Carles M. Gasol

Environmental analysis of rainwater harvesting infrastructures in diffuse and compact urban models of Mediterranean climate

PurposeAt present, many urban areas in Mediterranean climates are coping with water scarcity, facing a growing water demand and a limited conventional water supply. Urban design and planning has so far largely neglected the benefits of rainwater harvesting (RWH) in the context of a sustainable management of this resource. Therefore, the purpose of this study was to identify the most environmentally friendly strategy for rainwater utilization in Mediterranean urban environments of different densities.Materials and methodsThe RWH systems modeled integrate the necessary infrastructures for harvesting and using rainwater in newly constructed residential areas. Eight scenarios were defined in terms of diffuse (D) and compact (C) urban models and the tank locations ((1) underground tank, (2) below-roof tank, (3) distributed-over-roof tank, and (4) block tank). The structural and hydraulic sizing of the catchment, storage, and distribution subsystems was taken into account using an average Mediterranean rainfall, the area of the harvesting surfaces, and a constant water demand for laundry. The quantification of environmental impacts was performed through a life cycle assessment, using CML 2001 Baseline method. The necessary materials and processes were considered in each scenario according to the lifecycle stages (i.e., materials, construction, transportation, use, and deconstruction) and subsystems.Results and discussionThe environmental characterization indicated that the best scenario in both urban models is the distributed-over-roof tank (D3, C3), which provided a reduction in impacts compared to the worst scenario of up to 73% in diffuse models and even higher in compact ones, 92% in the most dramatic case. The lower impacts are related to the better distribution of tank weight on the building, reducing the reinforcement requirements, and enabling energy savings. The storage subsystem and the materials stage contributed most significantly to the impacts in both urban models. In the compact density model, the underground-tank scenario (C1) presented the largest impacts in most categories due to its higher energy consumption. Additionally, more favorable environmental results were observed in compact densities than in diffuse ones for the Global Warming Potential category along with higher water efficiencies.ConclusionsThe implementation of one particular RWH scenario over another is not irrelevant in drought-stress environments. Selecting the most favorable scenario in the development of newly constructed residential areas provides significant savings in CO2 emissions in comparison with retrofit strategies. Therefore, urban planning should consider the design of RWH infrastructures using environmental criteria in addition to economic, social, and technological factors, adjusting the design to the potential uses for which the rainwater is intended.Recommendations and perspectivesAdditional research is needed to quantify the energy savings associated with the insulation caused by using the tank distributed over the roof. The integration of the economic and social aspects of these infrastructures in the analysis, from a life cycle approach, is necessary for targeting the planning and design of more sustainable cities in an integrated way.

Application of LCSA to used cooking oil waste management

PurposeUsed cooking oil (UCO) is a domestic waste generated as the result of cooking and frying food with vegetable oil. The purpose of this study is to compare the sustainability of three domestic UCO collection systems: through schools (SCH), door-to-door (DTD), and through urban collection centres (UCC), to determine which systems should be promoted for the collection of UCO in cities in Mediterranean countries.MethodsThe present paper uses the recent life cycle sustainability assessment (LCSA) methodology. LCSA is the combination of life cycle assessment (LCA), life cycle costing, and social life cycle assessment (S-LCA).Results and discussionOf the three UCO collection systems compared, the results show that UCC presents the best values for sustainability assessment, followed by DTD and finally SCH system, although there are no substantial differences between DTD and SCH. UCC has the best environmental and economic performance but not for social component. DTD and SCH present suitable values for social performance but not for the environmental and economic components.ConclusionsThe environmental component improves when the collection points are near to citizens’ homes. Depending on the vehicle used in the collection process, the management costs and efficiency can improve. UCO collection systems that carry out different kind of waste (such as UCC) are more sustainable than those that collect only one type of waste. Regarding the methodology used in this paper, the sustainability assessment proposed is suitable for use in decision making to analyse processes, products or services, even so in social assessment an approach is needed to quantify the indicators.Defining units for sustainability quantification is a difficult task because not all social indicators are quantifiable and comparable; some need to be adapted, raising the subjectivity of the analysis. Research into S-LCA and LCSA is recent; more research is needed in order to improve the methodology.

Financial and environmental modelling of water hardness — Implications for utilising harvested rainwater in washing machines

A study was conducted to determine the financial and environmental effects of water quality on rainwater harvesting systems. The potential for replacing tap water used in washing machines with rainwater was studied, and then analysis presented in this paper is valid for applications that include washing machines where tap water hardness may be important. A wide range of weather conditions, such as rainfall (284-1,794 mm/year); water hardness (14-315 mg/L CaCO3); tap water prices (0.85-2.65 Euros/m(3)) in different Spanish urban areas (from individual buildings to whole neighbourhoods); and other scenarios (including materials and water storage capacity) were analysed. Rainfall was essential for rainwater harvesting, but the tap water prices and the water hardness were the main factors for consideration in the financial and the environmental analyses, respectively. The local tap water hardness and prices can cause greater financial and environmental impacts than the type of material used for the water storage tank or the volume of the tank. The use of rainwater as a substitute for hard water in washing machines favours financial analysis. Although tap water hardness significantly affects the financial analysis, the greatest effect was found in the environmental analysis. When hard tap water needed to be replaced, it was found that a water price of 1 Euro/m(3) could render the use of rainwater financially feasible when using large-scale rainwater harvesting systems. When the water hardness was greater than 300 mg/L CaCO3, a financial analysis revealed that an net present value greater than 270 Euros/dwelling could be obtained at the neighbourhood scale, and there could be a reduction in the Global Warming Potential (100 years) ranging between 35 and 101 kg CO2 eq./dwelling/year.

