• Energy Research

In recent years, waste management systems have been evaluated using a life cycle assessment (LCA) approach. A main shortcoming of prior studies was the focus on a mixture of waste with different characteristics. The estimation of emissions and consumptions associated with each waste fraction in these studies presented allocation problems. Waste-to-energy (WTE) incineration is a clear example in which municipal solid waste (MSW), comprising many types of materials, is processed to produce several outputs. This paper investigates an approach to better understand incineration processes in Spain and Portugal by applying a multi-input/output allocation model. The application of this model enabled predictions of WTE inputs and outputs, including the consumption of ancillary materials and combustibles, air emissions, solid wastes, and the energy produced during the combustion of each waste fraction.

The big challenge of the next decades is meeting the global nutritional demand, while reducing the pressure on food resources and the GHG emissions. In this regard, the overall goal consists of redesigning the food systems and promoting sustainable dietary patterns is a crucial aspect. This article focuses on reviewing the state-of-the-art of the combined Life Cycle Assessment (LCA) and the Water-Energy-Food (WEF) Nexus approach in assessing the effects of diet transitions. Diet LCAs differ in methodology, design, and assessed environmental impacts. The WEF nexus, which aims at finding synergies and trade-offs between the water, energy, and food resources systems, has been applied to different contexts and levels. However, a limited number of nexus methods have been developed at the food and diet levels, and no commonly recognizable methodology for the nexus assessment has been achieved. An integrated LCA and WEF Nexus approach can be a decisive tool to improve the understanding of the interconnections in the nexus, as it enables the consideration of entire supply chains. This study is part of the Ceres-Procon Project: Food production and consumption strategies for climate change mitigation (CTM2016-76176-C2-2-R) (AEI/FEDER, UE), financed by the Spanish Ministry of Economy and Competitiveness, which aims to determine strategies to improve the sustainability of current food production and consumption.

Contents lists available atScienceDirectSustainable Cities and Societyjournal homepage:www.elsevier.com/locate/scsLife Cycle Assessment of a solar thermal system in Spain, eco-designalternatives and derived climate change scenarios at Spanish and ChineseNational levelsJaume Albertía,¿,1, Juliana Raigosaa,b, Marco Raugeia,c, Rafael Assiegoa,d, Joan Ribas-Tura,e,Núria Garrido-Sorianof, Linghui Zhangg, Guobao Songg, Patxi Hernándezh, Pere Fullana-i-PalmeraaUNESCO Chair in Life Cycle and Climate Change ESCI-UPF, Universitat Pompeu Fabra, Pg. Pujades 1, 08003 Barcelona, SpainbInnovation Center on e-government, Ministry of Information and Communication Technologies, Bogotá, ColombiacFaculty of Technology, Design and Environment, Oxford Brookes University, Wheatley Campus, Oxford OX33 1HX, UKdETS Arquitectura, Energy Group-University of Malaga, Pl. El Ejido s/n, 29071 Málaga, SpaineESCI-UPF Research in International Studies and Economics (RISE), Universitat Pompeu Fabra, Passeig Pujades 1, Barcelona 08003, SpainfSustainability Measurement and Modeling Lab, Universitat Politècnica de Catalunya (UPC), School of Industrial, Aeroespace and Audiovisual Engineering of Terrassa,Colom st., 08222 Barcelona, SpaingKey Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, No. 2Linggong Road, Ganjingzi District, Dalian 116024, PR ChinahTecnalia, Barrio Lasao, E-20730 Azpeitia, Gipuzkoa, SpainARTICLE INFOKeywords:Renewable energiesBuildingCircular economyNational emissionsNationally determined contributionsABSTRACTSolar thermal energy is considered a‘clean’form of energy; however, environmental impacts occur during itslife-cycle. The present work compares the environmental performance of two scenarios: a solar thermal systemfor providing domestic hot water (DHW) used in conjunction with a traditional natural gas heating system, andthe natural gas heating system on its own. Weak points are found and different eco-design scenarios are eval-uated in order to achieve a more circular economy. In addition, the authors explore what would be the nationalGreenhouse Gas emission reduction potential of a wider use of domestic solar hot water systems (DSHW) inChina’s and Spain’s built environment. In this case,five displacement methods are suggested to show how theemissions reduction vary.Through a review of the state of the art and a Life Cycle Assessment of a solar system the two scenarios areassessed. Some impact categories, such as global warming, suggest a markedly better performance of the solarsystem (-65%). However, weak points in the solar solution have been identified as there is an increase of impactsin cases such as acidification (+6%) and eutrophication (+61%), mostly due to the metals used. The compo-nents with higher environmental impact are the collector, the tank, and the copper tubes.The reduction of national emissions by promoting DSHW depends on the actual displaced technology/ies. Theconsequences on national emissions reduction depending on these choices are assessed. The potential reductionof emissions, if 30% of the DHW were covered with solar sources, would be between 0.38% and 0.50% in thecase of Spain and between 0.12% and 0.63% in China. Peer Reviewed

This paper gives an overview of main food supply chain stakeholders and their role in achieving the UN Sustainable Development Goals (SDGs). As this supply chain is global, playing a significant role in feeding the world, a deeper analysis of 17 SDGs, their targets and indicators reveals numerous direct and indirect connections with various SDGs. To perform such an overview, the authors investigated the link between the main stakeholders of the chain (farmers, food processors, food traders and consumers) with UN SDGs. In parallel, the authors explored the roles of policymakers, inspection services, certification bodies and academia in supporting these SDGs. In spite of numerous papers, calculations and estimations, discussion and media coverage, the authors believe that only the tip of the iceberg has been revealed. Based on this overview, the authors emphasize SDG 2—Zero Hunger and SDG 12—Responsible Consumption and Production as the most dominant for the food supply chain. In parallel, the achievement of SDG 17—Partnerships for the Goals will enable deeper intertwining of the goals and all stakeholders in the food supply chain continuum. Additional efforts are needed to pave the way for fulfilling the targets of the UN SDGs and exceeding expectations of all stakeholders.

