Review Article

Hydrogen production for energy: An overview



Power to hydrogen is a promising solution for storing variable Renewable Energy (RE) to achieve a 100% renewable and sustainable hydrogen economy. The hydrogen-based energy system (energy to hydrogen to energy) comprises four main stages; production, storage, safety and utilisation. The hydrogen-based energy system is presented as four corners (stages) of a square shaped integrated whole to demonstrate the interconnection and interdependency of these main stages. The hydrogen production pathway and specific technology selection are dependent on the type of energy and feedstock available as well as the end-use purity required. Hence, purification technologies are included in the production pathways for system integration, energy storage, utilisation or RE export. Hydrogen production pathways and associated technologies are reviewed in this paper for their interconnection and interdependence on the other corners of the hydrogen square.

Despite hydrogen being zero-carbon-emission energy at the end-use point, it depends on the cleanness of the production pathway and the energy used to produce it. Thus, the guarantee of hydrogen origin is essential to consider hydrogen as clean energy. An innovative model is introduced as a hydrogen cleanness index coding for further investigation and development.

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Smart Hydrogen Stars Poster

Innovative Hydrogen Energy Integrated System


An innovative Renewable Hydrogen system Has been developed to solve today’s main challenge in developing residential or industrial stand-alone settlements in remote areas. Clean energy of zero life cycle emissions is urgently needed to keep the global warming under control. An Energy-Water-Waste nexus approach with smart stand-alone microgrid is techno-economically viable solution to reduce cost of energy and eliminate emissions.

H2E Group designed and evaluated a 100% renewable energy integrated model for a stand-alone hybrid microgrid where Hydrogen is the backbone for energy storage and distribution. A module of a hybrid PV-Battery-Hydrogen system to serve one hundred dwelling (400-500 dwellers) with 2MWh of daily average energy demand has been modelled and simulated in comparison with conventional use of Diesel fueled energy generation. Water is generated by solar desalination and condensation from the humid atmospheric air. A bio-waste and waste-water recycling plant is an essential additive to reduce the environmental impact and save water as well as to generate power and gas. The energy model techno-economic simulation shows a considerable reduction in the cost of energy by 15 - 25% and eliminate 1.39 ton CO2 per capita per year Carbon emissions (total of 693 tons of CO2/year). The project can achieve a payback in Five and a half (5.5) years depending on Diesel costs and an effective Carbon Tax. The proposed project is a holistic solution for the trilemma of emissions, pollution and sustainability challenges and the Modular design can be replicated. This project can create energized autarky smart cities in the isolated and remote areas  generate its electricity, gas and water supply from 100% renewable resources. This will make Sharjah Global Hydrogen Energy Hub as well as overcoming the national policy barriers and change the decision makers perception for a 100% renewable energy.