Zeitschriftenartikel: „Green hydrogen energy systems“

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Karakoc, Hikmet, Adnan Midilli und Onder Turan. „Green hydrogen and fuel cell systems“. International Journal of Energy Research 37, Nr. 10 (10.07.2013): 1141. http://dx.doi.org/10.1002/er.3037.

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Aziz, Muhammad. „Advanced Green Technologies Toward Future Sustainable Energy Systems“. Indonesian Journal of Science and Technology 4, Nr. 1 (07.03.2019): 89. http://dx.doi.org/10.17509/ijost.v4i1.15805.

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Currently, the usable energy is basically harvested from the fossil energy sources, including coal, oil, and gas, which are believed to harm the environment due to the emitted GHGs. The awareness to the climate change and limited reserve of fossil energy sources has led to a strong motivation to develop a new energy system which can facilitate three important pillars: security, clean environment, and economic opportunity. This future energy system is strongly expected to be able to blend both fossil and renewable energy sources, while minimize its environmental impacts. To realize it, the primary energy sources are converted to the efficient secondary energy sources, including electricity and hydrogen. These two kinds of secondary energy source are considered very promising in the future, following a high demand in many sectors. In transportation sector, both electricity and hydrogen are believed to become the future fuels as the deployment of electric and fuel cell vehicles is increasing rapidly. In this paper, several potential technologies to produce the energy cleanly from primary energy sources are introduced and evaluated. In addition, clean and efficient technologies in storage and utilization are also described.

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Jorschick, H., P. Preuster, A. Bösmann und P. Wasserscheid. „Hydrogenation of aromatic and heteroaromatic compounds – a key process for future logistics of green hydrogen using liquid organic hydrogen carrier systems“. Sustainable Energy & Fuels 5, Nr. 5 (2021): 1311–46. http://dx.doi.org/10.1039/d0se01369b.

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Dagdougui, Hanane, Ahmed Ouammi und Roberto Sacile. „Modelling and control of hydrogen and energy flows in a network of green hydrogen refuelling stations powered by mixed renewable energy systems“. International Journal of Hydrogen Energy 37, Nr. 6 (März 2012): 5360–71. http://dx.doi.org/10.1016/j.ijhydene.2011.07.096.

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Peksen, Murat. „Hydrogen Technology towards the Solution of Environment-Friendly New Energy Vehicles“. Energies 14, Nr. 16 (10.08.2021): 4892. http://dx.doi.org/10.3390/en14164892.

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The popularity of climate neutral new energy vehicles for reduced emissions and improved air quality has been raising great attention for many years. World-wide, a strong commitment continues to drive the demand for zero-emission through alternative energy sources and propulsion systems. Despite the fact that 71.27% of hydrogen is produced from natural gas, green hydrogen is a promising clean way to contribute to and maintain a climate neutral ecosystem. Thereby, reaching CO2 targets for 2030 and beyond requires cross-sectoral changes. However, the strong motivation of governments for climate neutrality is challenging many sectors. One of them is the transport sector, as it is challenged to find viable all-in solutions that satisfy social, economic, and sustainable requirements. Currently, the use of new energy vehicles operating on green sustainable hydrogen technologies, such as batteries or fuel cells, has been the focus for reducing the mobility induced emissions. In Europe, 50% of the total emissions result from mobility. The following article reviews the background, ongoing challenges and potentials of new energy vehicles towards the development of an environmentally friendly hydrogen economy. A change management process mindset has been adapted to discuss the key scientific and commercial challenges for a successful transition.

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Matani, Behnoosh, Babak Shirazi und Javad Soltanzadeh. „F-MaMcDm: Sustainable Green-Based Hydrogen Production Technology Roadmap Using Fuzzy Multi-Aspect Multi-Criteria Decision-Making“. International Journal of Innovation and Technology Management 16, Nr. 08 (Dezember 2019): 1950057. http://dx.doi.org/10.1142/s0219877019500573.

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In recent years, with increasing demand for fossil fuels, greenhouse gas emissions, acid rains, and air pollution have increased. These issues have encouraged industries to replace the existing fossil fuel system by the hydrogen energy system which is a clean energy carrier. Replacing hydrogen in the future energy systems needs a dynamic and flexible strategic tool for planning and management. Roadmapping tool is a strategic choice for supporting technology management in long-term planning and under the fast-changing environment in manufacturing technologies. This study tackles a novel methodology that considers the uncertainties and linguistic assessments for developing a green-based hydrogen production technology roadmap considering concurrent multi-layered aspects. The aim of this paper is to develop a dynamic and flexible technology roadmap using a combination of the classical roadmapping method with a novel fuzzy multi-aspect multi-criteria decision-making approach (F-MaMcDm). This study represents a quantitative paradigm to roadmapping instead of conventional descriptive “when and how” paradigm. The F-MaMcDm classifies sustainable green-based hydrogen production technologies considering four comprehensive aspects (technical, socio-political, environmental and economic) and criteria relevant to the aspects. The results show that biomass gasification is the first technology to be prioritized followed by other green-based hydrogen production technologies in a long time.

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Filimonov, A. G., A. A. Filimonova, N. D. Chichirova und A. A. Chichirov. „Global energy association: new opportunities of hydrogen technologies“. Power engineering: research, equipment, technology 23, Nr. 2 (21.05.2021): 3–13. http://dx.doi.org/10.30724/1998-9903-2021-23-2-3-13.

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PURPOSE. To analyze the prospects of integrating hydrogen technologies into the traditional directions of development of the electric power industry in the world and Russia. To highlight the competitive advantages of Russia in the changing structure of the industry with the transition to" green " hydrogen. METHODS. The analysis of the literature data and the data of the international information exchange is carried out. RESULTS. The most urgent scientific and technical problem of the economy, affecting any practical aspect of human economic activity, is the issue of the availability of energy resources and the impact on the environment. It is now, in the context of the restrictions caused by the COVID-19 pandemic, that the trends of globalization are particularly acute, and the degree of cross-border information communication using digital capabilities has increased many times. CONCLUSION. The transition to a new technological stage of energy supply for our society is more urgent than ever, based on innovative approaches to the creation of intelligently managed global energy systems with their consolidation and, at the same time, decentralization and distribution to local levels of centers, production, consumption and management, increasing the share of small RES, the introduction of new digital solutions, the use of hydrogen technology chains and hybrid systems based on them and other promising energy technologies on an industrial scale.

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Spadaro, Lorenzo, Alessandra Palella und Francesco Arena. „Totally-green Fuels via CO2 Hydrogenation“. Bulletin of Chemical Reaction Engineering & Catalysis 15, Nr. 2 (23.04.2020): 390–404. http://dx.doi.org/10.9767/bcrec.15.2.7168.390-404.

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Hydrogen is the cleanest energy vector among any fuels, nevertheless, many aspects related to its distribution and storage still raise serious questions concerning costs, infrastructure and safety. On this account, the chemical storage of renewable-hydrogen by conversion into green-fuels, such as: methanol, via CO2 hydrogenation assumes a role of primary importance, also in the light of a cost-to-benefit analysis. Therefore, this paper investigates the effects of chemical composition on the structural properties, surface reactivity and catalytic pathway of ternary CuO-ZnO-CeO2 systems, shedding light on the structure-activity relationships. Thus, a series of CuZnCeO2 catalysts, at different CuO/CeO2 ratio (i.e. 0.2-1.2) were performed in the CO2 hydrogenation reactions at 20 bar and 200-300 °C, (GHSV of 4800 STP L∙kg∙cat-1∙h-1). Catalysts were characterized by several techniques including X-ray Diffraction (XRD), N2-physisorption, single-pulse N2O titrations, X-ray Photoelectron Spectroscopy (XPS), and Temperature-programmed Reduction with H2 (H2-TPR). Depending on preparation method, the results clearly diagnostics the occurrence of synergistic structural-electronic effects of cerium oxide on copper activity, with an optimal 0.5 copper-to-cerium content. The rise of CuO loading up to 30% drives to a considerable increase of hydrogenation activity: C2Z1-C catalyst obtains the best catalytic performance, reaching methanol yield value of 12% at 300 °C. Catalyst activity proceeds according to volcano-shaped relationships, in agreement with a dual sites mechanism. Copyright © 2020 BCREC Group. All rights reserved

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Li, Zheng, Yan Qin, Xin Cao, Shaodong Hou und Hexu Sun. „Wind-Solar-Hydrogen Hybrid Energy Control Strategy Considering Delayed Power of Hydrogen Production“. Electrotehnica, Electronica, Automatica 69, Nr. 2 (15.05.2021): 5–12. http://dx.doi.org/10.46904/eea.21.69.2.1108001.

