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Abstract Lighting simulation is a useful instrument in predicting lighting conditions in buildings. Modelers can use several matrix methods according to the buildings’ characteristics and the objectives of the analysis. However, it is unknown which methods are the most appropriate for lighting analysis of heritage buildings. The Joanina Library located in the University of Coimbra – a World Heritage building – was used to compare different matrix methods (2PH, 3PH, and 5PH) under several solar models (BRL, DISC, Perez, and Reindl) using Radiance-based simulations. On-site measurements (indoor and outdoor) were used to calculate each method’s accuracy under different solar models. The combination of the 2PH method with the DISC solar model presented the highest accuracy with an average MBEr and RMSEr of 2.8 % and 43.6 %, respectively. Therefore, the 2PH method was the best choice for the case study, even though the 3PH method may also be considered, especially for parametric studies of improving measures.

Abstract Despite the significant growth in the number of published life-cycle assessments of biofuels, important aspects have not captured sufficient attention, namely soil carbon emissions from land use change (LUC) and uncertainty analysis. The main goal of this article is to evaluate the implications of different LUC scenarios and uncertainty in the life-cycle energy renewability efficiency and GHG (greenhouse gases) intensity of wheat-based bioethanol replacing gasoline. A comprehensive assessment of different LUC scenarios (grassland or cropland converted to wheat cultivation) and agricultural practices is conducted, which results in different carbon stock change values. The types of uncertainty addressed include parameter uncertainty (propagated into LC (life-cycle) results using Monte-Carlo simulation) and uncertainty concerning how bioethanol co-product credits are accounted for. Results show that GHG emissions have considerably higher uncertainty than energy efficiency values, mainly due to soil carbon emissions from direct LUC and N2O release from cultivated soil. Moreover, LUC dominates the GHG intensity of bioethanol. Very different GHG emissions are calculated depending on the LUC scenario considered. Conversion of full- or low-tillage croplands to wheat cultivation results in bioethanol GHG emissions lower than gasoline emissions, whereas conversion of grassland does not contribute to bioethanol GHG savings over gasoline in the short- to mid-term.

Abstract This paper presents a new methodology for impact assessment—SIAM (Spatial Impact Assessment Methodology)—which is based on the assumption that the importance of environmental impacts is dependent, among other things, on the spatial distribution of the effects and of the affected environment. The information generated by the use of Geographical Information Systems (GIS) in impact identification and prediction stages of Environmental Impact Assessment (EIA) is used in the assessment of impact significance by the computation of a set of impact indices. For each environmental component (e.g., air pollution, water resources, biological resources), impact indices are calculated based on the spatial distribution of impacts. A case study of impact evaluation of a proposed highway in Central Portugal illustrates the application of the methodology and shows its capabilities to be adapted to the particular characteristics of a given EIA problem.

Metal accumulation by Juncus maritimus and the effect this plant might have on the physico-chemical composition of sediments, from Douro river estuary (NW Portugal), were investigated through one year of plant's life. The contents of Al, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn were determined (by atomic absorption spectrophotometry) in sediments, rhizosediments (those among plant roots and rhizomes) and different tissues of J. maritimus. Two estuarine sites with different characteristics were studied, one a sandy sediment with relatively low organic matter content, the other a muddy site. The role of the plant seemed to be markedly dependent on the sediment composition. At the sandy site, significant variations throughout the year (a decrease from winter to summer and an increase in autumn) either in rhizosediment and sediment or in J. maritimus roots were only observed in Cd and Cu levels. These variations were the same in both compartments, probably caused by tidal water movements and the activity of the plant. At the muddy site, variations throughout the year were observed for all studied elements but Pb. Changes in the Cd and Zn contents of roots were opposite to those in the rhizosediment (uptake of Cd and Zn by J. maritimus roots in summer may have caused a decrease in rhizosediment levels). Fe and Mn showed similar patterns of variation in both roots and rhizosediment (contents significantly increasing in summer). Higher contents of Fe and Mn in roots in summer could be related to changes in mass, higher availability of the elements, or accumulation at the surface of the root in (hydr)oxides forms. For the remaining elements no significant correlations between rhizosediment and roots variations were observed, indicating that their uptake and release by roots were not based on single exchanges with the sediment. J. maritimus showed capacity to accumulate Cu, Zn and particularly Cd, thus appearing to be useful for the phytostabilization of these metals.