The use of functional fillers can be advantageous in terms of cost reduction and improved properties in plastics. There are many types of fillers used in industry, organic and inorganic, with a wide application area. As a response to the growing concerns about environmental damage that plastics cause, recently fillers have started to be considered as a way to reduce it by decreasing the need for petrochemical resources. Life cycle assessment (LCA) is identified as a proper tool to evaluate potential environmental impacts of products or systems. Therefore, in this study, the literature regarding LCA of plastics with functional fillers was reviewed in order to see if the use of fillers in plastics could be environmentally helpful. It was interesting to find out that environmental impacts of functional fillers in plastics had not been studied too often, especially in the case of inorganic fillers. Therefore, a gap in the literature was identified for the future works. Results of the study showed that, although there were not many and some differences exist among the LCA studies, the use of fillers in plastics industry may help to reduce environmental emissions. In addition, how LCA methodology was applied to these materials was also investigated.

One of the main drivers for companies to perform environmental improvements is economic benefit, either by obtaining a more valuable product or gaining new customers. Circular economy combines environmental improvements with these drivers to achieve higher and quicker benefits. This paper is a case study on packaging eco-design aligned with circular economy strategy along the production chain. Life cycle assessment (LCA) was used to identify the product life cycle stages where the application of eco-design strategies would be more efficient (in this case, raw materials production from virgin petrochemicals). To improve the environmental profile of this packaging, virgin petrochemicals were partially replaced by mineral fillers (calcium carbonate based) or/and post-consumer recycled plastics. Different technically compliant cosmetic tubes were produced by collaboration between a company producing the plastic granulates with mineral fillers and a company producing the cosmetic tubes and cradle-to-gate LCA were performed. The replacement of virgin petrochemicals by mineral fillers helped to reduce the environmental impacts by an average of 12% and the use of post-consumer recycled plastic further decreased emissions up to 29% for 6 out of the 9 evaluated impact categories. The option with better environmental performance was also the one with lower economic costs. According to the involved companies, LCA combined with ecodesign helped to achieve efficient environmental and economic savings. The findings are important for the plastic packaging sector because they tackle with prime concerns, like plastic debris, climate change and resource depletion. They are of main interest for industrial activities where brand positioning is a priority (i.e. cosmetics).

Cadmium telluride photovoltaics (CdTe PV) have grown considerably in the last few years and are now a mainstream energy technology. Concern has been voiced regarding the potential impact caused by the dispersal of the Cd contained in the modules after they are decommissioned. This study presents a new comprehensive analysis of the end-of-life of CdTe PV and reports on the associated Cd emissions to air and water. Three end-of-life scenarios were considered for CdTe PV. In the first one, 100% of the modules are collected and sent to recycling; in the other two, 85% of the modules are recycled, and the rest are assumed to be either treated as normal municipal solid waste or pre-selected and sent to landfills. All input and output data for module decommissioning and recycling were based on the information directly provided by the world-leading CdTe PV manufacturer (First Solar). The inventory modelling was performed with the GaBi life cycle analysis software package in conjunction with the Ecoinvent v.2 database. In all scenarios, end-of-life Cd emissions from CdTe PV were found to be relatively low, for instance when compared to those from NiCd batteries, when expressed per kilogram of Cd content. The on-going growth of CdTe PV is unlikely to produce a worrisome increase in the overall Cd emissions to the environment; principally thanks to the expected stringent control of the related Cd-containing waste flows.

The United Nations has adopted 17 sustainable development goals for 2030 with environmental sustainability being one of the main pillars. A key point to address this pillar is the proper management of waste generation. Within the broad spectrum of waste types, food loss and waste is produced worldwide in large quantities. In this framework, the development of composite indexes is recommended to measure the level of compliance of any context with Sustainable Development Goals. This work presents a novel composite index for food loss and waste generation and management systems, the so-called sustainable development goals-food (SDG-Food) index, aiming to determine the level of compliance of any concrete national, regional, or local context regarding five different sustainable development goals with a water-climate-food nexus thinking. The pilot case study of Spain is presented by analyzing the environmental performance between 2015 and 2040 in a context of (i) compliance and (ii) non-compliance with the Paris Agreement targets. Additionally, four different diets are assessed. Results suggested a numerical index score of 13.79, highlighting the categories of eggs, cereals, meat, and vegetables, and the stages of agricultural production and consumption, as the furthers ones for compliance with the five SDG assessed. Moreover, the scenario of compliance with the Paris agreement targets presented better values for all stages, and a vegan diet was highlighted as the one with the best index score.