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In order to meet the load demand of power system, BP based on genetic algorithm is applied to the typical daily load forecasting in summer. The demand change of summer load is analysed. Simulation results show the accuracy of the algorithm. In terms of power supply, the reserves of fossil energy are drying up. According to the prediction of authoritative organizations, the world's coal can be mined for 216 years. As a renewable energy, wind power has no carbon emissions compared with traditional fossil energy. At present, it is generally believed that wind energy and solar energy are green power in the full sense, and they are inexhaustible clean power. The model of wind power solar hydrogen hybrid energy system is established. The control strategy of battery power compensation for delayed power of hydrogen production is adopted, and different operation modes are divided. The simulation results show that the system considering the control strategy can well meet the load demand. Battery energy storage system is difficult to respond to short-term peak power fluctuations. Super capacitor is used to suppress it. This paper studies the battery supercapacitor complementary energy storage system and its control strategy. When the line impedance of each generation unit in power grid is not equal, its output reactive power will be affected by the line impedance and distributed unevenly. A droop coefficient selection method of reactive power sharing is proposed. Energy storage device is needed to balance power and maintain DC voltage stability in the DC side of microgrid. Therefore, a new droop control strategy is proposed. By detecting the DC voltage, dynamically translating the droop characteristic curve, adjusting the output power, maintaining the DC voltage in a reasonable range, reducing the capacity of the DC side energy storage device. Photovoltaic grid connected inverter chooses the new droop control strategy.

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Węcel, Daniel, Michał Jurczyk, Wojciech Uchman und Anna Skorek-Osikowska. „Investigation on System for Renewable Electricity Storage in Small Scale Integrating Photovoltaics, Batteries, and Hydrogen Generator“. Energies 13, Nr. 22 (19.11.2020): 6039. http://dx.doi.org/10.3390/en13226039.

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In this article the solution based on hydrogen generation to increase the flexibility of energy storage systems is proposed. Operating characteristics of a hydrogen generator with integrated electrical energy storage and a photovoltaic installation were determined. The key role of the electricity storage in the proposed system was to maintain the highest operating efficiency related to the nominal parameters of the hydrogen generator. The hydrogen generators achieved the highest energy efficiency for the nominal operating point at the highest power output. Lead-acid batteries were used to ensure the optimal operating conditions for the hydrogen generator supplied with renewable energy throughout the day. The proposed system reduces significantly the hydrogen generator nominal power and devices in system operate in such a way to improve their efficiency and durability. The relations between individual components and their constraints were determined. The proposed solution is fully in-line with previously investigated technologies for improving grid stability and can help incorporate renewable energy sources to increase the sustainability of the energy sector and green hydrogen production.

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Ahshan, Razzaqul. „Potential and Economic Analysis of Solar-to-Hydrogen Production in the Sultanate of Oman“. Sustainability 13, Nr. 17 (24.08.2021): 9516. http://dx.doi.org/10.3390/su13179516.

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Hydrogen production using renewable power is becoming an essential pillar for future sustainable energy sector development worldwide. The Sultanate of Oman is presently integrating renewable power generations with a large share of solar photovoltaic (PV) systems. The possibility of using the solar potential of the Sultanate can increase energy security and contribute to the development of the sustainable energy sector not only for the country but also for the international community. This study presents the hydrogen production potential using solar resources available in the Sultanate. About 15 locations throughout the Sultanate are considered to assess the hydrogen production opportunity using a solar PV system. A rank of merit order of the locations for producing hydrogen is identified. It reveals that Thumrait and Marmul are the most suitable locations, whereas Sur is the least qualified. This study also assesses the economic feasibility of hydrogen production, which shows that the levelized cost of hydrogen (LCOH) in the most suitable site, Thumrait, is 6.31 USD/kg. The LCOH in the least convenient location, Sur, is 7.32 USD/kg. Finally, a sensitivity analysis is performed to reveal the most significant influential factor affecting the future’s green hydrogen production cost. The findings indicate that green hydrogen production using solar power in the Sultanate is promising, and the LCOH is consistent with other studies worldwide.

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Castro Garcia, Abraham, Shuo Cheng und Jeffrey S. Cross. „Removing the Bottleneck on Wind Power Potential to Create Liquid Fuels from Locally Available Biomass“. Energies 14, Nr. 12 (14.06.2021): 3536. http://dx.doi.org/10.3390/en14123536.

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In order to reduce global greenhouse gas emissions, renewable energy technologies such as wind power and solar photovoltaic power systems have recently become more widespread. However, Japan as a nation faces high reliance on imported fossil fuels for electricity generation despite having great potential for further renewable energy development. The focus of this study examines untapped geographical locations in Japan’s northern most prefecture, Hokkaido, that possess large wind power potential. The possibility of exploiting this potential for the purpose of producing green hydrogen is explored. In particular, its integration with a year-round conversion of Kraft lignin into bio-oil from nearby paper pulp mills through a near critical water depolymerization process is examined. The proposed bio-oil and aromatic chemical production, as well as the process’ economics are calculated based upon the total available Kraft lignin in Hokkaido, including the magnitude of wind power capacity that would be required for producing the necessary hydrogen for such a large-scale process. Green hydrogen integration with other processes in Japan and in other regions is also discussed. Finally, the potential benefits and challenges are outlined from an energy policy point-of-view.

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Bartolucci, Lorenzo, Stefano Cordiner, Vincenzo Mulone und Stefano Pasquale. „Design of a multi-energy system under different hydrogen deployment scenarios“. E3S Web of Conferences 238 (2021): 02001. http://dx.doi.org/10.1051/e3sconf/202123802001.

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Multi Energy Systems (MES) are effective means to increase Renewable Energy Sources (RES) penetration in the energy system and therefore to move toward a decentralized low-carbon system. Several energy vectors can be integrated together to exploit synergies in a MES framework, such as electricity, heat and hydrogen. The latter is one of the most promising energy carriers to promote widespread use of MES. Predictive management and well-defined sizing methodology are mandatory to achieve maximum performance out of MES. In this study a grid-connected MES consisting of a photovoltaic (PV) plant, a Battery Energy Storage System (BESS) and a Proton Exchange Membrane Fuel Cell (PEMFC) as a programmable Combined Cooling Heat and Power (CCHP) source, is modelled. Natural gas is considered as an alternative fuel to pure hydrogen. Mixed Integer Linear Programming and Genetic Algorithm are used respectively to solve operation and sizing problems. A single-objective optimization approach, including emission factors as optimization constraints, is carried out to find the optimal configuration of the MES. Several future scenarios are studied, considering different percentages of hydrogen in the gas mixture and comparing the techno-economic performance of the system with respect to a pure hydrogen fueling scenario. Results showed that the environmental objective within the design optimization, promote the use of hydrogen, especially in scenarios with high share of green hydrogen.

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Bethoux, Olivier. „Hydrogen Fuel Cell Road Vehicles and Their Infrastructure: An Option towards an Environmentally Friendly Energy Transition“. Energies 13, Nr. 22 (23.11.2020): 6132. http://dx.doi.org/10.3390/en13226132.

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The latest pre-production vehicles on the market show that the major technical challenges posed by integrating a fuel cell system (FCS) within a vehicle—compactness, safety, autonomy, reliability, cold starting—have been met. Regarding the ongoing maturity of fuel cell systems dedicated to road transport, the present article examines the advances still needed to move from a functional but niche product to a mainstream consumer product. It seeks to address difficulties not covered by more traditional innovation approaches. At least in long-distance heavy-duty vehicles, fuel cell vehicles (FCVs) are going to play a key role in the path to zero-emissions in one or two decades. Hence the present study also addresses the structuring elements of the complete chain: the latter includes the production, storage and distribution of hydrogen. Green hydrogen appears to be one of the potential uses of renewable energies. The greener the electricity is, the greater the advantage for hydrogen since it permits to economically store large energy quantities on seasonal rhythms. Moreover, natural hydrogen might also become an economic reality pushing the fuel cell vehicle to be a competitive and environmentally friendly alternative to the battery electric vehicle. Based on its own functional benefits for on board systems, hydrogen in combination with the fuel cell will achieve a large-scale use of hydrogen in road transport, as soon as renewable energies become more widespread. Its market will expand from large driving range and heavy load vehicles.

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Ekhtiari, Ali, Damian Flynn und Eoin Syron. „Investigation of the Multi-Point Injection of Green Hydrogen from Curtailed Renewable Power into a Gas Network“. Energies 13, Nr. 22 (19.11.2020): 6047. http://dx.doi.org/10.3390/en13226047.

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Renewable electricity can be converted into hydrogen via electrolysis also known as power-to-H2 (P2H), which, when injected in the gas network pipelines provides a potential solution for the storage and transport of this green energy. Because of the variable renewable electricity production, the electricity end-user’s demand for “power when required”, distribution, and transmission power grid constrains the availability of renewable energy for P2H can be difficult to predict. The evaluation of any potential P2H investment while taking into account this consideration, should also examine the effects of incorporating the produced green hydrogen in the gas network. Parameters, including pipeline pressure drop, flowrate, velocity, and, most importantly, composition and calorific content, are crucial for gas network management. A simplified representation of the Irish gas transmission network is created and used as a case study to investigate the impact on gas network operation, of hydrogen generated from curtailed wind power. The variability in wind speed and gas network demands that occur over a 24 h period and with network location are all incorporated into a case study to determine how the inclusion of green hydrogen will affect gas network parameters. This work demonstrates that when using only curtailed renewable electricity during a period with excess renewable power generation, despite using multiple injection points, significant variation in gas quality can occur in the gas network. Hydrogen concentrations of up to 15.8% occur, which exceed the recommended permitted limits for the blending of hydrogen in a natural gas network. These results highlight the importance of modelling both the gas and electricity systems when investigating any potential P2H installation. It is concluded that, for gas networks that decarbonise through the inclusion of blended hydrogen, active management of gas quality is required for all but the smallest of installations.

