related to fossil fuel combustion, particularly for electricity production. Discussion  The life cycle environmental impacts of commercial buildings are dominated by the operation stage, especially electricity consumption. Significant reductions in the environmental impacts of buildings at this stage can be achieved through reducing their operating energy. The results obtained show that increasing the indoor set-point temperature of the building by 2°C, as well as the practice of load shedding, reduces the environmental burdens of buildings at the operation stage. On a national scale, the implementation of these simple no-cost energy conservation measures have the potential to achieve estimated reductions of 10.2% global warming potential, 5.3% acidification potential, and 0.21% photo-oxidant formation potential per year, respectively, in emissions from the power generation sector. Overall, the measures could reduce approximately 4% per year from the projected global warming potential of 211.51 Tg for the economy of Thailand. Conclusions  Operation phase has the highest energy and environmental impacts, followed by the manufacturing phase. At the operation phase, significant reductions in the energy consumption and environmental impacts can be achieved through the implementation of simple no-cost energy conservation as well as energy efficiency strategies. No-cost energy conservation policies, which minimize energy consumption in commercial buildings, should be encouraged in combination with already existing energy efficiency measures of the government. Recommendations and perspectives  In the long run, the environmental impacts of buildings will need to be addressed. Incorporation of environmental life cycle assessment into the current building code is proposed. It is difficult to conduct a full and rigorous life cycle assessment of an office building. A building consists of many materials and components. This study made an effort to access reliable data on all the life cycle stages considered. Nevertheless, there were a number of assumptions made in the study due to the unavailability of adequate data. In order for life cycle modeling to fulfill its potential, there is a need for detailed data on specific building systems and components in Thailand. This will enable designers to construct and customize LCAs during the design phase to enable the evaluation of performance and material tradeoffs across life cycles without the excessive burden of compiling an inventory. Further studies with more detailed, reliable, and Thailand-specific inventories for building materials are recommended.     

Opportunities and challenges of implementing life cycle assessment in seafood certification: a case study for Spain

Purpose

Eco-labelling has become part of the business strategy of companies thanks to numerous advantages in terms of engaging with consumers and gaining market quota. The aim of this article is to present a critical discussion on the development and implementation of a new eco-label named pescaenverde, registered in Spain, as the first type III eco-label in the Spanish fishing sector that is based on life cycle approaches for seafood products.

Methods

More specifically, it aims to complement ecosystem-based eco-labels with the computation of the carbon footprint and the energy return on investment (EROI) of seafood products. Furthermore, it proposes to discuss the ecological criteria, certification process or the opportunities and challenges of the market implementation of this eco-label in detail. Finally, the authors argue that life cycle eco-labels should be considered important complements for more specific sector- or ecosystem-oriented labels already in use, rather than direct competitors.

Results and discussion

There has been much criticism towards the eco-labelling sector as regards the transparency and scientific rigour of its standards. The fishing and seafood sector, which has experienced a boom in eco-labelling in recent years, due mainly to the strength of the Marine Stewardship Council certification scheme, is not alien to this controversy, since critics advocate expanding the concept of sustainable fisheries beyond an ecosystem approach in order to account for global environmental concerns such as greenhouse gas (GHG) emissions or energy use. Not surprisingly, the European Union and other authorities currently encourage eco-labels to base their ecological criteria on life cycle approaches. Therefore, the current study discusses the ecological criteria, certification process or the opportunities and challenges of the market implementation of this eco-label in detail.

Conclusions

The specificity of the life cycle inventory scheme used in pescaenverde delivers an accurate computation of environmental impacts for the specific case of Spanish fisheries. However, the geographical expansion of this scheme to other nations or regions will be conditioned by an important software adaptation to the particular inventory characteristics of the new fisheries, fleets and products.

Recommendations

Adapting ecological criteria to other situations would also need substantial discussion, since the use of this certification scheme is not intended to contrast or compare seafood products against each other but to provide consumers with an easily identifiable label through which they can detect environmentally sustainable practices in terms of GHG emissions and energy use in the fishing fleets supporting the seafood products purchased.

