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"This book presents the readers with the modeling, functioning and implementation of solar hydrogen energy systems, which efficiently combine different technologies to convert, store and use renewable energy. Sources like solar photovoltaic or wind, technologies like electrolysis, fuel cells, traditional and advanced hydrogen storage are discussed and evaluated together with system management and output performance. Examples are also given to show how these systems are capable of providing energy independence from fossil fuels in real life settings."

"Expert techniques for extracting hydrogen from water using transition metal oxides as catalysts Solar Hydrogen Generation details the complex process of separating hydrogen from oxygen--photoelectrolysis. This book comprehensively covers the chemical characteristics of transition metal oxides, explaining how to covert solar energy to electron energy through transition metal oxides. Past experimentations and future directions are discussed. Solar Hydrogen Generation Comprehensively reviews physical characteristics of transition metal oxides both in electrochemical and photocatalytic applications Includes history and future prospects for water photoelectrolysis Reviews state-of-the-art achievements in the fields of condensed matter physics, nanostructured material science, electrochemistry, and photocatalysis Addresses potential problems and solutions In-depth coverage: Hydrogen Production; Electrochemistry and Photoelectrolysis; Transition Metal Oxides; Molecular Structure, Crystal Structure, and Electronic Structure; Optical Properties and Light Absorption; Bandgap, Band Edge, and Engineering; Impurity, Dopants, and Defects; Photocatalytic Reactions, Oxidation and Reduction; Organic and Inorganic Systems; Surface and Interface Chemistry; Nanostructured and Morphology; Synchrotron Radiation and Soft X-Ray Spectroscopy"--Provided by publisher."This pioneering guide covers one of the most promising sustainable energy carriers--water hydrogen--and shows how to extract hydrogen from water using transition metal oxides as catalyst."

"This book about describes the principles and materials challenges for the conversion of sunlight into hydrogen through water splitting at a semiconducting electrode. Readers will find an analysis of the solid state properties and materials requirements for semiconducting photo-electrodes, a detailed description of the semiconductor/electrolyte interface, in addition to the photo-electrochemical (PEC) cell. Experimental techniques to investigate both materials and PEC device performance are outlined, followed by an overview of the current state-of-the-art in PEC materials and devices, and combinatorial approaches towards the development of new materials. Finally, the economic and business perspectives of PEC devices are discussed, and promising future directions indicated."

"The effect of metal doping on the hydrogen physisorption energy of a single walled carbon nanotube (SWCNT) is investigated. Unlike many previous studies that treated metal doping as an ionic or charged element, in this study, lithium and magnesium are doped to an SWCNT as a neutral charged by substituting boron on the SWCNT (Boron substituted SWCNT). Using ab initio electronic structure calculations, the interaction potential energies between hydrogen molecules and adsorbent materials were obtained. The potential energies were then represented in an equation of potential parameters as a function of SWCNT diameters in order to obtain the most precise potential interaction model. Molecular dynamics simulations were performed on a canonical ensemble to analyze hydrogen gas adsorption on the inner and outer surfaces of the SWCNT. The isosteric heat of the physical hydrogen adsorption on the SWCNT was estimated to be 1.6 kcal/mole, decreasing to 0.2 kcal/mole in a saturated surface condition. The hydrogen physisorption energy on SWCNT can be improved by doping lithium and magnesium on Boron substituted SWCNT. Lithium-Boron substituted SWCNT system had a higher energy physisorption that was 3.576 kcal/mole compared with SWCNT 1.057–1.142 kcal/mole. Magnesium-Boron substituted SWCNT system had the highest physisorption energy that was 7.396 kcal/mole. However, since Magnesium-Boron substituted SWCNT system had a heavier adsorbent mass, its physisorption capacity at ambient temperature and a pressure of 120 atm only increased from 1.77 wt% for the undoped SWCNT to 2.812 wt%, while Lithium-Boron substituted SWCNT system reached 4.086 wt%."

"Ketergantungan pada bahan bakar fosil konvensional sepanjang perkembangan peradaban modern telah menyebabkan dunia mengalami krisis energi dan lingkungan. Di antara semua sumber daya energi alternatif, oil shale adalah yang paling menjanjikan dengan cadangannya yang melimpah secara global. Mengenai masalah lingkungan, hidrogen adalah medium pembawa energi terbersih dan paling menjanjikan, kandidat sempurna untuk mengurangi emisi karbon. Memproduksi hidrogen menggunakan oil shale sebagai bahan baku mungkin menjadi solusi terbaik untuk masalah energi dan lingkungan dunia. Dalam makalah penelitian ini energi dan emisi (CO2) dari sistem kilang oil shale akan dievaluasi. Ada dua skenario produksi hidrogen yang akan disimulasikan, dievaluasi, dan dibandingkan satu sama lain. Skenario pertama adalah sistem kilang oil shale konvensional di mana hidrogen diproduksi dan digunakan untuk meningkatkan kualitas shale oil menjadi HVHF’s. Skenario kedua adalah sistem kilang oil shale baru di mana oil shale diubah menjadi hidrogen sepenuhnya sebagai produk tunggal. Berdasarkan analisis massa, sistem baru meningkatkan efisiensi konversi keseluruhan sebesar 9,27% dibandingkan dengan sistem konvensional. Berdasarkan analisis energi, sistem baru menururnkan efisiensi energi keseluruhan sebesar 2,37% dibandingkan dengan sistem konvensional. Berdasarkan analisis emisi, meskipun sistem baru meningkatkan emisi karbon keseluruhan sebesar 55%, sistem ini memiliki sistem yang lebih baik untuk menghasilkan lebih banyak hidrogen dengan rasio emisi karbon yang lebih sedikit dibandingkan dengan sistem konvensional.