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Zhou, Suyang, Yuxuan Zhuang, Wei Gu und Zhi Wu. „Operation and Economic Assessment of Hybrid Refueling Station Considering Traffic Flow Information“. Energies 11, Nr. 8 (31.07.2018): 1991. http://dx.doi.org/10.3390/en11081991.

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It is anticipated that the penetration of “Green-Energy” vehicles, including Electric Vehicle (EV), Fuel Cell Vehicle (FCV), and Natural Gas Vehicle (NGV) will keep increasing in next decades. The demand of refueling stations will correspondingly increase for refueling these “Green-Energy” vehicles. While such kinds of “Green-Energy” vehicles can provide both social and economic benefits, effective management of refueling various kinds of these vehicles is necessary to maintain vehicle users’ comfortabilities and refueling station’s return on investment. To tackle these problems, this paper proposes a novel energy management approach for hybrid refueling stations with EV chargers, Hydrogen pumps and gas pumps. Firstly, the detailed models of EV chargers, Hydrogen pumps with electrolyte and hydrogen tank, the gas pumps with gas tank, renewable resources, and battery energy storage systems are established. The forecasting methodologies for renewable energy, electricity price and the traffic flow are also presented to support the hybrid refueling station modeling and operation. Then, a management approach is adopted to manage the refueling various kinds of vehicles with considerations of the refueling station profitability. Finally, the proposed management approach is verified under four different kinds of tariffs- Economy-7, Economy-10, Flat-rate, and Real-Time Pricing (RTP), finding that the proposed management approach has the best performance under RTP tariff. The economic assessment of the Energy Storage System (ESS) is also performed. It is found that the ESS can make the saving up to $127 per day. Different sizes of gas storage tank are compared in the final section as well. The result shows that increasing the size of the tank does not bring attractive extra benefits with the consideration of the investment on enlarging the tank size.

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Al-Zahrani, Salma, Violeta Jevtovic, Khalaf Alenezi, Hani El Moll, Ashanul Haque und Dragoslav Vidovic. „Electrocatalytic hydrogen evolution upon reduction of pyridoxal semicarbazone and thiosemicarbazone-based Cu(II) complexes“. Journal of the Serbian Chemical Society, Nr. 00 (2021): 50. http://dx.doi.org/10.2298/jsc210520050a.

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The growing global demand for renewable energy sources has pushed renewable, green energy sources to the forefront, among which the production of hydrogen gas from water occupies a significant place. To realize this goal, researchers across the globe are developing various systems that could swiftly catalyse the hydrogen evolution reaction (HER) in the highest possible yield. In the present work, we report electrocatalytic HER performances of pyridoxal semicarbazone- and thiosemicarbazone-based Cu(II) complexes, i.e. ([Cu(PLSC)Cl2] and [Cu(PLTSC-H)H2O]Br?H2O). We unambiguously demonstrated that the complexes exhibit enviable level of HER catalytic activity. The catalytic activity of the complexes was not only the function of central metal but it was also controlled by the nature of the coordinating ligand.

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Hinkley, James T. „A New Zealand Perspective on Hydrogen as an Export Commodity: Timing of Market Development and an Energy Assessment of Hydrogen Carriers“. Energies 14, Nr. 16 (10.08.2021): 4876. http://dx.doi.org/10.3390/en14164876.

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Hydrogen is currently receiving significant attention and investment as a key enabler of defossilised global energy systems. Many believe this will eventually result in the international trade of hydrogen as a commodity from countries with significant renewable energy resources, for example New Zealand and Australia, to net energy importing countries including Japan and Korea. Japan has, since 2014, been actively exploring the components of the necessary supply chains, including the assessment of different hydrogen carriers. Public/private partnerships have invested in demonstration projects to assess the comparative merits of liquid hydrogen, ammonia, and organic carriers. On the supply side, significant projects have been proposed in Australia while the impending closure of New Zealand’s Tiwai Point aluminium smelter at the end of 2024 may provide an opportunity for green hydrogen production. However, it is also evident that the transition to a hydrogen economy will take some years and confidence around the timing of supply and demand capacity is essential for new energy infrastructure investment. This paper reviews the expected development of an export market to Japan and concludes that large scale imports are unlikely before the late 2020s. Comparative evaluation of the energy efficiency of various hydrogen carriers concludes that it is too early to call a winner, but that ammonia has key advantages as a fungible commodity today, while liquid hydrogen has the potential to be a more efficient energy carrier. Ultimately it will be the delivered cost of hydrogen that will determine which carriers are used, and while energy efficiency is a key metric, there are other considerations such as infrastructure availability, and capital and operating costs.

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Rabiee, Abbas, Andrew Keane und Alireza Soroudi. „Green hydrogen: A new flexibility source for security constrained scheduling of power systems with renewable energies“. International Journal of Hydrogen Energy 46, Nr. 37 (Mai 2021): 19270–84. http://dx.doi.org/10.1016/j.ijhydene.2021.03.080.

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Ceran, Bartosz. „Multi-Criteria Comparative Analysis of Clean Hydrogen Production Scenarios“. Energies 13, Nr. 16 (12.08.2020): 4180. http://dx.doi.org/10.3390/en13164180.

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Different hydrogen production scenarios need to be compared in regard to multiple, and often distinct aspects. It is well known that hydrogen production technologies based on environmentally-friendly renewable energy sources have higher values of the economic indicators than methods based on fossil fuels. Therefore, how should this decision criterion (environmental) prevail over the other types of decision criteria (technical and economic) to make a scenario where hydrogen production only uses renewable energy sources the most attractive option for a decision-maker? This article presents the results of a multi-variant comparative analysis of scenarios to annually produce one million tons of pure hydrogen (99.999%) via electrolysis in Poland. The compared variants were found to differ in terms of electricity sources feeding the electrolyzers. The research demonstrated that the scenario where hydrogen production uses energy from photovoltaics only becomes the best option for the environmental criterion weighting value at 61%. Taking the aging effect of photovoltaic installation (PV) panels and electrolyzers after 10 years of operation into account, the limit value of the environmental criterion rises to 63%. The carried out analyses may serve as the basis for the creation of systems supporting the development of clean and green hydrogen production technologies.

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Renau, Jordi, Víctor García, Luis Domenech, Pedro Verdejo, Antonio Real, Alberto Giménez, Fernando Sánchez, Antonio Lozano und Félix Barreras. „Novel Use of Green Hydrogen Fuel Cell-Based Combined Heat and Power Systems to Reduce Primary Energy Intake and Greenhouse Emissions in the Building Sector“. Sustainability 13, Nr. 4 (07.02.2021): 1776. http://dx.doi.org/10.3390/su13041776.

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Achieving European climate neutrality by 2050 requires further efforts not only from the industry and society, but also from policymakers. The use of high-efficiency cogeneration facilities will help to reduce both primary energy consumption and CO2 emissions because of the increase in overall efficiency. Fuel cell-based cogeneration technologies are relevant solutions to these points for small- and microscale units. In this research, an innovative and new fuel cell-based cogeneration plant is studied, and its performance is compared with other cogeneration technologies to evaluate the potential reduction degree in energy consumption and CO2 emissions. Four energy consumption profile datasets have been generated from real consumption data of different dwellings located in the Mediterranean coast of Spain to perform numerical simulations in different energy scenarios according to the fuel used in the cogeneration. Results show that the fuel cell-based cogeneration systems reduce primary energy consumption and CO2 emissions in buildings, to a degree that depends on the heat-to-power ratio of the consumer. Primary energy consumption varies from 40% to 90% of the original primary energy consumption, when hydrogen is produced from natural gas reforming process, and from 5% to 40% of the original primary energy consumption if the cogeneration is fueled with hydrogen obtained from renewable energy sources. Similar reduction degrees are achieved in CO2 emissions.

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Filimonova, A. A., A. A. Chichirov, N. D. Chichirova und R. I. Razakova. „Electrochemical technologies for hydrogen powered vehicles“. Power engineering: research, equipment, technology 23, Nr. 2 (21.05.2021): 104–15. http://dx.doi.org/10.30724/1998-9903-2021-23-2-104-115.

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PURPOSE. Consider the electrochemical technologies used for the production of hydrogen at gas stations and the operation of hybrid electric vehicle engines on storage batteries with fuel cells. Comparative analysis of the production and use of energy by electrochemical and traditional methods in vehicles. METHODS. Based on the analysis of literature data and mathematical calculations. RESULTS. For a light electric vehicle, the calculation of the amount of electricity that can be obtained in a fuel cell by processing 1 kg of hydrogen was carried out. It has been shown that a hydrogen electric car can travel about 100 km for 1 kg of hydrogen. A comparison was made of the fuel costs for different types of automotive engines for the current market conditions in Russia and the EU countries. CONCLUSION. Hydrogen can become the environmentally friendly fuel of the future, reduce global dependence on fossil fuel resources and reduce carbon dioxide emissions from the transportation industry. Today, green technologies have made significant progress, modern vehicles of various classes on hydrogen fuel have been developed and sold around the world, and their price characteristics are already comparable to existing traditional technologies. The advantages of electrochemical technologies for the production and use of hydrogen in the road transport sector are sufficient to make hydrogen a serious energy candidate for modern transportation systems.

