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Battery Electric Vehicles (BEV) are considered to be a better alternative for conventional vehicles in the matter of carbon dioxide (CO 2 ) emissions and urban air pollution reduction. Life Cycle Assessment (LCA) is a widely used methodology to quantify and compare the environmental impacts of vehicle technologies. In this study, we compare the life cycle environmental emissions of CO 2 equivalent (CO 2e ), sulfur dioxide (SO 2 ), nitrogen oxides (NO X ) and particulate matters (PM) of the BEV with the petrol and diesel vehicles. Unlike many other literatures, this study uses the real-world energy consumption data for the environmental assessment. In addition, this study explores the possible impact of the short term and long term fluctuations in the electricity mix and the vehicle charging profile, on the life cycle emissions performance of BEV. The influence of charging profile on the well-to-tank (WTT) emissions (i.e. emissions associated with electricity production) of BEV is discussed by using hourly emissions and different possible peak and off-peak charging time frames. The results of this study proves off-peak charging is a better option to reduce the life cycle emissions, compared to peak charging. When a BEV is charged during off-peak hours instead of peak hours, the well-to-tank CO 2 , SO 2 , NO X and PM emissions per km can be reduced significantly. Also, this study emphasizes the importance of taking driving behaviors of users and auxiliary energy consumption into account. This aspect is analyzed by comparing the empirical energy consumption and the corresponding WTT emissions of BEV, with the New European Driving Cycle (NEDC) standard values. The results reveal that the auxiliary energy consumption is responsible for, nearly a third of the WTT emissions. [ABSTRACT FROM AUTHOR]

The massive data centre energy consumption has motivated significant efforts to use energy efficiency strategies and the implementation of renewable energy sources that reduce their operational costs and environmental impact. Considering that the potential of many of these measures is often closely linked to the climate conditions, the location of data centres can have a major impact on their energy demand. Moreover, from a holistic approach, differences among regions become even more important when accounting for the electricity attributes from the grid. To assess these differences this work compares by the use of energy indicators the behaviour of a data centre located at different representative emplacements in Europe. To do so, a dynamic energy model which incorporates free cooling strategy and photovoltaic energy is developed. The paper concludes by suggesting that future data centre developments could consider site selection as a new strategy to limit the environmental impact attributable to this sector. [ABSTRACT FROM AUTHOR]

The Portuguese electricity mix is undergoing a significant shift away from the technologies that have dominated generation for the past decades. This article aims at assessing the environmental life-cycle impacts of electricity generation and supply in Portugal (PT), including: (i) modeling the main electricity generation systems; (ii) modeling the transmission and distribution (T&D) grid infrastructure; (iii) characterizing the evolution of the electricity sector in PT from 2003 to 2012; and (iv) discussing how the recent changes in the technology portfolio affected the environmental performance of the electricity generated and supplied. The life-cycle assessment methodology was used to quantify impacts in: non-renewable fossil energy demand (nREn), global warming (GW), abiotic depletion (AD), acidification (AC), eutrophication (ET), photochemical oxidation (PO) and ozone layer depletion (OD). From 2003 to 2012, an overall reduction of the environmental impacts was achieved. In particular, since 2008, electricity generation impacts in AC and PO dropped sharply as a result of the installation of desulphurization (62% reduction in AC; 74% reduction in PO) and denitrification (5% reduction in AC) systems in coal power plants (PP), as well as the phase out of large fuel oil PP. For NREn, AD and GW, the reduction of impacts was less pronounced (9–22% in the generation mix; 14–22% in the supply mix). T&D grid added 5–14% to the environmental impacts due to infrastructure (<5%) and T&D losses (5–9%). Despite the large increase in renewable capacity (especially wind) and the investments in lower-carbon fossil fuel technologies (natural gas), electricity generation still relies heavily on coal. There is, however, potential to further reduce environmental impacts in key categories (NREn, AD and GW) since there is significant available capacity of natural gas combined cycle currently underutilized. [ABSTRACT FROM AUTHOR]