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Providing healthy food for the world’s growing urban population is a recognized global challenge and it is likely that current modes of conventional, large-scale farming will over time be increasingly complemented by local, urban farming practices. Apart from its acknowledged social benefits, urban farming is also widely viewed as a more resource-efficient alternative to conventional remote farming. Especially indoor, soilless cultivation in urban areas is being portrayed as a particularly sustainable solution. However, as this technique relies on controlled environments, its ongoing operation can be quite energy-intensive and related carbon emissions should be carefully weighed against reduced emissions, such as those from transportation. To further this goal, this article presents a simulation-based environmental analysis workflow for Building-Integrated Agriculture (BIA) in urban contexts, that includes detailed solar radiation, water and energy specific models. The aim of the workflow is to guide the user through decision-making on the potentialities of implementing BIA in a given neighborhood while maximizing crop yields and minimizing water and energy consumption. The workflow was applied to three hi-tech urban farming scenarios in Lisbon, Portugal: a polycarbonate Rooftop Greenhouse (RG), a Vertical Farm (VF) with windows and skylights on the top floor of a reinforced-concrete building as well as a completely opaque VF with no penetration of natural light on the ground floor of a reinforced-concrete building. Global Warming Potential (GWP) related to water, transportation and operational energy of these three case studies were compared to GWP of (i) the currently existing supply chain for tomato, and (ii) a hypothetical low-tech unconditioned rooftop urban farm. Results show that the RG and the top floor VF had the best overall environmental performance, respectively cutting greenhouse gas emissions in half and in three in comparison with the existing supply chain for tomato. By allowing this preliminary assessment of alternative farm locations and properties, the workflow provides the user with actionable information for early-stage holistic assessment of BIA projects.

Global food systems are as vital for human survival as they constitute a major threat to the environment, being key drivers of climate change, water use, toxic emissions and habitat change. In a business as usual scenario, these impacts will most likely increase, driven by population and economic growth, which will lead to a higher demand for food, and probably for the most environmentally intensive food categories: meat and dairy products. Existing literature suggests deep paradigmatic changes to address this situation, such as (i) large-scale dietary changes on the consumption side, and (ii) structural changes towards more efficient food supply chains on the production side. As both of these measures are related to urban systems, in terms of food consumption habits and the potential of local production, Urban and Peri-Urban Agriculture (UPA) may assume a relevant role in food systems sustainability. In order to estimate to what extent the implementation of UPA would play a role in mitigating the environmental impacts of urban food systems, this paper uses life cycle assessment (LCA) to estimate their respective mitigation potential. The Global Warming Potential (GWP) and Land use (LU) were assessed for per capita Current Average Consumption (CAC) in Lisbon, and this baseline model was subsequently adapted in order to measure the effects of changes: (i) in the diet, through a comparison with the Recommended Healthy Diet (RHD) model; and (ii) in the food supply chain, by measuring the impacts of eliminating losses and wastage across the food supply chain and shortening transportation distances through local food production. The results show that the highest potential for environmental impacts mitigation is related to dietary changes. However, strategies for enhancing the efficiency of the food supply chain are relevant, as reducing losses and wastage, shortening transportation distances and taking into account technology improvements can further increase the mitigation potential.

District heating networks are commonly assumed in the literature as an environmentally friendly solution for providing heating services for the built environment, due to the centralized heat production located outside urban centers and potential utilization of renewable heat sources (solar, geothermal etc.). However, the impacts associated with both construction and operation phases are frequently overlooked. The main scope of this paper is to make use of the emergy approach to infer environmental performance of the heat provided by district heating networks, considering two types of district heating systems: ESPEX (four-pipe network) and traditional two-pipe district heating network. For centralized heat production, three options were considered: central boiler fueled by fossil fuel mix, natural gas, and solar plant. Additionally, a natural gas distribution network with individual gas boiler in each dwelling was considered. An emergy evaluation was performed to enable the comparison of these systems on the same basis. All systems were applied to the district of Vraen, located in Varnamo, Sweden. The overall results showed that four-pipe ESPEX district heating network with central solar plant is the most suitable solution from the emergy point of view. The second most suitable solution was the two-pipe district heating network with solar plant as the heat production unit. On the other hand, networks with central boiler that used the fuel mixture (bioethanol and fossil fuels) and natural gas had lower environmental performance than the natural gas distribution network with individual boiler in each dwelling.

This article provides an assessment of waste management evolution in Portugal, with a particular emphasis on the performance brought by the adoption of several EPR schemes, namely the ones developed for packaging (general, medicine and plant protection products), used tires, used mineral oils, end-of-life vehicles (ELV), waste electrical and electronic equipment (WEEE), portable batteries and car and industrial batteries. Further, a particular focus is placed on the drivers that influenced the development of such EPR schemes in the country and the challenges facing EPR schemes' development in Portugal. The results achieved in a short period of time suggest that the evolution of the implementation of the EPR concept in Portugal was, so far, successful, not only in quantitative but also in qualitative terms (contributing for a reduction of environmental performance). However, there is still room for improving EPR impact in the long-run and this is largely dependent on policy instruments (of fiscal, information and supervision natures) that can positively influence the context in which EPR schemes operate.

Industrial symbiosis (IS) emerged as a collective, multi-industrial approach to improve economic and environmental performance through the use of wastes/by-products as substitutes for raw materials. The development of IS initiatives depends on the context in which they occur, characterised in terms of social, economic, political, spatial and temporal embeddedness. As a consequence, the context can be influenced to become more supportive of IS through a continuous, interactive process, combining top-down governmental directives and bottom-up spontaneous business initiatives. A strategy to develop and enhance this process is explored in this paper and described by the authors as a middle-out approach. Policies and policy instruments introduced by governmental agencies provide objectives and incentives to businesses. The middle-out approach induces the development of a strategy to create positive feedback loops among agents (e.g. government, industries) that may guide their actions into setting the conditions to support IS emergence. This paper provides a case study that discusses a regional development of IS in Portugal that highlights critical factors for success in implementing IS, and shows that the middle-out approach can also be understood as an extension and combination of previous research on context factors and planned/spontaneous approaches to IS development.

Nowadays, the world faces unprecedented challenges in social, environmental and economical dimensions, in which the industrial design has showed an important contribution with solutions that provide positive answers regarding these problems. In particular, due to its relevance, the automotive industry confronts a moment of crises, and based on the ecodesign of products it has been transforming the challenges in opportunities. In this context, the use of natural fiber composites, produced in developing countries, have presented several social, environmental and economical advantages to design “green” automotive components. Thus, this work through LCA method demonstrates the possibility to use natural fibers through a case study design which investigates the environmental improvements related to the replacement of glass fibers for natural jute fibers, to produce a structural frontal bonnet of an off-road vehicle (Buggy). Results pointed out the advantages of applying jute fiber composites in Buggy enclosures.