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Jenal, Norhisyam, Wahyu Kuntjoro, Thomas Arthur Ward, Khairul Imran Sainan und Firdaus Mohamad. „Performance Analysis of Ground-Based Static Test for Hydrogen Fuelcell Propulsion System“. Applied Mechanics and Materials 393 (September 2013): 510–15. http://dx.doi.org/10.4028/www.scientific.net/amm.393.510.

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Combustion engines are increasingly being regarded as unsustainable in the long-term, because of their negative impact on the environment (e.g. pollution, green-house gas production, and global warming). This has generated worldwide interest in propulsion systems based on renewable alternative energy sources for the future. Fuel cell technology is a promising alternative power source because of their high specific energy, efficiency, and reliability. Hydrogen proton exchange membrane fuel cell (PEMFC) in particular produces zero carbon emissions by having only water vapor as the exhaust. Although there has been much research by automotive industries in developing fuel cell hybrid electric vehicles (FCHEV), fuel cell research for aircraft application is relatively new. Therefore, there is a pressing need for research related to development of aircraft fuel cell electric propulsion systems. Universiti Teknologi MARA (UiTM) is conducting static experiments on different configurations of fuel cell electric propulsion systems. The objective of this study is to understand the behavior of a PEMFC propulsion system under a ground-based static test. A 1 kW PEMFC was used as the main power source for a brushless DC motor electric propulsion system. The electrical characteristics, rotational speed, and thrust data were presented for two different electrical propellers. Analyses of the results were used to characterize the effectiveness of the fuel cell system and its balance of plant. The results were beneficial as a predictive method on defining the optimum electric propulsion system performance needed for future actual flight development.

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Kanwal, F., A. Batool, R. Akbar, S. Asim und M. Saleem. „Green and facile synthesis of cerium doped Ni3Fe electrocatalyst for efficient oxygen evolution reaction“. Bulletin of the Chemical Society of Ethiopia 34, Nr. 2 (28.10.2020): 353–63. http://dx.doi.org/10.4314/bcse.v34i2.12.

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Electrochemical water splitting is the most promising pathway to produce high-purity hydrogen to alleviate global energy crisis. This reaction demands inexpensive, efficient and robust electrocatalyst for its commercial use. Herein, we demonstrate an effective, facile and scalable method for the synthesis of cerium doped Ni3Fe nanostructures as an electrocatalyst for oxygen evolution reaction (OER) by following simple chemical bath deposition route. The different molar ratios (3, 6 and 12 mM) of cerium in the chemical bath were used to study its effect on the structural and the electrochemical properties of the Ni3Fe nanostructured films. Doping of cerium contents induced variations in the morphology of deposited Ni3Fe nanostructures. The optimized electrocatalyst Ni3Fe/Ce-6 yielded high surface area catalyst nanosheets uniformly deposited on three-dimensional conductive scaffold to ensure increase in the exposure of doped Ni3Fe catalytic sites with high electrical conductivity. As a result, this earth-abundant electrocatalyst affords high OER performance with a small overpotential of 310 mV versus reversible hydrogen electrode (RHE) at 10 mA cm-2 and retains good stability up to ~ 10 h in alkaline electrolyte. This scalable strategy has great potential in future advancement of efficient and low-cost electrocatalysts for their large-scale application in energy conversion systems. KEY WORDS: Oxygen evolution, Electrocatalyst, Ni3Fe nanostructures, Cerium, Alkaline electrolyte Bull. Chem. Soc. Ethiop. 2020, 34(2), 353-363 DOI: https://dx.doi.org/10.4314/bcse.v34i2.12

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Kotze, Rick, Alan C. Brent, Josephine Musango, Imke de Kock und Leonard A. Malczynski. „Investigating the Investments Required to Transition New Zealand’s Heavy-Duty Vehicles to Hydrogen“. Energies 14, Nr. 6 (16.03.2021): 1646. http://dx.doi.org/10.3390/en14061646.

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Reducing greenhouse gas emissions in the transport sector is known to be an important contribution to climate change mitigation. Some parts of the transport sector are particularly difficult to decarbonize; this includes the heavy-duty vehicle sector, which is considered one of the “hard-to-abate” sectors of the economy. Transitioning from diesel trucks to hydrogen fuel cell trucks has been identified as a potential way to decarbonize the sector. However, the current and future costs and efficiencies of the enabling technologies remain unclear. In light of these uncertainties, this paper investigates the investments required to decarbonize New Zealand’s heavy-duty vehicle sector with green hydrogen. By combining system dynamics modelling literature and hydrogen transition modelling literature a customized methodology is developed for modelling hydrogen transitions with system dynamics modelling. Results are presented in terms of the investments required to purchase the hydrogen production capacity and the investments required to supply electricity to the hydrogen production systems. Production capacity investments are found to range between 1.59 and 2.58 billion New Zealand Dollars, and marginal electricity investments are found to range between 4.14 and 7.65 billion New Zealand Dollars. These investments represent scenarios in which 71% to 90% of the heavy-duty vehicle fleet are replaced with fuel cell trucks by 2050. The wide range of these findings reflects the large uncertainties in estimates of how hydrogen technologies will develop over the course of the next thirty years. Policy recommendations are drawn from these results, and a clear opportunity for future work is outlined. Most notably, the results from this study should be compared with research investigating the investments required to decarbonize the heavy-duty vehicle sectors with alternative technologies such as battery-electric trucks, biodiesel, and catenary systems. Such a comparison would ensure that the most cost effective decarbonization strategy is employed.

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Molinari, Raffaele, Cristina Lavorato, Pietro Argurio, Kacper Szymański, Dominika Darowna und Sylwia Mozia. „Overview of Photocatalytic Membrane Reactors in Organic Synthesis, Energy Storage and Environmental Applications“. Catalysts 9, Nr. 3 (04.03.2019): 239. http://dx.doi.org/10.3390/catal9030239.

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This paper presents an overview of recent reports on photocatalytic membrane reactors (PMRs) in organic synthesis as well as water and wastewater treatment. A brief introduction to slurry PMRs and the systems equipped with photocatalytic membranes (PMs) is given. The methods of PM production are also presented. Moreover, the process parameters affecting the performance of PMRs are characterized. The applications of PMRs in organic synthesis are discussed, including photocatalytic conversion of CO2, synthesis of KA oil by photocatalytic oxidation, conversion of acetophenone to phenylethanol, synthesis of vanillin and phenol, as well as hydrogen production. Furthermore, the configurations and applications of PMRs for removal of organic contaminants from model solutions, natural water and municipal or industrial wastewater are described. It was concluded that PMRs represent a promising green technology; however, before the application in industry, additional studies are still required. These should be aimed at improvement of process efficiency, mainly by development and application of visible light active photocatalysts and novel membranes resistant to the harsh conditions prevailing in these systems.

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Williams, Mark C., Bruce R. Utz und Kevin M. Moore. „DOE FE Distributed Generation Program“. Journal of Fuel Cell Science and Technology 1, Nr. 1 (28.04.2004): 18–20. http://dx.doi.org/10.1115/1.1782920.

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The U.S. Department of Energy’s (DOE) Office of Fossil Energy’s (FE) National Energy Technology Laboratory (NETL), in partnership with private industries, is leading the development and demonstration of high efficiency solid oxide fuel cells (SOFCs) and fuel cell turbine hybrid power generation systems for near term distributed generation (DG) markets with an emphasis on premium power and high reliability. NETL is partnering with Pacific Northwest National Laboratory (PNNL) in developing new directions in research under the Solid-State Energy Conversion Alliance (SECA) initiative for the development and commercialization of modular, low cost, and fuel flexible SOFC systems. The SECA initiative, through advanced materials, processing and system integration research and development, will bring the fuel cell cost to $400 per kilowatt (kW) for stationary and auxiliary power unit (APU) markets. The President of the U.S. has launched us into a new hydrogen economy. The logic of a hydrogen economy is compelling. The movement to a hydrogen economy will accomplish several strategic goals. The U.S. can use its own domestic resources—solar, wind, hydro, and coal. The U.S. uses 20 percent of the world’s oil but has only 3 percent of resources. Also, the U.S. can reduce green house gas emissions. Clear Skies and Climate Change initiatives aim to reduce carbon dioxide (CO2), nitrogen oxides (NOx), and sulfur dioxide (SO2) emissions. SOFCs have no emissions, so they figure significantly in these DOE strategies. In addition, DG—SOFCs, reforming, energy storage—has significant benefit for enhanced security and reliability. The use of fuel cells in cars is expected to bring about the hydrogen economy. However, commercialization of fuel cells is expected to proceed first through portable and stationary applications. This logic says to develop SOFCs for a wide range of stationary and APU applications, initially for conventional fuels, then switch to hydrogen. Like all fuel cells, the SOFC will operate even better on hydrogen than conventional fuels. The SOFC hybrid is a key part of the FutureGen plants. FutureGen is a major new Presidential initiative to produce hydrogen from coal. The highly efficient SOFC hybrid plant will produce electric power and other parts of the plant could produce hydrogen and sequester CO2. The hydrogen produced can be used in fuel cell cars and for SOFC DG applications.

