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The adoption of electric vehicles (EVs) on a large scale can lead to significant social and economic benefits. The effort of promoting the use of EVs in road transportation is essential to meet the climate change targets and manage the ever unstable prices of perilously diminishing fossil fuels. On the other hand, there are still many uncertainties in the market regarding the acceptability of EVs...
This study aims to evaluate the implications of the use of maritime pine non-debarked wood chips as an alternative solid fuel in industrial boilers in Portugal, highlighting the energy properties and chemical composition of the ash produced. Several samples have been collected from different sources, on which an approximate analysis is carried out to determine the volatile matter content, fixed carbon...
The aim of this paper is to avoid overloading a private customer distribution transformer (DT) in a Portuguese insular area through the means of a new smart electric vehicle (EV) charging scheduler. Firstly, the consequence of the penetration of EVs on the dielectric oil deterioration of the DT of the industrial unit is estimated. The workplace allows the EVs to charge while their owners are working...
The aim of this paper is to present the development of an innovative experimental reflective pulse oximetry solution targeting wearable health system for daily monitoring purposes. The measurement of two common human physiological indicators is performed, which are the pulse rate and the blood oxygenation level (SpO2). The design options are detailed, covering photoplethysmographic (PPG) signals sensing...
Photoplethysmography (PPG) sensors are an inexpensive yet cost-effective way to track data correlated to the heart pulsation. The information is acquired with light signals generated by means of a photodiode and by detecting the amount of reflected or transmitted light through the tissue. In this paper, a novel methodology that enables a systematic approach for evaluating high compact signal processing...
This paper explores different modelling techniques for representing electrochemical energy storage devices in insular power grid applications. Particular attention is given to Thevenin based and not Thevenin based models. A case study involving two insular power systems with renewable generation are used to stand out the performance of the selected battery technologies: Lithium-ion (Li-ion), Nickel-Cadmium...
The constant increment in the penetration of renewable energy sources requires the improvement of the flexibility of the power system. Due to its high generation cost, it is expected that insular power systems experience an important increment in the power generation from renewable energy sources and, under this perspective, an energy storage system (ESS) could be the key factor to meet this goal...
In this paper a probabilistic model to solve the economic dispatch (ED) problem considering the uncertainty introduced by power sources, such as wind and solar, is presented. Assuming the forecasting error to be modeled by a beta probability distribution function (PDF), the proposed methodology presented in this paper allows the incorporation of this PDF in the optimization model, obtaining the PDF...
Due to increasing integration of renewable generation into the electrical framework in last decades, the mathematical techniques required for the optimal day-ahead scheduling needs to be continuously improved, specifically for modeling the variability of these sources. In this paper, a method for producing a new solution for the stochastic unit commitment (UC) problem from the analysis of each scenario...
Smart home vision aims for the integration of key electrical appliances and services, communications and information technologies into one intelligent network to be controlled, monitored and managed by the building user. A wireless infrastructure as a smart home communication backbone is the logical choice for a so high level of integration. This paper updates on wireless communication technologies...
In this paper, a management strategy to be used in the scheduling of insular electrical systems with energy storage system (EES) is presented. Integration of ESS allows reducing generation costs and greenhouse gases (GHG) emissions, as well as improving wind power penetration levels. The methodology presented in this paper is particularly useful for those systems provided with battery ESS, due to...
The main problem in integration of renewable power sources to the electricity grid is the uncertainty introduced by the power forecasting process in the optimal scheduling problem, which can considerably increase the generation cost. This problem has been widely analyzed using scenario generation/reduction methodologies. However, the consideration of a reduced number of scenarios can limit the capabilities...
This paper presents a review of short-term hydro scheduling tools reported by the scientific community, presenting different methodologies and models published over the last 20 years about operations, scheduling and optimization of hydro systems, in competitive electricity markets, considering the short-term horizon, i.e., between one day and one week, with the goal of maximizing profits and reducing...
The use of biomass as energy source becomes considered again as a possibility, after a period in which practically felt in disuse, especially in industrial environments. Nowadays it is again an important alternative, mainly due to the increasing prices of fossil fuels, especially oil and natural gas, as well as by the growing environmental and sustainability concerns, since the biomass fuel is considered...
In the future smart grid the consumer will play an important contribution to the quality of the electricity transmission and delivery and to the reduction of the grid carbon dioxide emissions, by applying a conscious behaviour to their energy consumption. But, to be able to accomplish that, the consumers need to know and control their activity so they can act upon the available information. Several...
The current grid must be updated and controlled with automated systems that offer the intelligence of the smart grid. In this task the wireless networks for sensors and actuators are very important component of the future grid infrastructure, being the “nerve cells” of the entire system. The most important player in the smart grid is probably the consumer, that can use the electricity and at the same...
This paper present a novel hybrid approach based on a combination of wavelet transform (WT), evolutionary particle swarm optimization (EPSO) and adaptive-network-based inference system (ANFIS), for short-term wind power forecasting in Portugal. The accuracy of the wind power forecasting attained with the proposed approach is evaluated, reporting its proficiency from a real-world case study in comparison...
The implementation of a renewed electrical grid is urgent and it must be flexible, reliable, efficient and manageable. In this context, sensors and actuators play an important part, thus being the “nerve cells” of the grid. The ZigBee standard is receiving an increased acceptance by the industry and is experiencing a fast implementation. Hence, several new field tests are presented in this paper in...
The wind power generation is experiencing a rapid growth, achieving the highest number of European installations in 2010 comparing to other renewable sources. The need for a smarter grid capable of integrating several decentralized sources of energy and the increasing need for energy in urban areas, has led to an increase interest in wind turbines for the urban areas. In these environments, vertical...
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