Search results for "hydrogen"

Nanostructured Ni-Co Alloy Electrodes Fabrication and Characterization for both Hydrogen and Oxygen Evolution Reaction in Alkaline Electrolyzer

2019

Sun and wind as power sources are becoming more and more relevant owing to the progressive abandoning of the fossil fuels [1,2]. Additionally, worldwide public authorities are encouraging the use of renewable energies by promoting laws and guidelines [3,4]. In this scenario, a fundamental role can play hydrogen that besides being a valuable energy carrier, it can also act as a storage medium to balance the discontinuity affecting the renewable energy sources production [5]. As a consequence, cheap and abundant availability of hydrogen is crucial. Electrochemical water splitting is likely one of the most valuable technique to produce hydrogen because the process is environmentally friendly b…

NANOSTRUCTURED ELECTRODES FOR HYDROGEN PRODUCTION IN ALKALINE ELECTROLYZER

Wearable sensor for real-time monitoring of oxidative stress

Optimization of Electrodeposited Nickel-Zinc Alloys for Alkaline Electrolyzer with Nanostructured Electrodes

It is common opinion that hydrogen will become increasingly important over time. However, many research efforts still need to be made to develop efficient, low-cost and carbon-free hydrogen production. In this context, electrolysers will play a key role, but it is necessary to develop efficient and low-cost electrode/electrocatalyst materials. In this work, Nickel-Zinc alloy electrodes with nanowires morphology were investigated as cathode for alkaline electrolyzer. Electrodes were obtained by the simple method of template electrosynthesis that is also inexpensive and scalable. Nanostructured electrodes were analysed by morphological and chemical analyses. The nanowires composition is depen…

Pd-Co-Based Electrodes for Hydrogen Production by Water Splitting in Acidic Media

2023

To realize the benefits of a hydrogen economy, hydrogen must be produced cleanly, efficiently and affordably from renewable resources and, preferentially, close to the end-users. The goal is a sustainable cycle of hydrogen production and use: in the first stage of the cycle, hydrogen is produced from renewable resources and then used to feed a fuel cell. This cycle produces no pollution and no greenhouse gases. In this context, the development of electrolyzers producing high-purity hydrogen with a high efficiency and low cost is of great importance. Electrode materials play a fundamental role in influencing electrolyzer performances; consequently, in recent years considerable efforts have b…

Performance of a RED system with ammonium hydrogen carbonate solutions

2016

The use of closed-loop salinity gradient power (SGP) technologies has been recently presented as a viable option to generate power using low-grade heat, by coupling a SGP unit with a thermally-driven regeneration process in a closed loop where artificial solutions can be adopted for the conversion of heat into power. Among these, the closed-loop reverse electrodialysis (RED) process presents a number of advantages such as the direct production of electricity, the extreme flexibility in operating conditions and the recently demonstrated large potentials for industrial scale-up. Ammonium hydrogen carbonate (NH4HCO3) is a salt suitable for such closed-loop RED process thanks to its particular …

Reverse electrodialysis with NH4HCO3-water systems for heat-to-power conversion

2017

Abstract A Reverse ElectroDialysis Heat Engine (REDHE) system operating with “thermolytic” ammonium hydrogen-carbonate (NH4HCO3) aqueous solutions as working fluids is studied. The engine is constituted by (i) a RED unit to produce electric power by mixing the solutions at different salinity and (ii) a thermally-driven regeneration unit including a stripping and an absorption column to restore the initial salinity gradient thus closing the cycle. In the present work only the RED unit and the stripping column are taken into account. In particular, a simplified integrated process model for the whole cycle was developed: it consists of (i) a lumped parameter model for the RED unit validated wi…

ON THE POTENTIAL IMPACT OF GREEN HYDROGEN FACILITIES ON THE PLANNING OF RES PLANTS IN SICILY

2021

A recent report on climate change and global warming, soil and oceans and the cryosphere [1] highlighted the disastrous effects that would be produced if climate change were not stopped.

Multi-objective Optimization of Energy Hubs at the Crossroad of Three Energy Distribution Networks

2016

This paper provides a multi-objective optimization framework aimed at the management of a multi-carrier energy system involving both electricity and hydrogen. Using the concept of the multi-carrier hub, the proposed system has been modelled in order to define completely every energy flow inside the plant. After that, a heuristic multi-objective optimization algorithm, the Non-dominated Sorting Genetic Algorithm II, has been implemented for the energy management of the plant, taking into account simultaneously three different objective functions related to economic and technical goals. This optimization process provides the set point defining the working configuration of the plant for a dayl…

Life Cycle Energy Consumption and Air Emissions Comparison of Alternative and Conventional Bus Fleets in Vietnam

2022

The study (a) assesses the life cycle energy consumption and air emissions impacts of battery electric buses (e-buses) and conventional buses operated in Vietnam, and (b) compares them with those of hydrogen buses. The results indicate that e-buses and hydrogen buses are preferred options compared to conventional buses in terms of energy consumption, GHG emissions and other air quality impacts over their whole life cycle. Life cycle energy consumption of diesel buses is triple that of e-buses, and is significantly higher than that of hydrogen buses. Replacing conventional buses with e-buses can reduce energy consumption by 50%. For GHG emissions and air quality impacts, the adoption of elec…