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Rosenstiel, Andreas, Nathalie Monnerie, Jürgen Dersch, Martin Roeb, Robert Pitz-Paal und Christian Sattler. „Electrochemical Hydrogen Production Powered by PV/CSP Hybrid Power Plants: A Modelling Approach for Cost Optimal System Design“. Energies 14, Nr. 12 (10.06.2021): 3437. http://dx.doi.org/10.3390/en14123437.

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Global trade of green hydrogen will probably become a vital factor in reaching climate neutrality. The sunbelt of the Earth has a great potential for large-scale hydrogen production. One promising pathway to solar hydrogen is to use economically priced electricity from photovoltaics (PV) for electrochemical water splitting. However, storing electricity with batteries is still expensive and without storage only a small operating capacity of electrolyser systems can be reached. Combining PV with concentrated solar power (CSP) and thermal energy storage (TES) seems a good pathway to reach more electrolyser full load hours and thereby lower levelized costs of hydrogen (LCOH). This work introduces an energy system model for finding cost-optimal designs of such PV/CSP hybrid hydrogen production plants based on a global optimization algorithm. The model includes an operational strategy which improves the interplay between PV and CSP part, allowing also to store PV surplus electricity as heat. An exemplary study for stand-alone hydrogen production with an alkaline electrolyser (AEL) system is carried out. Three different locations with different solar resources are considered, regarding the total installed costs (TIC) to obtain realistic LCOH values. The study shows that a combination of PV and CSP is an auspicious concept for large-scale solar hydrogen production, leading to lower costs than using one of the technologies on its own. For today’s PV and CSP costs, minimum levelized costs of hydrogen of 4.04 USD/kg were determined for a plant located in Ouarzazate (Morocco). Considering the foreseen decrease in PV and CSP costs until 2030, cuts the LCOH to 3.09 USD/kg while still a combination of PV and CSP is the most economic system.

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Gracia, Lorién, Pedro Casero, Cyril Bourasseau und Alexandre Chabert. „Use of Hydrogen in Off-Grid Locations, a Techno-Economic Assessment“. Energies 11, Nr. 11 (13.11.2018): 3141. http://dx.doi.org/10.3390/en11113141.

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Diesel generators are currently used as an off-grid solution for backup power, but this causes CO2 and GHG emissions, noise emissions, and the negative effects of the volatile diesel market influencing operating costs. Green hydrogen production, by means of water electrolysis, has been proposed as a feasible solution to fill the gaps between demand and production, the main handicaps of using exclusively renewable energy in isolated applications. This manuscript presents a business case of an off-grid hydrogen production by electrolysis applied to the electrification of isolated sites. This study is part of the European Ely4off project (n° 700359). Under certain techno-economic hypothesis, four different system configurations supplied exclusively by photovoltaic are compared to find the optimal Levelized Cost of Electricity (LCoE): photovoltaic-batteries, photovoltaic-hydrogen-batteries, photovoltaic-diesel generator, and diesel generator; the influence of the location and the impact of different consumptions profiles is explored. Several simulations developed through specific modeling software are carried out and discussed. The main finding is that diesel-based systems still allow lower costs than any other solution, although hydrogen-based solutions can compete with other technologies under certain conditions.

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Liu, En-Jui, Yi-Hsuan Hung und Che-Wun Hong. „Improved Metaheuristic Optimization Algorithm Applied to Hydrogen Fuel Cell and Photovoltaic Cell Parameter Extraction“. Energies 14, Nr. 3 (26.01.2021): 619. http://dx.doi.org/10.3390/en14030619.

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As carriers of green energy, proton exchange membrane fuel cells (PEMFCs) and photovoltaic (PV) cells are complex and nonlinear multivariate systems. For simulation analysis, optimization control, efficacy prediction, and fault diagnosis, it is crucial to rapidly and accurately establish reliability modules and extract parameters from the system modules. This study employed three types of particle swarm optimization (PSO) algorithms to find the optimal parameters of two energy models by minimizing the sum squared errors (SSE) and roots mean squared errors (RMSE). The three algorithms are inertia weight PSO, constriction PSO, and momentum PSO. The obtained calculation results of these three algorithms were compared with those obtained using algorithms from other relevant studies. This study revealed that the use of momentum PSO enables rapid convergence (under 30 convergence times) and the most accurate modeling and yields the most stable parameter extraction (SSE of PEMFC is 2.0656, RMSE of PV cells is 8.839 · 10−4). In summary, momentum PSO is the algorithm that is most suitable for system parameter identification with multiple dimensions and complex modules.

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Bondarenko, Svіtlana, Iryna Perevozova und Tetiana Maksimenko. „Implementation of innovative projects using renewable energy sources in the fields of “future economy”“. Journal of Scientific Papers "Social development and Security" 10, Nr. 3 (30.06.2020): 145–57. http://dx.doi.org/10.33445/sds.2020.10.3.13.

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The aim of the article is to study the implementation of innovative projects for the use of renewable energy sources in the “economy of the future”. According to the concept of “green" energy transition, the following areas of "economy of the future" are identified: energy efficient industry, buildings, heat energy; electric transport; circulating economy, waste reduction; support for research and innovation on electricity storage, production and storage of green hydrogen; digitalization and technological changes; renewable energy sources – wind, solar, bioenergy. It is proved that renewable energy sources can meet 80% growth in electricity demand over the next 10 years. By 2025, renewable energy sources will displace coal as the main means of electricity generation. If states adopt more aggressive policies, the role of renewable energy will be even more active in the next five years. It is proved that it is important to create an appropriate market environment to attract large-scale private investment in innovative renewable energy projects. After all, without sufficient investment, networks will be a weak link in the transformation of the electricity sector, which will affect the reliability and security of electricity supply. The transition to renewable energy sources in the general energy supply, including transport and heating, is most active in large cities. To transition the city to the “green” energy, the issues of attracting investment, changing consumer behavior, integration of electricity with heat supply and transport, the state of existing energy infrastructure (electricity, gas, heating networks), distribution of energy consumption between sectors (buildings, mobility) and players in supply (large energy companies, enterprises, cooperatives). The research of the basic tendencies of realization of projects of use of renewable energy sources in Ukraine is carried out. To ensure competitive conditions for the production of electricity from alternative energy sources, the introduction of incentive mechanisms and the installation of capacities for the accumulation of electricity at power plants is envisaged. Financial support for renewable energy at the state level is provided in two areas: tax benefits and credit support. Among the tax benefits and mechanisms in world practice are the following: investment tax credit; production tax credit; mechanism of partial or full compensation of interest for the use of loans by industrial companies and individual farms for the installation of energy storage systems; mechanism for exemption from taxation of imported equipment for energy storage systems, etc. However, Ukraine has not yet taken sufficient legislative and diplomatic steps to do so. Important are the problems of balancing the network, defaults and debts to market participants, the restructuring of the “green” tariff.

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Monarca, D., A. Colantoni, M. Cecchini, L. Longo, L. Vecchione, M. Carlini und A. Manzo. „Energy Characterization and Gasification of Biomass Derived by Hazelnut Cultivation: Analysis of Produced Syngas by Gas Chromatography“. Mathematical Problems in Engineering 2012 (2012): 1–9. http://dx.doi.org/10.1155/2012/102914.

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Modern agriculture is an extremely energy intensive process. However, high agricultural productivities and the growth of green revolution has been possible only by large amount of energy inputs, especially those coming from fossil fuels. These energy resources have not been able to provide an economically viable solution for agricultural applications. Biomass energy-based systems had been extensively used for transportation and on farm systems during World War II: the most common and reliable solution was wood or biomass gasification. The latter means incomplete combustion of biomass resulting in production of combustible gases which mostly consist of carbon monoxide (CO), hydrogen (H2) and traces of methane (CH4). This mixture is called syngas, which can be successfully used to run internal combustion engines (both compression and spark ignition) or as substitute for furnace oil in direct heat applications. The aim of the present paper is to help the experimentation of innovative plants for electric power production using agro-forest biomass derived by hazelnut cultivations. An additional purpose is to point out a connection among the chemical and physical properties of the outgoing syngas by biomass characterization and gas-chromatography analysis.

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Bianco, Giovanni, Barbara Bonvini, Stefano Bracco, Federico Delfino, Paola Laiolo und Giorgio Piazza. „Key Performance Indicators for an Energy Community Based on Sustainable Technologies“. Sustainability 13, Nr. 16 (06.08.2021): 8789. http://dx.doi.org/10.3390/su13168789.