     

Subcategory assessment method for social life cycle assessment: a case study of high-density polyethylene production in Alberta,Canada

Purpose

The aim of this study is to develop and test the applicability of a new subcategory assessment method (SAM) for social life cycle assessment using a case study on high-density polyethylene (HDPE) production by Dow Chemical Canada facility in Alberta, Canada.

Methods

The methodology is characterized by six steps: (1) definition of the goal and scope of the assessment; (2) life cycle inventory data collection including context data at country level and company-specific data for foreground processes; (3) impact assessment where the subcategories’ results for foreground processes at company level are evaluated using a new SAM developed and the country social performance in the different subcategories is evaluated using some assessment intervals; (4) comparing the social performance of foreground processes to the social background context in sector or country; (5) evaluating the social performance of background processes using sector performance evaluation from Product Social Impact Life Cycle Assessment (PSILCA) database or country performance evaluation conducted in the study; (6) and discussion and conclusion.

Results and discussion

The method developed was able to identify the subcategories that need high level or some level of improvements along the cradle-to-gate life cycle of HDPE. In addition, the stakeholders with high negative effect were highlighted in every life cycle stage. Through this approach, Dow Chemical Canada is able to prioritize its actions and focus on the areas where its performance is still low compared to its peers in the sector or compared to the situation in the country. Moreover, through using PSILCA database or country performance evaluation to investigate the social performance of background processes, Dow Chemical Canada can determine the social hotspots areas that need more focus from its suppliers.

Conclusions

Applying the new subcategory assessment approach proposed in this study provides an objective way to assess the subcategories while differentiating between two levels of assessment: (1) the commitment to the social subcategory in the company’s policy (defined as cutoff requirement) and (2) the evidence of good/bad practices of the subcategory. In addition, the comparison of performance of the companies in foreground processes to the social background in sector or country has improved the objectivity further.

     

Comparing technologies for municipal solid waste management using life cycle assessment methodology: a Belgian case study

Purpose

The present study aims at identifying the best practice in residual municipal solid waste management using specific data from Liège, a highly industrialized and densely populated region of Belgium. We also illustrate the importance of assumptions relative to energy through sensitivity analyses and checking uncertainties regarding the results using a Monte Carlo analysis.

Methods

We consider four distinct household waste management scenarios. A life cycle assessment is made for each of them using the ReCiPe method. The first scenario is sanitary landfill, which is considered as the base case. In the second scenario, the refuse-derived fuel fraction is incinerated and a sanitary landfill is used for the remaining shredded organic and inert waste only. The third scenario consists in incinerating the whole fraction of municipal solid waste. In the fourth scenario, the biodegradable fraction is collected and the remaining waste is incinerated. The extracted biodegradable fraction is then treated in an anaerobic digestion plant.

Results and discussion

The present study shows that various scenarios have significantly different environmental impact. Compared to sanitary landfill, scenario 4 has a highly reduced environmental impact in terms of climate change and particulate matter formation. An environmental gain, equal to 10, 37, or 1.3 times the impact of scenario 1 is obtained for, respectively, human toxicity, mineral depletion, and fossil fuel depletion categories. These environmental gains are due to energetic valorization via the incineration and anaerobic digestion. Considering specific categories, greenhouse gas emissions are reduced by 17 % in scenario 2 and by 46 % in scenarios 3 and 4. For the particulate matter formation category, a 71 % reduction is achieved by scenario 3. The figures are slightly modified by the Monte Carlo analysis but the ranking of the scenarios is left unchanged.

Conclusions

The present study shows that replacing a sanitary landfill by efficient incineration significantly reduces both emissions of pollutants and energy depletion, thanks to electricity recovery.     

Integrating cost-benefits analysis and life cycle assessment of green roofs: a case study in Florida

Abstract

Multiple environmental benefits can be achieved by using a green roof instead of conventional roofs. To better understand the LCA and cost-effectiveness of a green roof, a case study was performed. Two energy models, one with conventional white roof and the other with green roof, were created using eQUEST software to compare the influence of green roof on building energy consumption. The results indicated that the application of a green roof reduced annual space heating and cooling electricity consumption by 9500 kWh (2.2 kWh per square meter). The LCA shows that by using an extensive green roof in lieu of a conventional white roof the LCA measures at the product, construction, and end-of-life stages increased due to the use of additional layers. However, these increases are offset by the reduction of LCA measures at the use stage such that the overall environmental impacts of green roof is less than that of conventional roof. To find out the cost-effectiveness of green roof, a 50-year cost-benefits analysis was conducted. The analysis showed that the net savings of the green roof is negative compared to the white roof it replaced due to its higher initial cost and follow on maintenance cost.     

