Browsing by Keyword "Energy consumption"

Now showing 1 - 4 of 4
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    Comparison of different Hybrid Electric Vehicles concepts in terms of consumption and efficiency
    (2012) Torres, O.; Bader, B.; Romeral, J. L.; Lux, G.; Ortega, J. A.; FACTORY
    The objective of this paper is to compare the most common HEV power train stractures. As a first step, forward and backward models of these vehicle concepts are implemented using Modelica/Dymola in order to evaluate and compare the energy consumption. Taking into account fuel/electrical consumption and the losses in the powertrain components, a comparison of two different alternatives of Hybrid Electric Vehicle models (parallel structure and Range Extender) are presented in this publication. To simulate these models using different driving cycles, a rule-based operating strategy is implemented. As a second step, a Dynamic Programming (DP) based algorithm is applied to these models. This algorithm is used to determine the optimal fuel consumption for given driving cycles. A comparison of the DP results and rule-based results is carried out to evaluate the potential improvement that is possible to achieve optimizing the energy management strategy and the size of the powertrain components.
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    Comparison of nanoclay/polyvinyl alcohol aerogels scale production: Life Cycle Assessment
    (2021-12) Parascanu, María Magdalena; Esteban-Arranz, Adrián; de la Osa, Ana Raquel; Romero, Amaya; Sánchez-Silva, Luz; ECONOMÍA CIRCULAR
    Nowadays, organic aerogels have arisen as promising materials for different applications such as: building, construction, energy among others, due to their low density, high thermal insulation capacity and high porosity. In the recent years multiple procedures to synthesize them have been developed, however, the freeze-drying method has gained more importance, being considered a cost-competitive, eco-friendly, and efficient process. Therefore, it is fundamental to evaluate its environmental impacts for its future implementation as a sustainable industrial process. In this work, a Life Cycle Assessment on the synthesis of nanoclay reinforced polyvinyl alcohol aerogels by freeze-drying has been carried out. Furthermore, the influence of the production scale (laboratory and pilot line) and the functional unit (1 kg and 1 m3) have been studied. Additionally, different upgrading approaches carried out in the pilot line, energy efficiency and production capacity, have been evaluated. Results demonstrated that better environmental impact values were obtained with pilot line aerogel production in comparison to laboratory scale for both functional units. Regarding the different upgrade assessment with the pilot line, it has been concluded that the background processes and the energy consumption are the main causes for the increment in the environmental impact values during the aerogel synthesis.
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    Energy consumption of the nanofibrillation of bleached pulp, wheat straw and recycled newspaper through a grinding process
    (2014) Josset, Sébastien; Orsolini, Paola; Siqueira, Gilberto; Tejado, Alvaro; Tingaut, Philippe; Zimmermann, Tanja; BIOECONOMÍA Y CO2
    Cellulose nanofibrils (CNF) are steadily gaining attention since this material is a renewable alternative to artificial polymers. Moreover, waste products from cellulose-based industries (e.g. paper mills) or from agriculture can be used as raw material for CNF isolation. However, the up-scaling from the laboratory to the industry can only be achieved if the energy costs are low enough to compete against low-price petroleum derivatives. The objective of this work is to present an energy-related study of the direct fibrillation of cellulose-based materials using a grinding process. Two waste materials, namely wheat straw and recycled newspaper, have been investigated as starting materials, together with bleached wood pulp for comparison purposes. The mechanical properties and specific surface areas of the resulting fibrillated materials are then presented and systematically compared with each other. The properties of the bleached wood-pulp fibres exhibited the highest values that were reached already at low energy inputs. The different properties of CNF isolated out the waste materials could reach values close to their maxima for energy inputs as low as about 5 kWh/kg compared to the ca. 10 kWh/kg needed with high pressure homogenization.
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    Energy demands and potential savings in European office buildings: Case studies based on EnergyPlus simulations
    (2013) Boyano, A.; Hernandez, P.; Wolf, O.; PLANIFICACIÓN ENERGÉTICA
    This article presents key energy use figures and explores the energy saving potentials in office buildings across Europe by simulating several currently available scenarios. The information provided in this research work is based on a review of relevant literature and the results of EnergyPlus simulations of a reference office building that can be considered as a representative office building across Europe. Three locations were selected to represent the three climate zones in which Europe was divided. Lighting has been pointed out as an area with significant improvement potentials. These improvements have been investigated by using two scenarios with different lighting control systems. In both cases and regardless of the location of the office building, the energy savings were achieved with already existing technology and will bring important reductions in the overall energy bill. Two further aspects were investigated in this work: the first one is an improvement of the insulation of the windows and the external walls (U-value) and the second one the orientation of the building. Unlikely to the lighting improvements, the location of the buildings highly influences the amount of energy required by HVAC systems. It is observed that higher insulation factors are recommended in cold and medium climate zones while they should be carefully chosen in the warmer climate zones. Office buildings constructed in warm climate zones are subjected to higher heat gains that cannot be easily released from buildings within a well-insulated envelope. Consequently, the energy demand for cooling purposes is increased, affecting the overall energy consumption and the economic performance of the building.