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As reported in the “Clean energy for all Europeans package” set by the EU, a sustainable transition from fossil fuels towards cleaner energy is necessary to improve the quality of life of citizens and the livability in cities. The exploitation of renewable sources, the improvement of energy performance in buildings and the need for cutting-edge national energy and climate plans represent important and urgent topics to be faced in order to implement the sustainability concept in urban areas. In addition, the spread of polygeneration microgrids and the recent development of energy communities enable a massive installation of renewable power plants, high-performance small-size cogeneration units, and electrical storage systems; moreover, properly designed local energy production systems make it possible to optimize the exploitation of green energy sources and reduce both energy supply costs and emissions. In the present paper, a set of key performance indicators is introduced in order to evaluate and compare different energy communities both from a technical and environmental point of view. The proposed methodology was used in order to assess and compare two sites characterized by the presence of sustainable energy infrastructures: the Savona Campus of the University of Genoa in Italy, where a polygeneration microgrid has been in operation since 2014 and new technologies will be installed in the near future, and the SPEED2030 District, an urban area near the Campus where renewable energy power plants (solar and wind), cogeneration units fed by hydrogen and storage systems are planned to be installed.

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Reisz, Aloysius I. „Earthrise“. Mechanical Engineering 124, Nr. 05 (01.05.2002): 42–46. http://dx.doi.org/10.1115/1.2002-may-1.

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This article focuses on the Apollo program that was a remarkable feat of engineering and a heroic human endeavor. It proved that mankind is not bound to Earth. The Apollo missions endowed us with a new sense of confidence in our intelligence and an awareness of our existence. Above all, the view of the graceful Earth from the moon inspired us to engineer better systems for our home planet. Apollo’s engineering leaders showed how to envision solutions to achieve objectives in a required time. Green engineering is developing clean energy and life systems that conserve Earth’s ecology. Clean energy can be obtained from the first elements of the universe, light and hydrogen. Energy from nuclear fusion leaves no hydrocarbon pollutants. Clean energy is also obtained from wind, celestial heat, biomass, and hydrocarbon matter before heavier Earth elements are entrained. Engineering is the application of human intelligence for the betterment of life. Engineers must not be satisfied with a role of merely making rote calculations. Rather, vision and leadership in developing and implementing new technologies should be provided that will allow perpetual use of the Earth and its resources.

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Alirahmi, Seyed Mojtaba, Amir Reza Razmi und Ahmad Arabkoohsar. „Comprehensive assessment and multi-objective optimization of a green concept based on a combination of hydrogen and compressed air energy storage (CAES) systems“. Renewable and Sustainable Energy Reviews 142 (Mai 2021): 110850. http://dx.doi.org/10.1016/j.rser.2021.110850.

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Jäger-Waldau, Arnulf. „Snapshot of photovoltaics − March 2021“. EPJ Photovoltaics 12 (2021): 2. http://dx.doi.org/10.1051/epjpv/2021002.

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For the past 10 years, photovoltaic electricity generation has been the fastest-growing power generation source worldwide. It took almost six decades to achieve 100 GW of solar energy capacity in 2012, but the 1 TW barrier is likely to be broken during 2022. Despite the ongoing COVID-19 pandemic, the overall investments in solar energy have increased by 12% to USD 148.6 billion (EUR 125 billion). In 2020, more than 135 GW of new solar photovoltaic electricity generation capacity was installed. The recovery of China, the continuous growths in Europe and the USA as well as new emerging markets were the main drivers. The number of countries installing more than 1 GW annually has increased to 18 in 2020. The continuation of price reductions in the battery storage sector has again resulted in a growing market for local battery storage systems in solar farms as well as decentralised photovoltaic electricity generation systems. Apart from classic electricity use, renewable electricity for the generation of green hydrogen will become more and more important in the future.

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Xu, Yufei, Jingxuan Long, Jian He und Hu Li. „Alcohol-mediated Reduction of Biomass-derived Furanic Aldehydes via Catalytic Hydrogen Transfer“. Current Organic Chemistry 23, Nr. 20 (24.12.2019): 2168–79. http://dx.doi.org/10.2174/1385272823666190723141955.

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With the depletion of fossil energy, liquid biofuels are becoming one of the effective alternatives to replace fossil fuels. The catalytic transfer and hydrogenation of biomass-based furanic compounds into fuels and value-added chemicals has become a spotlight in this field. Gas hydrogen is often used as the H-donor for the hydrogenation reactions. It is a very straightforward and simple method to implement, but sometimes it comes with the danger of operation and the difficulty of regulation. In recent years, diverse liquid hydrogen donor reagents have been employed in the catalytic transfer hydrogenation (CTH) of biomass. Amongst those H-donors, alcohol is a kind of green and benign reagent that has been used in different biomass conversion reactions. This type of reagent is very convenient to use, and the involved operation process is safe, as compared to that of H2. In this review, the application of alcohols as liquid H-donors in the catalytic transfer hydrogenation of biomass-derived furanic compounds is depicted, and the representative reaction mechanisms are discussed. Emphasis is also laid on the selective control of product distribution in the described catalytic systems.

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Obenaus-Emler, Robert, Markus Lehner, Mariaelena Murphy und Corina Pacher. „Educational Concept for Citizens’ Awareness Towards Technological Advancements for a Sustainable Society—Introducing a Concept for Interactive Societal Learning on Hydrogen and Carbon“. BHM Berg- und Hüttenmännische Monatshefte 166, Nr. 6 (Juni 2021): 314–22. http://dx.doi.org/10.1007/s00501-021-01121-2.

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AbstractHydrogen is a key element of our everyday life. It is an irreplaceable feedstock for the production of fertilisers, fuels, and chemicals. From a scientific point of view, hydrogen can additionally play a major role in future energy systems and help to decarbonise the sectors industry, heat and power generation as well as transport and mobility. Thus, it can contribute to the energy transition and the reduction of greenhouse gas emissions at a large scale and consequently help to mitigate climate change. It is, therefore, a key building block to reach the remarkably challenging goals recently stated in the European Green Deal. Therefore, the overarching question is whether hydrogen can measure up to the great expectations raised and how creating public awareness and education can contribute in achieving a social license to operate for emerging new technological developments in this context. Education is not solely an instrument for academic excellence but also a powerful tool to raise public awareness with regard to the development of new technologies. While the main goal of the pyrolysis project is to research sustainable means of hydrogen production, the project also considers its role within the community as a positive side effect. To safeguard and promote the scientific social licence to operate, an educational programme will be additionally developed to raise civic awareness and grant access to the developments made in the project in a learning lab, which will have open access for schools and the general public.

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Tan, Raymond R., und Alvin B. Culaba. „Sensitivity Analysis of the Life-Cycle Inventories of Electricity and Hydrogen as Energy Vectors for the Philippine Automative Transport Sector“. ASEAN Journal of Chemical Engineering 2, Nr. 1 (20.10.2008): 21. http://dx.doi.org/10.22146/ajche.50799.

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The Philippine automotive transport sector accounts for a significant portion ofthe country's petroleum consumption and air emissions. Research in alternative fuels for road vehicles is thus an essential element in the country's long-term-electrical environmental management strategy. Two radical vehicle technologies propulsion systems and fuel hydrogen for fuel cells - are widely considered to be the most promising energy vectors from an environmental standpoint. Electric vehicles (EV) and fuel cell vehicles (FCV) are driven by electric motors; the former use electricity stored in batteries, while the latter generate electricity from the oxidation of hydrogen. Potentially, both electric power and fuel hydrogen can be sustainably produced using renewable energy sources, and their use in vehicles generates almost no direct pollution. However, life-cycle assessment (LCA) may reveal significant environmental impacts from the infrastructure required to produce and distribute these energy vectors on a commercial scale. This study quantifies the life-cycle air emissions and energy balances associated with the use of electricity and hydrogen for motor vehicle propulsion in order to determine which fuel offers more environmental benefits. The assessment uses a modified version of the GREET 1.Sa fuel cycle inventory model, with corrections made to account for Philippine conditions. Sensitivity analysis is performed in the model to determine the effect of marginal power generation mix and system transmission losses on the life-cycle inventories of both energy vectors. The results of the simulation indicate that for a given marginal power generation mix, there is no clear-cut advantage in terms of environmental performance for either hydrogen or electricity.

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Sood, Sumit, Om Prakash, Mahdi Boukerdja, Jean-Yves Dieulot, Belkacem Ould-Bouamama, Mathieu Bressel und Anne-Lise Gehin. „Generic Dynamical Model of PEM Electrolyser under Intermittent Sources“. Energies 13, Nr. 24 (11.12.2020): 6556. http://dx.doi.org/10.3390/en13246556.

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Proton Exchange Membrane (PEM) water electrolysis system is one of the promising technologies to produce green hydrogen from renewable energy sources (wind and solar). However, performance and dynamic analysis of PEM water electrolysis systems are challenging due to the intermittent nature of such sources and involved multi-physical behaviour of the components and subsystems. This study proposes a generic dynamical model of the PEM electrolysis system represented in a modular fashion using Bond Graph (BG) as a unified modelling approach. Causal and functional properties of the BG facilitate the formal PEM electrolyser model to adapt and to fit the different configurations of the electrolyser ranging from laboratory scale to industrial scale. The system-specific key parameter values are identified optimally for a laboratory-scale electrolyser system running on a multi-source energy platform using experimental data. The mean absolute percentage error between simulation and experimental data is found to be less than 5%. The performance characteristic curves of the electrolyser are predicted at different operating temperatures using the identified key parameters. The predicted performance is in good agreement with the expected behaviour of the electrolyser found in the literature. The model also estimates the different energy losses and the real-time efficiency of the system under dynamic inputs. With these capabilities, the developed model provides an economical mean for design, control, and diagnosis development of such systems.