An accumulative model for the comparative life cycle assessment case study: iron and steel process

Life cycle assessment is a powerful tool in the evaluation of the environmental performance. However, there is no generally accepted methodology. To develop a practical method, an accumulative model for the comparative life cycle assessment is established and applied in the two typical iron and steel processes, the DRI/EF process and the BF/BOF process. The results indicate that the method could quantitatively compare the alternatives. When the DRI/EF process is compared with the BF/BOF process, it is shown that the IREI (integrated relative environmental index) is 60.22% for the production of iron and 52.4% for the production of steel, respectively. The environmental performance of the DRI/EF process is superior to that of the BF/BOF process.     

The assessment of the relevance of building components and life phases for the environmental profile of nearly zero-energy buildings: life cycle assessment of a multifamily building in Italy

Purpose

Since the construction sector is a considerable energy consumer and greenhouse gas (GHG) producer, the EU rules strive to build nearly zero-energy buildings, by reducing the operative energy and yearning for on-site energy production. This article underlines the necessity to go beyond the energy evaluations and move towards the environmental assessment in a life cycle perspective, by comparing the impacts due to building materials and energy production devices.

Methods

We compared the operational energy impacts and those of technologies and materials carrying out a life cycle assessment (LCA; ISO 14040, ISO 14044, EN 15643–2, EN 15978) on a nearly zero-energy building (ZEB), a residential complex with 61 apartments in four buildings, situated near Milan (Italy). We consider all life cycle phases, including production, transport, building site activities, use and maintenance; the materials inventory was filled out collecting data from invoices paid, building site reports, construction drawings and product data sheets. To make the assessment results comparable, we set a functional unit of 1 m² of net floor area in 1 year (1 m²y), upon a lifespan of 100 years. The environmental data were acquired from Ecoinvent 2.2.

Results and discussion

The results highlight the important role of the pre-use and maintenance phases in building life so that in a nearly ZEB, the environmental impacts linked to the use are no longer the major proportion: the pre-use phase accounts for 56 %, while the operative energy is only 31 % of the total. For this reason, if the environmental assessment of the case study was shrunk to the operational consumption, only one third of the impacts would be considered. The consumption of non-renewable resources after 100 years are 193,950 GJ (133.5 kWh/m²y); the GHG emissions are 15,300 t (37.8 kg of CO₂?eq/m²y). In the pre-use phase, structures have the major impacts (50 %) and the load of system components is unexpectedly high (12 %) due to the ambition of on-site energy production.

Conclusions

Paying attention to the operative energy consumption seems to address to only one third of the environmental impacts of buildings: the adoption of LCA as a tool to guide the design choices could help to identify the solution which ensures the lowest overall impact on the whole life, balancing the options of reducing the energy requirements, the on-site production from renewable sources and the limitation of the impacts due to building components (simpler and more durable).

     

Dynamic life cycle assessment: framework and application to an institutional building

Purpose

This paper uses a dynamic life cycle assessment (DLCA) approach and illustrates the potential importance of the method using a simplified case study of an institutional building. Previous life cycle assessment (LCA) studies have consistently found that energy consumption in the use phase of a building is dominant in most environmental impact categories. Due to the long life span of buildings and potential for changes in usage patterns over time, a shift toward DLCA has been suggested.

Methods

We define DLCA as an approach to LCA which explicitly incorporates dynamic process modeling in the context of temporal and spatial variations in the surrounding industrial and environmental systems. A simplified mathematical model is used to incorporate dynamic information from the case study building, temporally explicit sources of life cycle inventory data and temporally explicit life cycle impact assessment characterization factors, where available. The DLCA model was evaluated for the historical and projected future environmental impacts of an existing institutional building, with additional scenario development for sensitivity and uncertainty analysis of future impacts.