Uninterruptible power supplies (UPS) are key components of information and communications technologies (ICT) systems, ensuring reliability by maintaining the continuity and quality of the systems’ power supply. The energy consumption of UPS should be an important consideration due to its high impact on the lifecycle costs, but in most applications of UPS, energy efficiency is not the most important issue, since the operational reliability of the ICT systems and the related security of data processing and storage are the major concerns. However, the conversion efficiency of UPS systems has been improving in recent years and high energy savings can be achieved with the adoption of new technologies without a reduction of the reliability levels. The Ecodesign Preparatory Study for UPS (Lot 27) aimed to identify and recommend ways to improve, at their design phase, the environmental performance of UPS in the European Union throughout their lifetime. This paper presents the work developed during the Preparatory Study for UPS focused on the technical analysis of the best available and not yet available technologies, as well as the potential energy savings that can be achieved. Several technologies were considered at component and product level. The main design options were then modelled, and the potential energy savings achievable with policy options focused on minimum efficiency performance standards and energy labelling were assessed, showing a potential for energy savings in European Union in 2025 of 11.4 TWh (65 % energy saving relative to predicted energy requirement of EU ICT system UPS based on current practice).

In the context of globalisation, is a country’s level of development an obstacle to its environmental performance? The main objective of this research is to identify the role played in the environmental performance of countries with different levels of development, globalisation, and environmental regulation, by the three dimensions and two new measures of globalisation, de jure and de facto. This analysis was accomplished by assessing the environmental curve which relates economic growth to environmental degradation, known as the environmental Kuznets curve, for a sample of 32 developed and 26 developing economies from 1995 to 2017. It was found that developed countries produced an inverted U-shaped curve and that globalisation had a mostly beneficial effect on the environment. In contrast, developing economies produced a U-shaped curve and globalisation was generally harmful. Globalisation caused reductions of 0.88% and 0.85% in the environmental degradation of developed countries, and increases of 0.20% and 0.52% in developing ones. Political globalisation produced different effects for each measure in developed countries and had no effect in developing countries. Economic globalisation suggests the relocation of polluting industries from developed to developing countries. As there is currently very little literature on the new measures of globalisation, this study provides fresh insights for policymakers devising appropriate measures to achieve sustainability in both developed and developing countries.

Globalization as a mechanism to connect people at distance and share knowledge has been flourishing. Simultaneously, environmental degradation has been increasing, as reflected in global warming. Through three dimensions, the economic, the social and political, and two measures, de jure and de facto, this study provides a disaggregated analysis of the effect of globalization on the critical issue of global warming for 25 European Union countries from 1990 to 2016. To emphasize globalization, the countries analysed were evaluated by two measures of globalization, de jure and de facto, resulting in their classification as high or low globalized countries de jure and de facto. Furthermore, energy consumption, economic growth and efficiency were included in an Autoregressive Distributed Lag model performed with the Driscoll-Kraay estimator. Robustness was checked using a Feasible Generalized Least Squares estimator. The results revealed that, overall, globalization increases environmental degradation, with the de jure measure having greater influence on high-globalized countries and the de facto measure having greater influence on low-globalized countries. Bearing in mind the increase in worldwide emissions driven by globalization, practices such as the relocation of polluting industries from high globalized countries should be discouraged. Incentives to harmonize global environmental restrictions could contribute to decarbonization worldwide.

Abstract The world has been experiencing a significant increase in daily average temperatures per decade and climate change scenarios are projecting high probability of more frequent heat waves. In vulnerable regions, like Southern Europe, where most of the residential buildings still rely on natural ventilation for cooling, impact on thermal comfort can be significant in terms of health, well-being and also energy consumption. The question is particularly important for the existing building stock, which was not designed considering the projected future climate conditions and is prone to be subjected to interventions with the purpose of improving thermal performance. The study presents a vulnerability framework and methodology for the assessment of thermal comfort in existing dwellings in the context of climate change. Results relating to a 1960s typical building case study in Lisbon, Portugal, suggest that specific dwelling characteristics, such as orientation, and occupancy profiles are relevant when assessing vulnerability, suggesting significant differences, of up to 91% in discomfort hours on an annual basis. Furthermore, increased insulation seems to be effective in decreasing discomfort, as the best results (48% in discomfort hours decrease) stem from a context of external insulation for a heatwave situation. The methodology can be useful for assessing vulnerability in existing dwellings and its specific conditions. It can also contribute to understanding the effect of energy retrofitting measures in future climate conditions, assisting energy efficiency policies and decision-making regarding retrofit interventions.

The intensive agricultural practices are increasing the demand for chemical fertilizers, being currently produced from a non-environmental friendly way. Besides the environmental impacts, the nutrient uptake efficiency by the crops is very low, representing huge losses into the fields. Therefore, it is crucial to study alternatives for the current chemical fertilizers, which simultaneous improve nutrient efficiency and minimize environmental impacts. A sustainable solution is to recover nutrients from wastewater streams with microalgal cultures and the biomass conversion into bio-char for soil amendment. Wastewaters are loaded with nitrogen and phosphorus and can be used as culture medium for microalgae. Thus, nutrients can be recycled, reducing the requirement of chemical fertilizers. This paper aims to review nutrient recovery from wastewater using microalgae and the biomass conversion into bio-char. This process promotes nutrient recycling and the bio-char (when added to soil) improves the nutrient uptake efficiency by crops.