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Pivovarova, Nadezhda A., Ekaterina S. Akishina, Nadezhda T. Berberova und Elena V. Shinkar. „PROMISING TECHNOLOGY FOR REMOVAL AND DISPOSAL OF HYDROGEN SULFIDE FROM FUEL OIL“. IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 63, Nr. 8 (23.06.2020): 39–53. http://dx.doi.org/10.6060/ivkkt.20206308.6143.

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The presence of hydrogen sulfide in fuel oil is a danger, since hydrogen sulfide is concentrated in the gas phase of tanks, vessels and tanks truck that when carrying out operations of drainage-fulness can lead to an excess of its MAC in air and to the creation of explosive mixtures. The concentration of H2S in fuel oil produced at refineries is 20-500 ppm, while its content in commercial fuel is limited to 10 ppm. Analytical methods of definition of concentration of a hydrogen sulfide in oil products are considered. Industrial and promising technologies for reducing H2S in fuel oil, their main merits and demerits are presented. The possibilities of low-energy wave technologies in the refinement of petroleum and oil products and mechanisms of action of ultrasound and constant magnetic field on oil disperse systems are shown. The hydrogen sulfide extracted from fuel oil neither on volumes, nor on concentration can't be used as independent raw materials for processing into elemental sulfur in the Claus process and is a toxic by-product. At the same time, hydrogen sulfide-containing wastes can serve as valuable raw materials for the production of wide range of useful organic compounds (antioxidants, drugs, pesticides, fungicides) in electrochemical processes. In processes of low-tonnage chemistry, electrochemical processes are relevant. As a result of anode or cathode activation of a hydrogen sulfide (alkanethiols) at ambient temperature and atmospheric pressure the thiyl (alkylthiyl) radical is formed. Along with products of a thiolation of organic compounds are formed also mono - di - and the trisulphides having higher biological activity and lower toxiferous in comparison with thiols. The competitiveness of electrosynthesis is very high, it is considered as processes of waste-free production as at the heart of it ecologically focused idea of "green chemistry" is concluded.

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Yodwong, Burin, Damien Guilbert, Matheepot Phattanasak, Wattana Kaewmanee, Melika Hinaje und Gianpaolo Vitale. „AC-DC Converters for Electrolyzer Applications: State of the Art and Future Challenges“. Electronics 9, Nr. 6 (29.05.2020): 912. http://dx.doi.org/10.3390/electronics9060912.

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The main objective of the article is to provide a thorough review of currently used AC-DC converters for alkaline and proton exchange membrane (PEM) electrolyzers in power grid or wind energy conversion systems. Based on the current literature, this article aims at emphasizing the advantages and drawbacks of AC-DC converters mainly based on thyristor rectifier bridges and chopper-rectifiers. The analysis is mainly focused on the current issues for these converters in terms of specific energy consumption, current ripple, reliability, efficiency, and power quality. From this analysis, it is shown that thyristors-based rectifiers are particularly fit for high-power applications but require the use of active and passive filters to enhance the power quality. By comparison, the association combination of the chopper-rectifier can avoid the use of bulky active and passive filters since it can improve power quality. However, the use of a basic chopper (i.e., buck converter) presents several disadvantages from the reliability, energy efficiency, voltage ratio, and current ripple point of view. For this reason, new emerging DC-DC converters must be employed to meet these important issues according to the availability of new power switching devices. Finally, based on the authors’ experience in power conversion for PEM electrolyzers, a discussion is provided regarding the future challenges that must face power electronics for green hydrogen production based on renewable energy sources.

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Fiorenza, Roberto, Marcello Condorelli, Luisa D’Urso, Giuseppe Compagnini, Marianna Bellardita, Leonardo Palmisano und Salvatore Scirè. „Catalytic and Photothermo-catalytic Applications of TiO2-CoOx Composites“. Journal of Photocatalysis 1, Nr. 1 (02.10.2020): 3–15. http://dx.doi.org/10.2174/2665976x01666200219113505.

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Objective: The necessity to have green and sustainable industrial processes has promoted new technologies for air and water purification together with the research of new energy sources. In this contest, the TiO2-based photocatalysis can be considered a promising route for both environmental applications aIn this work, we have investigated the photocatalytic performance of TiO2-CoOx composites on both photooxidation and photoreduction reactions. Specifically, we have compared the performance of the composites in the thermo-catalytic, photo-catalytic and photothermal-catalytic oxidation of ethanol chosen as model volatile organic compound (VOC) and in the photocatalytic hydrogen production by simulated solar light from aqueous solution of ethanol.nd hydrogen production through water splitting. Background: The necessity to have green and sustainable industrial processes has promoted new technologies for air and water purification together with the research of new energy sources. In this contest, the TiO2-based photocatalysis can be considered a promising route for both environmental applications and hydrogen production through water splitting. Methods: The samples were prepared with a simple impregnation method, and were characterized by Scanning Electron (SEM) and Transmission Electron (TEM) microscopies, X-ray powder diffraction (XRD), N2 adsorption-desorption measurements, Temperature Programmed Reduction in hydrogen (H2- TPR) and X-ray Photoelectron (XPS), Raman, UV-Vis Diffuse Reflectance (UV-Vis DRS) and Photoluminescence (PL) spectroscopies. The catalytic and photocatalytic activity were carried out on pyrex reactors irradiated with a solar lamp and analyzing the reactions products through gas chromatography. Results: The presence and the amount of cobalt oxide were found crucial in determining the performance of the TiO2-based composites for both the catalytic and photocatalytic processes. In particular, the addition of 1 weight percent of CoOx led to the best performance in the photocatalytic processes, whereas a higher amount was beneficial in the thermo-catalytic tests. The multi-catalytic approach based on the synergistic effect of photocatalysis and thermocatalysis in the presence of the TiO2-1%CoOx sample allowed the temperature necessary to obtain 50% ethanol conversion and 50% yield in CO2 to be reduced by 40°C and 50°C, respectively. The same sample was also the best catalyst for photocatalytic solar H2 production. Conclusion: The presence of small amounts of cobalt oxide leads to an efficient composite with TiO2 facilitating the space charge separation and increasing the lifetime of the generated photoholes and electrons. The wide versatility of TiO2-CoOx catalysts both for photooxidation and photoreduction reactions motivates to further exploit the use of these systems in real solar-driven photocatalysis.

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Esmaeilzadeh, Feridun, Nazanin Hamedi, Dornaz Karimipourfard und Ali Rasoolzadeh. „An insight into the role of the association equations of states in gas hydrate modeling: a review“. Petroleum Science 17, Nr. 5 (18.07.2020): 1432–50. http://dx.doi.org/10.1007/s12182-020-00471-9.

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Abstract Encouraged by the wide spectrum of novel applications of gas hydrates, e.g., energy recovery, gas separation, gas storage, gas transportation, water desalination, and hydrogen hydrate as a green energy resource, as well as CO2 capturing, many scientists have focused their attention on investigating this important phenomenon. Of course, from an engineering viewpoint, the mathematical modeling of gas hydrates is of paramount importance, as anticipation of gas hydrate stability conditions is effective in the design and control of industrial processes. Overall, the thermodynamic modeling of gas hydrate can be tackled as an equilibration of three phases, i.e., liquid, gas, and solid hydrate. The inseparable component in all hydrate systems, water, is highly polar and non-ideal, necessitating the use of more advanced equation of states (EoSs) that take into account more intermolecular forces for thermodynamic modeling of these systems. Motivated by the ever-increasing number of publications on this topic, this study aims to review the application of associating EoSs for the thermodynamic modeling of gas hydrates. Three most important hydrate-based models available in the literature including the van der Waals–Platteeuw (vdW–P) model, Chen–Guo model, and Klauda–Sandler model coupled with CPA and SAFT EoSs were investigated and compared with cubic EoSs. It was concluded that the CPA and SAFT EoSs gave very accurate results for hydrate systems as they take into account the association interactions, which are very crucial in gas hydrate systems in which water, methanol, glycols, and other types of associating compounds are available. Moreover, it was concluded that the CPA EoS is easier to use than the SAFT-type EoSs and our suggestion for the gas hydrate systems is the CPA EoS.

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Holappa, Lauri. „A General Vision for Reduction of Energy Consumption and CO2 Emissions from the Steel Industry“. Metals 10, Nr. 9 (19.08.2020): 1117. http://dx.doi.org/10.3390/met10091117.