Contribution of plastic waste recovery to greenhouse gas (GHG) savings in Spain

This paper concentrates on the quantification of greenhouse gas (GHG) emissions of post-consumer plastic waste recovery (material or energy) by considering the influence of the plastic waste quality (high or low), the recycled plastic applications (virgin plastic substitution or non-plastic substitution) and the markets of recovered plastic (regional or global). The aim is to quantify the environmental consequences of different alternatives in order to evaluate opportunities and limitations to select the best and most feasible plastic waste recovery option to decrease the GHG emissions. The methodologies of material flow analysis (MFA) for a time period of thirteen years and consequential life cycle assessment (CLCA) have been integrated. The study focuses on Spain as a representative country for Europe. The results show that to improve resource efficiency and avoid more GHG emissions, the options for plastic waste management are dependent on the quality of the recovered plastic. The results also show that there is an increasing trend of exporting plastic waste for recycling, mainly to China, that reduces the GHG benefits from recycling, suggesting that a new focus should be introduced to take into account the split between local recycling and exporting.

Carbon and water footprint of pork supply chain in Catalonia: From feed to final products.

A systematic tool to assess the Carbon Footprint (CF) and Water Footprint (WF) of pork production companies was developed and applied to representative Catalan companies. To do so, a cradle-to-gate environmental assessment was carried out by means of the LCA methodology, taking into account all the stages involved in the pork chain, from feed production to the processing of final products, ready for distribution. In this approach, the environmental results are reported based on eight different functional units (FUs) according to the main pork products obtained. With the aim of ensuring the reliability of the results and facilitating the comparison with other available reports, the Product Category Rules (PCR) for Catalan pork sector were also defined as a basis for calculations. The characterization results show fodder production as the main contributor to the global environmental burdens, with contributions higher than 76% regardless the environmental indicator or the life cycle stage considered, which is in agreement with other published data. In contrast, the results in terms of CF and WF lay above the range of values reported elsewhere. However, major discrepancies are mainly due to the differences in the co-products allocation criteria. In this sense, economic/physical allocation and/or system expansion have been mostly considered in literature. In contrast, no allocation was considered appropriate in this study, according to the characteristics of the industries and products under assessment; thus, the major impacts fall on the main product, which derives on comparatively higher environmental burdens. Finally, due to the relevance of fodder production in the overall impact assessment results, strategies to reduce greenhouse gases (GHG) emissions as well as water use associated to this stage were proposed in the pork supply chain.

Introduction to the Eco-Design Methodology and the Role of Product Carbon Footprint

Eco-design is used as a tool in the manufacturing and services sectors for improving the sustainability of products by integrating environmental aspects into the design stage, where most of the product impacts are determined. Laws (e.g., EU eco-design directive) and international schemes (e.g., ISO 14006) have encouraged the use of eco-design by companies; in addition, the literature has reported advances in methodology and widespread case studies in different economic sectors. This chapter aims to show a combined design for environment (DfE) and life cycle assessment (LCA) methodology for the implementation of eco-design by companies. The steps and tools of the methodology, as well as the most common strategies, are described. Product carbon footprint (PCF) plays an important role in the methodology in two main ways. First, PCF is one of the indicators that can be calculated with LCA, which has become a common environmental indicator used by companies, not only as quantitative data of the current environmental performance but also as a benchmark for further improvements. Second, PCF is used as a strategy for environmental communication to consumers through eco-labeling. The main strength of the carbon footprint is that stakeholders (business and consumers) are aware of and understand its meaning due to the presence of carbon emissions and global warming in mass media and public science studies.

LCM of Rainwater Harvesting Systems in Emerging Neighbourhoods in Colombia

Potential environmental impacts of water harvesting systems for rain to emerging neighbourhoods in Colombia were studied. Two tools were integrated into a simulation model (life cycle analysis and system dynamics). This was performed as an application case study in two urban areas of Colombia (Bogota and Pereira). We modelled a standard neighbourhood with 10 residential 5-storey buildings of 24 apartments. The results show that it is possible to avoid in every neighbourhood 150,729 kg CO2e and 44,857 kg CO2e, respectively.

Environmental assessment of the entire pork value chain in Catalonia – A strategy to work towards Circular Economy

Pork industry in Catalonia plays a foremost and representative role in the Spanish pork sector. Beyond the economic benefits, conventional practices in the pork industry also imply a number of environmental impacts that need to be dealt with. In this context, the environmental performance of traditional linear pork chain in Catalonia was evaluated through a LCA approach. The outcomes of the analysis showed that both fodder production and transport activities were identified as the critical stages of the system. Accordingly, alternative schemes based on circular economy principles were proposed and potential environmental credits were estimated. Within this framework, comparative results highlighted the advantages of moving towards a closing loop production system, where resource efficiency and waste valorisation were prioritised over final disposal options.

Eco-Design and Product Carbon Footprint Use in the Packaging Sector

Packaging products are common in all industrial sectors and in the market place. However, packaging design needs to be optimized while avoiding superfluous designs that do not consider the environment in their design. Directive 94/62/EC established a framework in order to harmonize the environmental requirements for packaging as well as to determine targets for recycling and recovering packaging waste. In this chapter, the eco-design projects of different sectors are presented in order to show the different strategies that are used to improve the environmental performance of packaging products. The carbon footprint of the products is quantified and used as an environmental indicator. Common strategies to reduce the carbon footprint of packaging are optimizing the volume (and therefore reducing the transportation requirements), using renewable materials, and optimizing the end-of-life management.