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A methodology for the sizing of domestic hot water heating and storage systems is defined, by assuming an extreme operating condition cycle composed of only two parts, a water consumption period and a system repositioning period. In both parts to respond to the extreme hot water demanding conditions, the heating is always on. The subsequent exergy analysis of this domestic hot water production system compares the irreversibility and the exergy efficiency of the water storage and the tankless situation. To carry out such analysis, some basic assumptions were made: a constant temperature heat source, a short duration operating cycle and a constant thermal energy supply. Under these circumstances it is shown that the hot water storage system leads to lower exergy losses while the tankless system is more exergy efficient, but requiring a higher instantaneous thermal power input. The use of the joule effect electricity, as the system heat source, be it a water storage one or a tankless one, maximizes the system irreversibility losses and minimizes the system exergy efficiency. The tankless system, with the joule effect electricity heat source is the worst situation.

In this paper a tool for the evaluation of transmission system adequacy is presented. Although similar in the basic assumptions to the classic versions of the Fuzzy Power Flow (FPF), the approach has significant differences in the formulation. First, it is symmetrical (no influence of the slack bus in the results), so all the fuzzy power injections are in the same situation. Second, by including line constraints, only feasible deterministic power flows are accepted in the fuzzy variables calculations, leading to a more correct representation of the possible impact of uncertainty. Third, recalculation of the estimated node fuzzy injections leads to a clear picture of the repressed power flows and thus of the adequacy of the grid. On the other hand, the Constrained Fuzzy Power Flow (CFPF) separates completely the analysis of the network from the generation influence and costs, which is indispensable in a unbundled organization of the power system.

Abstract Portugal’s performance concerning the Refuse Derived Fuel (RDF) strategy, with particular focus on perspectives for the Northern Region based on the current status of integrated municipal waste management systems in that region, was evaluated. Legal documents, official reports and the market were analyzed. The 2015 national installed capacity of waste treatment technologies, from which the high calorific value fraction (HCVF) for RDF production is obtained, is not far from what was predicted for 2013. However, only around 11% of the HCVF had such destiny and the amount of effectively produced RDF was only 30% of the material sent to RDF production (around 30 kt). In Northern Portugal, no RDF production plant was in operation in 2015; the amount of HCVF was estimated to range from 105 to 204 kt for 2015 and around 2.4 times more is expected in 2020. The strategy laydown for RDF failed so far, and thus, low diversion of waste from landfills is observed, mostly due to low landfill taxes and low HCVF quality, resulting in RDF being non-competitive with the imported higher quality product from countries with very high landfilling fees. Moreover, co-incineration and dedicated recovery solutions are scarce. In the Northern region, the HCVF may be treated in the existing municipal waste incinerator or the RDF might be recovered in new dedicated plants, receiving also non-hazardous waste fractions from other origin. Overall, to ensure a sustainable municipal waste management, the intensification of the reuse, preparation for reuse and recycling of waste components from source segregated collection must be significantly promoted.

The objective of the present work was: (i) to enable biodiesel production from acid waste lard; (ii) to study the esterification reaction as possible pre-treatment at different temperatures, catalyst amount and reaction times; (iii) to evaluate biodiesel quality according to EN 14214 after basic transesterification of the pre-treated fat; and (iv) to predict the impact of using such waste as raw material in mixture with soybean oil. Temperature and catalyst amount were the most important reaction conditions which mostly affected biodiesel quality, namely viscosity and purity. The selected pre-treatment conditions were 65 degrees C, 2.0 wt% H(2)SO(4) and 5 h, which allowed obtaining a product with a viscosity of 4.81 mm(2) s(-1) and a purity of 99.6 wt%. The proposed pre-treatment was effective to enable acid wastes as single raw materials for biodiesel production with acceptable quality; however, low yields were obtained (65 wt%). Alkali transesterification of a mixture of waste lard and soybean oil resulted in a product with a purity of 99.8 wt% and a yield of 77.8 wt%, showing that blending might be an interesting alternative to recycle such wastes. Also, because in addition to using conventional and relatively economical processes, some biodiesel properties depending on the raw material composition (such as the iodine value) might even be improved.

This research work aims to study if it is possible to design a sustainable building residential building that has a life-cycle cost lower than a conventional one. For this purpose, a multifamily cooperative housing building block, that is the Portuguese pilot-project of the EU Project “SHE: Sustainable Housing in Europe”, has been chosen. This work will compare the sustainability of the case study with the conventional design approach in Portugal, i.e. when the conventional technologies and building materials are used. For this outcome, the SBToolPT-H (Portuguese building sustainability assessment and rating methodology) will be used. This paper will highlight the usefulness of a building sustainability assessment tool in supporting and recognising the sustainable building design. It will also show that even with little investment in the capital costs it is possible to achieve high performance residential buildings.

Abstract This paper aims to compare the energy efficiency and CO 2 emissions of four different range extender engine solutions deployed in the same baseline series hybrid vehicle, under a combination of driving scenarios aiming to be representative of typical driving instead of standard cycles. Baseline vehicle is roughly based on Chevy VOLT/Opel Ampera. The baseline internal combustion engine is replaced by an over-expanded cycle engine, Wankel engine and microturbine, with respective generator and exhaust after treatment. Weight savings are compensated by introducing additional battery modules, maintaining the original baseline vehicle curb weight. Vehicle Specific Power (VSP) is used for driving cycle analysis and as explanatory variable for energy consumption and CO 2 emissions variations. Upstream fuel energy and CO 2 emissions of gasoline/diesel and electricity are regarded. Average VSP correlates with variation of the percentage of engine off, potential regenerative braking energy and eco/boost operation. Positive wheel energy correlates with energy consumption and electric autonomy adequately. The vehicle with the lightest engine (Wankel) and largest battery shows to be the most efficient in urban driving (when the engine does not have to work), while the vehicle with the highest efficient engine (over-expanded) and with dual eco/boost setting is the most efficient during the charge sustaining operation and in annual combined use.

Molinate (S-ethyl-azepane-1-carbothioate) is a thiocarbamate herbicide used in rice cultivation for the control of grass weeds. Environmental contamination with molinate is of major concern due to the adverse effects described both for humans and animals. Molinate hydrolase, a novel amidohydrolase previously characterized, is responsible for the initial breakdown of molinate, cleaving the thioester bond of molinate, releasing ethanethiol and azepane-1-carboxylate (ACA). Biotechnology is the key for sustainable farming. With advances in biotechnology, bioremediation has become one of the most rapidly developing fields of environmental restoration. Through the microencapsulation of molinate hydrolase, we are aiming to develop a bioremediation process for the effective molinate degradation in rice paddies. The purpose of this work was to develop and validate an UV method to effectively quantify the substrate (molinate) in further assays with free and microencapsulated molinate hydrolase. The analytical method was validated and the main parameters, as limit of detection, linearity range, precision and accuracy were determined, and compared to those obtained by HPLC (regarding free enzyme kinetics). Both methods show to be linear (r > 0.999) over the concentration range of 0.005-0.150 mM molinate. The global uncertainty, estimated accordingly to the bottom-up approach used by Eurachem, was estimated for both methods. The UV analytical method is effective and seems that it can be applied in future for the quantification of molinate breakdown by free and encapsulated molinate hydrolase.

FCT (Fundacao para a Ciencia e Tecnologia – Portugal) and COMPETE (Programa Operacional de Fatores de Competitividade - Portugal)