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The 2018 IPCC (The Intergovernmental Panel on Climate Change’s) report defined the goal to limit global warming to 1.5 °C by 2050. This will require “rapid and far-reaching transitions in land, energy, industry, buildings, transport, and cities”. The challenge falls on all sectors, especially energy production and industry. In this regard, the recent progress and future challenges of greenhouse gas emissions and energy supply are first briefly introduced. Then, the current situation of the steel industry is presented. Steel production is predicted to grow by 25–30% by 2050. The dominant iron-making route, blast furnace (BF), especially, is an energy-intensive process based on fossil fuel consumption; the steel sector is thus responsible for about 7% of all anthropogenic CO2 emissions. In order to take up the 2050 challenge, emissions should see significant cuts. Correspondingly, specific emissions (t CO2/t steel) should be radically decreased. Several large research programs in big steelmaking countries and the EU have been carried out over the last 10–15 years or are ongoing. All plausible measures to decrease CO2 emissions were explored here based on the published literature. The essential results are discussed and concluded. The specific emissions of “world steel” are currently at 1.8 t CO2/t steel. Improved energy efficiency by modernizing plants and adopting best available technologies in all process stages could decrease the emissions by 15–20%. Further reductions towards 1.0 t CO2/t steel level are achievable via novel technologies like top gas recycling in BF, oxygen BF, and maximal replacement of coke by biomass. These processes are, however, waiting for substantive industrialization. Generally, substituting hydrogen for carbon in reductants and fuels like natural gas and coke gas can decrease CO2 emissions remarkably. The same holds for direct reduction processes (DR), which have spread recently, exceeding 100 Mt annual capacity. More radical cut is possible via CO2 capture and storage (CCS). The technology is well-known in the oil industry; and potential applications in other sectors, including the steel industry, are being explored. While this might be a real solution in propitious circumstances, it is hardly universally applicable in the long run. More auspicious is the concept that aims at utilizing captured carbon in the production of chemicals, food, or fuels e.g., methanol (CCU, CCUS). The basic idea is smart, but in the early phase of its application, the high energy-consumption and costs are disincentives. The potential of hydrogen as a fuel and reductant is well-known, but it has a supporting role in iron metallurgy. In the current fight against climate warming, H2 has come into the “limelight” as a reductant, fuel, and energy storage. The hydrogen economy concept contains both production, storage, distribution, and uses. In ironmaking, several research programs have been launched for hydrogen production and reduction of iron oxides. Another global trend is the transfer from fossil fuel to electricity. “Green” electricity generation and hydrogen will be firmly linked together. The electrification of steel production is emphasized upon in this paper as the recycled scrap is estimated to grow from the 30% level to 50% by 2050. Finally, in this review, all means to reduce specific CO2 emissions have been summarized. By thorough modernization of production facilities and energy systems and by adopting new pioneering methods, “world steel” could reach the level of 0.4–0.5 t CO2/t steel and thus reduce two-thirds of current annual emissions.

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Mainardis, Matia, Marco Buttazzoni und Daniele Goi. „Up-Flow Anaerobic Sludge Blanket (UASB) Technology for Energy Recovery: A Review on State-of-the-Art and Recent Technological Advances“. Bioengineering 7, Nr. 2 (10.05.2020): 43. http://dx.doi.org/10.3390/bioengineering7020043.

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Up-flow anaerobic sludge blanket (UASB) reactor belongs to high-rate systems, able to perform anaerobic reaction at reduced hydraulic retention time, if compared to traditional digesters. In this review, the most recent advances in UASB reactor applications are critically summarized and discussed, with outline on the most critical aspects for further possible future developments. Beside traditional anaerobic treatment of soluble and biodegradable substrates, research is actually focusing on the treatment of refractory and slowly degradable matrices, thanks to an improved understanding of microbial community composition and reactor hydrodynamics, together with utilization of powerful modeling tools. Innovative approaches include the use of UASB reactor for nitrogen removal, as well as for hydrogen and volatile fatty acid production. Co-digestion of complementary substrates available in the same territory is being extensively studied to increase biogas yield and provide smooth continuous operations in a circular economy perspective. Particular importance is being given to decentralized treatment, able to provide electricity and heat to local users with possible integration with other renewable energies. Proper pre-treatment application increases biogas yield, while a successive post-treatment is needed to meet required effluent standards, also from a toxicological perspective. An increased full-scale application of UASB technology is desirable to achieve circular economy and sustainability scopes, with efficient biogas exploitation, fulfilling renewable energy targets and green-house gases emission reduction, in particular in tropical countries, where limited reactor heating is required.

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Pokharel, Sunita, Mohsen Ayoobi und V’yacheslav Akkerman. „Computational Analysis of Premixed Syngas/Air Combustion in Micro-channels: Impacts of Flow Rate and Fuel Composition“. Energies 14, Nr. 14 (11.07.2021): 4190. http://dx.doi.org/10.3390/en14144190.

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Due to increasing demand for clean and green energy, a need exists for fuels with low emissions, such as synthetic gas (syngas), which exhibits excellent combustion properties and has demonstrated promise in low-emission energy production, especially at microscales. However, due to complicated flame properties in microscale systems, it is of utmost importance to describe syngas combustion and comprehend its properties with respect to its boundary and inlet conditions, and its geometric characteristics. The present work studied premixed syngas combustion in a two-dimensional channel, with a length of 20 mm and a half-width of 1 mm, using computational approaches. Specifically, a fixed temperature gradient was imposed at the upper wall, from 300 K at the inlet to 1500 K at the outlet, to preheat the mixture, accounting for the conjugate heat transfer through the walls. The detailed chemistry of the ignition process was imitated using the San Diego mechanism involving 46 species and 235 reactions. For the given boundary conditions, stoichiometric premixed syngas containing various compositions of carbon monoxide, methane, and hydrogen, over a range of inlet velocities, was simulated, and various combustion phenomena, such as ignition, flame stabilization, and flames with repeated extinction and ignition (FREI), were analyzed using different metrics. The flame stability and the ignition time were found to correlate with the inlet velocity for a given syngas mixture composition. Similarly, for a given inlet velocity, the correlation of the flame properties with respect to the syngas composition was further scrutinized.

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Minitsky, Anatoly, Nataliya Minitska, Oleksandr Okhrimenko und Dmytro Krasnovyd. „Determining the influence exerted by the static conditions of final squeezing on the compaction process of iron-based powder materials“. Eastern-European Journal of Enterprise Technologies 1, Nr. 1 (109) (19.02.2021): 63–68. http://dx.doi.org/10.15587/1729-4061.2021.224941.

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This paper reports a study into the process of re-compaction of powder briquettes in the conditions of static pressing at a pressure of 800 MPa. The technological parameters of the pressing process have been analyzed, which make it possible to improve the compaction of powder briquettes based on iron. Such parameters are the outer greasing, which reduces friction between a green compact and the walls of the press tool matrix, and the firing, which removes the deformation strengthening of the green compacts and increases their plasticity. The green compacts’ sealing mechanism involved in the final squeezing process has been established, which is associated with the grinding of pre-compressed particles due to the strain in the contact areas. The increase in the stressed state of green compacts following the final squeezing was confirmed by the results of studying the residual micro-strains. The change in the stressed state of iron green compacts has been confirmed by the study into the structurally sensitive characteristics, which include the materials’ magnetic and electrical properties. Determining the magnetic characteristics has shown that final squeezing leads to an increase in coercive force, which can be explained by both the increase in the stressed state and the grinding of grains. Investigating the impact exerted by the annealing environment on the value of magnetic characteristics has demonstrated that annealing in hydrogen is more effective in terms of improving magnetic properties than annealing in a vacuum. This is due to the refining of grain boundaries through the processes of reduction of oxide films. The study of the mechanical characteristics of green compact materials based on iron powder has established that final squeezing leads to an increase in the hardness and strength of materials depending on the conditions of deformation. A significant improvement in the green compacts’ strength (820‒824 MPa) is due to both a decrease in porosity by 8‒10 % and an increase in the contact area as a result of plastic deformation after the annealing

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Xu, Ming, Hanlin Wang, Mingxian Liu, Jianning Zhao, Yuqiong Zhang, Pingping Li, Mingliang Shi, Siqi Gong, Zhaohuan Zhang und Chufu Li. „Performance test of a 5 kW solid oxide fuel cell system under high fuel utilization with industrial fuel gas feeding“. International Journal of Coal Science & Technology 8, Nr. 3 (13.05.2021): 394–400. http://dx.doi.org/10.1007/s40789-021-00428-2.

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AbstractAs the demand for green energy with high efficiency and low carbon dioxide (CO2) emissions has increased, solid oxide fuel cells (SOFCs) have been intensively developed in recent years. Integrated gasification fuel cells (IGFCs) in particular show potential for large-scale power generation to further increase system efficiency. Thus, for commercial application of IGFCs, it is important to design reliable multi-stacks for large systems that show long-term stability and practical fuel gas for application to industrial equipment. In this work, a test rig (of a 5 kW SOFC system, with syngas from industrial gasifiers as fuel) was fabricated and subjected to long-term tests under high fuel utilization to investigate its performance. The maximum steady output power of the system was 5700 W using hydrogen and 5660 W using syngas and the maximum steady electrical efficiency was 61.24% while the fuel utilization efficiency was 89.25%. The test lasted for more than 500 h as the fuel utilization efficiency was larger than 83%. The performances of each stack tower were almost identical at both the initial stage and after long-term operation. After 500 h operation, the performances of the stack towers decreased only slightly under lower current and showed almost no change under high current. These results demonstrate the reliability of the multi-stack design and the prospect of this SOFC power-generation system for further enlarging its application in a MWth demonstration.

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ISHIMOTO, Yuki. „Green Hydrogen Energy System“. Journal of the Atomic Energy Society of Japan 54, Nr. 2 (2012): 110–14. http://dx.doi.org/10.3327/jaesjb.54.2_110.

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