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Dependency on conventional fossil fuels throughout the development of modern civilization has caused the world into energy and environmental crisis. Among all alternative energy resources, oil shale is the most promising with its globally abundant reserves. Concerning environmental issues, hydrogen is the cleanest and promising energy carrier, a perfect candidate to reduce toxic emissions of energy. Producing hydrogen using oil shale as feed might be the ultimate solution for both energy and environmental issues of the world. In this research paper, the energy and emission (CO2) of the oil shale refinery system will be evaluated. There are two scenarios of hydrogen production that will be simulated, evaluated, and compared to each other. The first one is the conventional oil shale refinery system where hydrogen is produced and used to upgrade the quality of shale oil into HVHF’s. The second one is the novel oil shale refinery system where oil shale is converted into hydrogen completely as the single product. Based on the mass analysis, the novel system increases the overall conversion efficiency compared to the conventional system by 9,27%. Based on the energy analysis, the novel system decreases the energy efficiency compared to the conventional system by 2,37%. Based on the emission analysis, although the novel system increases the overall carbon emission by 55%, it has a better system for producing more hydrogen with less carbon emission ratio compared to the conventional system."

"Pengembangan terhadap energi hidrogen tengah tumbuh pesat belakangan ini karena sumber energi hijau menjadi jauh lebih penting di berbagai industri dan mampu menggantikan natural gas dimasa mendatang. Negara - negara di berbagai belahan dunia telah mulai mengembangkan energi hidrogen secara masif seperti Jepang, Korea, Italia, Spanyol, Arab Saudi, Cina, Turki dan Maroko dengan metoda elektrolisis dari sumber energi terbarukan dengan biaya produksi yang cukup kompetitif. Biaya produksi hidrogen yang telah dikembangkan dengan metoda elektrolisis ini di Turki USD 3,1 $/kgH2, Korea Selatan USD 7,72 $/kgH2, Italy 6,9 €/kgH2, Arab Saudi 43,1 $/kgH2 dan Maroko 4,99 $/kgH2. Oleh karena itu, diperlukan penelitian pengembangan produksi green hydrogen di Indonesia dengan metoda elektrolisis dari floating solar photovoltaic di Waduk Cirata. Metoda penelitian dimulai dengan pemilihan teknologi green hydrogen plant dengan membandingkan spesifikasi elektroliser yang tersedia dipasaran melalui skema “scoring”. Selanjutnya dilakukan analisa keekonomian melalui tiga skema excess power yaitu 20%, 30% dan 40% dari energi listrik yang tersedia pada floating solar photovoltaic. Analisa keekonomian dilakukan dengan menghitung nilai Net Present Value (NPV), Internal Rate Return (IRR) dan Payback Period. Teknologi yang dipilih berdasarkan hasil scoring adalah PEM Electroliser dengan nilai scoring 8,32. Analisa keekonomian pengembangan green hydrogen plant yang paling optimum adalah skema excess power 40% dengan nilai NPV sebesar USD 74.152.302, IRR 18,92% dan Payback Period selama 4,76 tahun (4 tahun 10 bulan).

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The development of hydrogen energy is growing rapidly in recent years as green energy sources have become much more important in various industries and can replace natural gas in the future. Countries in various parts of the world have started to develop hydrogen energy massively such as Japan, Korea, Italy, Spain, Saudi Arabia, China, Turkey and Morocco by using electrolysis method to produce hydrogen from renewable energy sources with competitive production costs. The cost of producing hydrogen which has been developed by the electrolysis method in Turkey USD 3.1 $/kgH2, South Korea USD 7.72 $/kgH2, Italy 6.9 €/kgH2, Saudi Arabia 43.1 $/kgH2 and Morocco 4.99 $/ kgH2. Therefore, it is necessary to research the development of green hydrogen production in Indonesia using the electrolysis method from floating solar photovoltaic in the Cirata Reservoir. The research method was carried out by selecting green hydrogen plant technology by comparing the specifications of the electrolyzer available in the market through a "scoring" scheme. Furthermore, an economic analysis is carried out through three excess power schemes, namely 20%, 30% and 40% of the electrical energy available in floating solar photovoltaic. Economic analysis is done by calculating the value of Net Present Value (NPV), Internal Rate Return (IRR) and Payback Period. The technology chosen based on the scoring results is PEM Electroliser with a scoring value of 8.32. The most optimum economic analysis of green hydrogen plant development is the 40% excess power scheme with an NPV value of USD 74,152,302, IRR 18.92% and a Payback Period of 4.76 years (4 years 10 months)."