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This paper presents a case study describing the impact of charging process of plug in hybrid vehicles (PHEV) and all electrical vehicles (EV) on the supply grid. The paper shows the distortion produced in the grid by the simultaneous charge of a large fleet of vehicles and the corrective actions taken to guarantee the Electromagnetic Compatibility with other loads in the same grid. The goal of the investigation was to establish a design guide for parking facilities. Peer Reviewed

The aim of this paper was to analyse how changes in wave patterns, due to the effect of climate change, can affect wave energy power and yield around Menorca (NW Mediterranean Sea). The present and future wave energy conditions were derived from recently developed high-resolution wave projections in the NW Mediterranean. These wave projections were forced by surface wind fields obtained, respectively, by 5 different combinations of global and regional circulation models (GCMs and RCMs) for the A1B scenario. The results showed that the projected future spatial and directional distributions of wave energy are very similar to those of the present conditions. The multi-model ensemble average illustrated a slight general decrease in the annual and seasonal wave power (except for summer). However, the inter-model variability is large since two models showed opposite trends to the other 3 in most cases. Such inter-model variability is lower(higher) for winter(autumn). Another result is the reduction of the temporal variability in the future, considering both the multi-model mean and each single model projection. Such a decrease is consistent with the future seasonal redistribution of energy throughout the year. This would entail an increase in the efficiency of wave energy converters deployed in this area due to the more regular temporal distribution of the energy. Peer Reviewed

AbstractAlthough jet fires are usually smaller than other fires, they may lead to a destructive chain of events that can increase the scale of an accident. Therefore, their size should be predicted for accurate risk assessment. In the literature, most of the proposals for estimating jet fire size concern small jet fires (up to 2.5 m in length) or subsonic flames. In this study, experiments on relatively large propane jet fires in still air were performed. Vertical turbulent diffusion flames up to 10 m in length, with sonic and subsonic mass flow rates, were obtained using six different orifice exit diameters. The experiments were filmed with video and thermographic cameras and the resulting visible and infrared images were used to determine flame length and lift‐off distance. Expressions for estimating jet length as a function of several variables (mass flow rate, orifice exit diameter, Froude and Reynolds numbers) are also proposed. © 2008 American Institute of Chemical Engineers AIChE J, 2009

"Formerly known as Journal of Molecular Catalysis A: Chemical" The thermal properties of various alkyl threo-9, 10-dihydroxystearates (DHSEs) prepared from non-edible fat were studied. Non-edible animal fat was hydrolyzed in a 93% yield with R. oryzae resting cells. Crude unsaturated fatty acids were recovered from the matter liquor resulting from a crystallization performed to achieve the saturated fatty acids. These unsaturated free fatty acids were epoxidized with 30% H2O2 using immobilized Candida antarctica Lipase-B (CAL-B) as biocatalyst. The epoxy ring was cleaved with hot water in the presence of tert-butanol (t-BuOH). Pure threo-9, 10-dihydroxystearic acid (DHSA) from animal fat was recovered by crystallization (51% yield). Subsequently, DHSA was esterified in alpha-limonene using biocatalysts yielding twelve DHSEs (58-90% yield). Differential scanning calorimetry (DSC) analysis of these esters revealed potential latent heats ranging from 136.83 kJ kg−1 to 234.22 kJ kg−1 and melting temperatures from 52.45 ◦C to 76.88 ◦C. Finally, the compounds with enthalpies above 200 kJ kg−1 were subjected to 100 and 1000 thermal cycles. These experiments showed that these products present good thermal reliability. GREA and DBA are certified agents TECNIO in the category of technology developers from the Government of Catalonia. We thanks to Subproductos Cárnicos Echevarria y Asociados S.L (Cervera, Spain) for supplying the non-edible fat. Moreover, the research leading to these results has received funding from the European Commission Seventh Framework Programme (FP/2007-2013) under grant agreement no PIRSES-GA-2013-610692 (INNOSTORAGE) and from the European Union’s Horizon 2020 research and innovation program under grant agreement no 657466 (INPATH-TES). The authors would like to thank the Catalan Government for the quality accreditation given to their research groups GREA (2014 SGR 123) and Agricultural Biotechnology Research Group (2014 SGR 1296). This work has been partially funded by the Spanish government (CTQ2015-70982-C3-1-R (MINECO/FEDER) and ENE2015-64117-C5-1-R (MINECO/FEDER). Aran Solé would like to thank Ministerio de Economía y Competitividad de España for Grant Juan de la Cierva, FJCI-2015-25741.

The electric grid is evolving. Smart grids and demand response systems will increase the performance of the grid in terms of cost efficiency, resilience and safety. Accurate load forecasting is an important issue in the daily operation and control of a power system. A suitable short term load forecasting will enable a utility provider to plan the resources and also to take control measures to balance the supply and demand of electricity. The aim of this paper is to create a method to forecast the electric load in a non-residential building. Another goal is to analyse what kind of data, as weather, indoor ambient, calendar and building occupancy, is the most relevant in building load forecasting. A simple method, tested with three different models, such as MLR, MLP and SVR, is proposed. The results, from a real case study in the University of Girona, show that the proposed forecast method has high accuracy and low computational cost This research has been partially supported by the Spanish Government project MESC (Ref. DPI2013-47450-C2-1-R). Also we would like to thank the Department of Physics and acknowledge the technical assistance and maintenance service of the UdG (SOTIM) which provided the weather and consumption data respectively. The authors belong to the ‘Smart IT Engineering and Solutions’ accredited research group (Generalitat de Catalunya, 2014 SGR 1052)

Energy recovery elements play a major role in the efficiency and sustainability of building ventilation systems. The use of a sensible or total energy recovery ventilator is a key decision for ventilation systems designers. However, there is a lack of technical tools and developments to support this decision. The authors present a procedure to develop a simple decision tool for designers based on hourly values of the outdoor weather conditions and that can be applied to any kind of building. Results of the procedure are presented in simple-to-use isoline maps and tables. In order to assess credibility of the model used in the procedure, data published in the literature have been used as a reference, showing good accordance. As an example, the procedure has been applied to the Spanish area considering 48 different locations. Results have been presented and discussed. Their analysis shows as the market-accepted recommendation of using energy recovery ventilators in locations with high relative humidity during the summer should be reconsidered. Peer Reviewed

ABSTRACT This paper examines the suitability of partially replacing natural aggregate, sand, (NA) with recycled concrete aggregate (RCA) or lightweight aggregate (LWA) in mortars, under the hypothesis that pre-wetting aggregates would produce improvement in mortar properties. Fresh mortar properties such as density, entrained air content, consistency and heat of hydration, as well as hardened mortar properties such as dry density, compressive and flexural strength, and dimensional instability at 0% and 100% saturation were determined. The results show that mortars made with natural aggregate (75%) and recycled concrete aggregate (25%) have similar properties to mortars made with only natural aggregate (100%) and that pre-wetting the aggregates does not influence the properties of mortars significantly. Therefore, partial replacement with recycled concrete aggregate is a viable alternative for producing mortar.