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Ammonia has recently gained attention as a potential alternative fuel for gas turbines due to its relatively high energy density and mainly its low environmental impact since there is no CO2 production during the combustion. In this study, we evaluate the integration of a Power to Ammonia to Power process(P2A2P) with a system for power generation and investigate the impact of the use of ammonia in gas turbines from technical, energetic, and environmental points of view. First, the P2A2P system layout is defined and then the scale-up of the process is evaluated to be integrated with a commercial medium-size Gas Turbine. The optimization of the size and Balance Of Plant (BOP) of the P2A2P process and the integration with the GT system are evaluated also considering the impact on the GT system. Moreover, a generic radial-tangential swirler representing a first design attempt to study the retrofittability of a natural gas-designed combustion chamber to operate with an NH3-H2 fuel blend is investigated. The results from dedicated experimental tests and the corresponding CFD simulations are discussed with a strong focus on the NOx pollutant emission representing one of the main limiting factors for ammonia as fuel.

This paper aims to present a thermo-economic approach for methanol production comparing different renewable energy sources. In this study, the methanol is produced from the CO 2 hydrogenation in a pressurized reactor; two different plant configurations are analyzed: in the first carbon dioxide is obtained from biogas upgrade, while in the second one CO 2 is acquired from external sources. Carbon dioxide is mixed with hydrogen and then the gas is sent into the reactor for methanol synthesis. Hydrogen is produced by an alkaline pressurized electrolyzer (1 MW, 30 bar) fed by time-dependent electrical energy produced by renewable plants (hydroelectric, wind or photovoltaic), when available; in the remaining periods, electricity is purchased by the national grid. Since the available electrical energy from the different renewable sources is not constant throughout the year, a time-dependent hierarchical thermo-economic analysis is performed in order to investigate the best plant configuration. The analyses are performed with the W-ECoMP simulation tool (developed by the authors' research group) considering different costs of electricity and different methanol selling prices taking into account the future market forecast. The results for the two plant lay-outs are compared from energetic, economic and environmental point of view for the different renewable energy sources to evaluate the best solution in the Italian scenario. [ABSTRACT FROM AUTHOR]

This paper aims to investigate a system for large size hydrogen production, storage and distribution to refueling stations for its employment in land transportation. Hydrogen is produced by pressurized alkaline electrolysers, employing time-dependent renewable electricity produced by a large size hydroelectric plant (100 MW); the hydrogen is stored into pressurized tanks and delivered by trucks to the refueling stations. Since the technologies related to hydrogen vehicles still present high costs, an alternative solution is investigated: the hydrogen produced by water electrolysis is converted into Hydro-methane (a blend of methane and hydrogen, where H 2 maximum volume content is 30%), which is easier to be stored and transported to the refueling stations, considering its higher energy content in volume terms. Since electricity available from the hydroelectric plant varies widely throughout the year, a time-dependent hierarchical thermo-economic analysis is performed in order to investigate both the optimal size of the whole plant and the management of the alkaline electrolysers. The analysis is carried out for the H 2 and Hydro-methane plant lay-outs, comparing the results from energetic, strategic and economic point of view in a typical European economic scenario (Italy). For the different plant lay-outs, two energy scenarios are considered: (i) to feed the electrolysers only with renewable hydroelectricity during the year, keeping them off when it is not available; (ii) to purchase electricity from the national grid in shortage periods, in order to increase the utilization factor of the electrolysers and the production of H 2 and Hydro-methane for the refueling stations. [ABSTRACT FROM AUTHOR]

New policies and strict emission limits in the transports sector result in a gradual switch towards alternative fuels and hydrogen is getting attention: fuel cell systems are considered ideal energy converters of the next future. As the interest is rising in Proton Exchange Membrane Fuel Cells (PEMFC), there is a need for experimental research and dedicated laboratories on systems designed with Balance of Plant. In this context, the HI-SEA Laboratory (240-kW PEMFC by Nuvera FC, a joint between the University of Genoa-Fincantieri) was born. In this paper, the tuning of the laboratory to simulate a ship-likely environment is addressed, looking at the main problematics and resolutions, related to the cathodic line and the cooling control. Some guidelines are defined to install a PEMFC system onboard a ship exploiting the existing infrastructure. Thanks to the experimental campaign, a stack voltage model previously validated is employed to evaluate the performance of the system. • Tuning of 240 kW PEMFC integrated system and lesson-learned. • Balance of Plant of FC system simulates shipping environment. • Identification and resolution of cooling and cathodic lines issues. • Performance evaluation of experimental data through PEMFC model application. • Identification of management procedure for performance optimization. [ABSTRACT FROM AUTHOR]

Background: Brain-Derived Neurotrophic Factor (BDNF) is a neurotrophin which plays survival- and growth-promoting activity in neuronal cells and it is involved in cellular plasticity mechanisms as it controls activity dependent synaptic transmission. A functional polymorphism (Val66Met) in the pro-region of BDNF, which affects the intracellular trafficking of proBDNF has been associated with memory and cognitive deficits as well as to an increased susceptibility for several psychiatric disorders especially those with a neurodevelopmental origin. To date, no study has evaluated the influence of the Val66Met polymorphism on BDNF levels in a peripheral system that may reflect fetal neurodevelopment. Therefore we investigated in amniotic fluids (AF) obtained from 139 healthy women during 15-17 week of pregnancy, BDNF protein levels in correlation with the Val66Met polymorphism.Results: Interestingly we found a significant BDNF protein levels reduction in 55 Met carriers (Val/Met and Met/Met) (p = 0.002) as compared to 84 non carriers (Val/Val), and no effect of fetus gender, maternal age or gestation week on BDNF levels has been observed.Conclusion: These results, although explorative, indicate that during fetal life the Val66Met genotype might influences BDNF protein levels in AF supporting the involvement of this polymorphism in behavioral and functional brain individual differences in the adulthood. [ABSTRACT FROM AUTHOR]