Results and discussion

Results showed that overall life cycle impacts varied greatly in some categories when compared to static LCA results, generated from the temporal perspective of either the building's initial construction or its recent renovation. From the initial construction perspective, impacts in categories related to criteria air pollutants were reduced by more than 50 % when compared to a static LCA, even though nonrenewable energy use increased by 15 %. Pollution controls were a major reason for these reductions. In the future scenario analysis, the baseline DLCA scenario showed a decrease in all impact categories compared with the static LCA. The outer bounds of the sensitivity analysis varied from slightly higher to strongly lower than the static results, indicating the general robustness of the decline across the scenarios.

Conclusions

These findings support the use of dynamic modeling in life cycle assessment to increase the relevance of results. In some cases, decision making related to building design and operations may be affected by considering the interaction of temporally explicit information in multiple steps of the LCA. The DLCA results suggest that in some cases, changes during a building's lifetime can influence the LCA results to a greater degree than the material and construction phases. Adapting LCA to a more dynamic approach may increase the usefulness of the method in assessing the performance of buildings and other complex systems in the built environment.     

Consequential life cycle assessment: a review

Purpose  

Over the past two decades, consequential life cycle assessment (CLCA) has emerged as a modeling approach for capturing environmental impacts of product systems beyond physical relationships accounted for in attributional LCA (ALCA). Put simply, CLCA represents the convergence of LCA and economic modeling approaches.     

Social life cycle assessment of average Irish dairy farm

Purpose

The majority of sustainability studies of dairy farms focused on environmental performance and profitability; however, social aspect has been hardly assessed. This study aims to investigate the social impacts of dairy farm via a case study using a social life cycle assessment framework.

Methods

The assessment was carried out applying the social LCA Guideline by UNEP-SETAC. Nineteen suitable social indicators were selected from four stakeholder categories of the guideline. Characterization and normalization were further developed based on data availability. National farm survey data was used as foreground data for farm activities, supplemented with background data from public database and life cycle working environment (LCWE) data by Gabi database. All indicators were divided into three groups: functional unit-related quantitative indicators, non-functional unit-related quantitative indicators and semi-quantitative indicators.

Results and discussion

Irish dairy farming has positive social impacts on value chain actors and society, predominantly positive impacts for local community and generally positive values for workers. The main negative impacts are health and safety issue, equal opportunity for workers, and safe and healthy living conditions for the local community. Possible actions to improve the social performance include introducing more efficient and robotic milk production systems; applying better handling methods and using real time decision support to operational management for emissions reduction.

Conclusions

This study is the first attempt of social LCA in Ireland. It demonstrated a possible method to carry out SLCA for Irish dairy sector. The results identified the positive and negative social hotspot of dairy farm with recommendation for future improvement.

     

Life cycle inventories and life cycle assessment for an electricity grid network: case study of the Jamali grid,Indonesia

The International Journal of Life Cycle Assessment - The electricity and heat sectors are reported to contribute approximately 40% of total CO2 emissions from the energy sector in Indonesia....     

A life cycle assessment case study of ground rubber production from scrap tires

Purpose

The number of scrap tires generated in China has grown dramatically every year. Generation of ground rubber from scrap tires is the dominant management option in China. It is necessary to assess the environmental impacts of ground rubber production from scrap tires to provide technical advices on a cleaner production.

Methods

Production of ground rubber from recycled scrap tires consist of three steps: rubber powder preparation, devulcanization, and refining. A process life cycle assessment (LCA) of ground rubber production from scrap tires is carried out, and Eco-indicator 99 method coupled with ecoinvent database is applied to evaluate the environmental impacts of this process.

Results and discussion

During the ground rubber production stage, the impact factor of respiratory inorganic is the most serious one. Devulcanization has the highest environmental load of about 66.2 %. Moreover, improvement on the flue gas treatment contributes to a cleaner production and a more environmental-friendly process. Applying clean energy can largely reduce environmental load by about 21.5 %.

Conclusions

The results can be a guidance to reduce environmental load when producing ground rubber from scrap tires. Meanwhile, increasing energy efficiency, improving environmental protection equipment, and applying clean energy are the effective measures to achieve this goal.