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Abstract: From the energy point of view, the season we have been living more and more seems the era of sources diversification. The most correct scenario for a sustainable energy future foresees no predominance of one source over the others in any area of the world but a proper energy mix, based on locally available resources and needs. The concept and role of energy vectors is key: “(an energy vector) allows transfer, in space and time, a given quantity of energy, hence making it available for use distantly in time and space from the point of availability of the original source”. Therefore, a scenario that gives full scope for the ES to be immune from the characteristics of non-sustainable resource consumption and waste production, the system itself must shift the focus from resources to vectors (mainly electricity, hydrogen, heat). Smart grids have been largely indicate, in this context, as an answer for their characteristic “needful design” to move from the “old” grids (unidirectional power flows) to “new” bi-directional electricity networks. This is not enough: the real need is for an intelligent management of a complete set of energy sources and vectors, as electricity, heat, hydrogen, bio and non-biofuels, that requires a clear shift that goes beyond smart grids and looks at Intelligent Energy Networks. [Copyright &y& Elsevier]

Abstract: The crucial mission of energy research is the promotion and implementation of methods, technologies and processes for a sustainable economic and social development. Within this framework the key progress energy systems is the realization of Closed Cycles of Energy Resources—CCER, whose goal is to achieve zero consumption in terms of non-renewable resources and no impact on the environment. A CCER can be realised with biomass, a renewable energy resource, and hydrogen, the “cleanest” fuel. This solution can supply secure and environmental friendly energy for medium electric and heating power demand. This context meets the actual trend towards cleaner, greener, smaller and more decentralized energy production facilities. The paper, after a brief description of closed hydrogen cycle and biomass resources, presents a comprehensive overview of the topic. The review of sustainability of biomass hydrogen systems shows how these systems, even if they require further research and demonstration activity, can obtain a remarkable electricity and heat production with near “zero” pollution. Furthermore, using refusals or “trash” materials and “standard” technologies, the biomass to hydrogen systems can provide in many case economic and social advantages. [Copyright &y& Elsevier]

Abstract: The realisation of energy systems that do not consume resources and do not produce waste is the new challenge of energy research. This kind of energy systems are to be based on what we call Closed cycles of energy resources. The realisation of Closed cycles of resources can be achieved in the energy sector by exploiting renewable resources and structurally integrating energy vectors in the energy system. So the inclusion of energy vectors (to be produced from several primary resources) in the energy system chain becomes a key concept of the entire human development model. In this new scenario, the opportunity of using hydrogen shows all its interest. Hydrogen, electricity and other energy vectors, in a large scale application, allow to fully satisfy all the final uses of energy that the human society needs for its social and economical development. Energy vectors like electricity, heat exchanging fluids, and “producible” fuels—as hydrogen—are the key for entering a new energy era. What many call “hydrogen era” is in effect “the era of energy vectors”. [Copyright &y& Elsevier]

Assessing the energy performances of a vehicle on the road requires collecting large data samples to ensure repeatability of the measurements despite the many variables which influence them. This paper proposes a method to dimension the campaign and compares various campaigns despite differences in the influencing variables through statistical analysis. This methodology has been applied to the Italian testing campaign of Toyota Yaris Hybrid 2020. The results are compared to those collected in a similar campaign for the previous model. The pandemic of COVID-19 forced the acquisitions to be made in months in which the weather and the traffic were different, and the reduced mobility lowered the traffic intensity. The proposed method was able to make the campaigns comparable besides the differences. It can also be applied to design future campaigns to reduce the quantity of collected data while maintaining the same statistical significance. The newest model of Toyota Yaris Hybrid performs better than the previous one, and it was analysed how. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an analysis of the data collected during a test of the 36 kW alkaline electrolyser at West Bacon Farm (WBF), Loughborough, UK. This data is then used to verify a software model of an electrolyser. The test consisted of collecting data under different operating conditions, in particular controlling the power supplied to the electrolyser. The experiment was divided in four phases. In the first two phases, the electrolyser was operated at full power, in the third phase it was operated at 60% of maximum power and in the forth it was operated at 20% of maximum power, which is the minimum permitted level. Each phase lasted approximately an hour. During phase 1, the initial warm up period, the voltage remained almost constant, while the current increased to a maximum of 428 A. After about an hour, the current suddenly dropped to 310 A, the voltage decreased from 92 V to 88 V and hydrogen production decreased from 7.3 Nm3/h to 6.6 Nm3/h, even though no change had been made to the control parameters, which were still set to maximum power input. The temperature continued upwards with only a slight reduction in its rate of increase and the pressure stopped rising, remaining at 22 bar(g). This point marks the transition from phase 1 to phase 2 and the reasons for the sudden discontinuity are investigated in this study. Once the optimum operating temperature was reached, during phase 2, it was maintained within a limited range by the cooling system. The initial stack temperature, at the beginning of phase 1, had been 17 °C. The net power draw increased until the stack temperature reached its maximum at 76 °C after about 1 h 20 min. [Copyright &y& Elsevier]

Abstract: This paper reports the preliminary experimental evaluation of a four wheel motors series hybrid prototype equipped with an internal combustion engine coupled to a generator and an energy recovery system (batteries plus ultracapacitors). The paper analyses global efficiency (energy dissipated to overcome the dissipative forces on energy dissipated in fuel), autonomy in electric configuration, and the efficiency of the regenerative braking system. The tests were carried out in a test cell equipped with a chassis dynamometer. The tests were performed according to the current regulated procedures. A constant speed test was performed in order to evaluate the autonomy of the vehicle in the electric configuration. The results show that the real tank to wheels efficiency is about 30% for HOST as a series hybrid and 79% for HOST as an electric vehicle. [ABSTRACT FROM AUTHOR]