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Browsing by Issue Date, starting with "2022-05-10"

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  • Photovoltaic integrated electric vehicles: assessment of synergies between solar energy, vehicle types and usage patterns
    Publication . Sagaria, Shemin; Duarte, Gonçalo; Neves, Diana; Baptista, Patrícia
    Electric vehicles are promoting sustainable developments in the automotive industry. But the short driving range has been an inconvenience to the electric vehicle (EV) users. This paper evaluates the potential of Photovoltaic integrated into EV in real-world conditions to assess energy consumption, range and EV's charging frequency for battery and fuel cell powertrain configurations. A simulation model is developed, which estimates the energy production through onboard Photovoltaics, energy consumption, and range under diverse driving profiles for five different vehicle types, ranging from Micro-car, 5 seaters light-duty vehicle, Shuttle and heavy-duty vehicles. The results showed that the range increased with reduced energy consumption and charging frequency with onboard Photovoltaics for battery powertrain configuration. The range improved by 30-50% for Microcar and 30-100% for the 5-seater vehicle with the private driving profile. Simultaneously, for Shuttle, an increase in the range between 5 and 15% is reported. On the contrary, the results indicated the fuel cell powertrain configuration does not present an added value with onboard Photovoltaics. Further analysis showed that the higher irradiance rates improved the operational period of Photovoltaic integrated into EV by 5 more days than standard EV. Finally, the economic analysis revealed that Photovoltaics integrated into EV is profitable, reaching the break-even point on the additional photovoltaics expense before the half-life of the vehicle, which makes the total ownership cost lower than a standard EV for its lifetime.
    2022-05-10Journal article Restricted access Show more
  • On the real experimentation and simulation models for millimeter-wave
    Publication . Figueiredo, Alexandre; Ferreira, Tânia; Raposo, Duarte; Luís, Miguel; Rito, Pedro; Sargento, Susana
    The emergence of millimeter-wave based technologies is pushing the deployment of the 5th generation of mobile communications (5G), on the potential to achieve multi-gigabit and low-latency wireless links. Part of this breakthrough was only possible with the introduction of small antenna arrays, capable to form highly directional and electronically steerable beams. This strategy allowed the overcoming of some drawbacks, but with a higher price: the re-design of the lower layers by introducing beamforming techniques. The impact of these changes is not well studied on the higher layers, in the most recent stacks (IEEE 802.11ad, 3GPP). Thus, the study of real deployments and the use of accurate network simulators play a key role, by enabling the test of complex large-scale scenarios. This article presents a key component missing in the simulation of mmWave networks, a blockage model. To the best of our knowledge, this is first blockage model that emulates the effects of obstacles in the mmWave links. Additionally, a codebook generation of a phased antenna array, with the Quasi-Deterministic (Q-D) channel model is also presented. All models are tested and compared with an outdoor mmWave network using the IEEE 802.11ad standard. The simulated and the real-life tests show similar results, with an average error for the worst case of 2.43% (index ranges) and 4.51% (distance), and to an average standard deviation of about 1.33 dBm and 2.26 dBm.
    2022-05-10Journal article Open access Show more