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In the present study, we explored the temperature evolution and hydrogen desorption properties of the Mg50Ni50 alloy through both numerical simulation and experimental analyses. Desorption kinetics characterization was carried out using the volumetric method, specifically employing a Sievert's-type apparatus to investigate solid-gas reactions. The experiments covered a temperature range from 313 K to 353 K, with an initial hydrogen pressure of 12 bar. Simultaneously, a mathematical approach was employed to numerically investigate the temperature evolution within the hydride bed. Using COMSOL Multiphysics as a simulator, a numerical simulation was conducted based on experimental data. The study examined the impact of cooling temperature on hydride temperature evolution. Results revealed that hydrogen desorption kinetics of the amorphous Mg50Ni50 alloy are more significant compared to those of Mg2Ni compounds. Moreover, the effect of the warming temperature on the equilibrium pressure can also be observed in the hydrogen desorption isotherm curves. The experimental study of the Mg50Ni50 alloy provided activation energy data, along with determination of hydride formation enthalpy and entropy. On the other hand, we showed that the hydride temperature is maximum at the hydride-hydrogen interface within the hydride center.

In the present study, we explored the temperature evolution and hydrogen desorption properties of the Mg50Ni50 alloy through both numerical simulation and experimental analyses. Desorption kinetics characterization was carried out using the volumetric method, specifically employing a Sievert's-type apparatus to investigate solid-gas reactions. The experiments covered a temperature range from 313 K to 353 K, with an initial hydrogen pressure of 12 bar. Simultaneously, a mathematical approach was employed to numerically investigate the temperature evolution within the hydride bed. Using COMSOL Multiphysics as a simulator, a numerical simulation was conducted based on experimental data. The study examined the impact of cooling temperature on hydride temperature evolution. Results revealed that hydrogen desorption kinetics of the amorphous Mg50Ni50 alloy are more significant compared to those of Mg2Ni compounds. Moreover, the effect of the warming temperature on the equilibrium pressure can also be observed in the hydrogen desorption isotherm curves. The experimental study of the Mg50Ni50 alloy provided activation energy data, along with determination of hydride formation enthalpy and entropy. On the other hand, we showed that the hydride temperature is maximum at the hydride-hydrogen interface within the hydride center.

Cameroon faces enormous clean energy accessibility challenges despite abundant energy resources and huge quantities of free oil palm residues (OPR) generated but dumped yearly from the agro-industrial companies like the Cameroon Development Corporation (CDC). Presently, electricity supply is mainly from hydro (73 %) with accessibility of 65 % and 14 % for urban and rural areas respectively, while energy mix is historically dominated by traditional biomass fuels such as firewood and charcoal, accounting for more than 76 % of the country's total energy consumption. The hydro supply is not regular as it depends on weather conditions and this has negatively impacted the economy. The situation is aggravated by the increased energy demand over the past decade as Cameroon has engaged to become an emerging economy by 2035. However, encouraging policies for researchers and investors in the energy sector have been put in place with a view of attaining a 25 % share of renewable energy (RE) by 2035. OPR are a potential (RE) resource but require technical assessment and technological transformation into clean energy rather than dumping, which constitutes a serious environmental problem. This research has assessed the quantity of OPR generated annually at the CDC and estimated its clean energy value from 2004 to 2018 by consulting fruits-harvest records from CDC statistics office and by bomb calorimetry respectively. The significant findings reveal a yearly production of 203666T of OPR with a calorific value of 896 TJ, corresponding to electrical energy potential of 249 MWh. The energy could be used by the industry or injected into the grid to mitigate the current energy challenges.

Cameroon faces enormous clean energy accessibility challenges despite abundant energy resources and huge quantities of free oil palm residues (OPR) generated but dumped yearly from the agro-industrial companies like the Cameroon Development Corporation (CDC). Presently, electricity supply is mainly from hydro (73 %) with accessibility of 65 % and 14 % for urban and rural areas respectively, while energy mix is historically dominated by traditional biomass fuels such as firewood and charcoal, accounting for more than 76 % of the country's total energy consumption. The hydro supply is not regular as it depends on weather conditions and this has negatively impacted the economy. The situation is aggravated by the increased energy demand over the past decade as Cameroon has engaged to become an emerging economy by 2035. However, encouraging policies for researchers and investors in the energy sector have been put in place with a view of attaining a 25 % share of renewable energy (RE) by 2035. OPR are a potential (RE) resource but require technical assessment and technological transformation into clean energy rather than dumping, which constitutes a serious environmental problem. This research has assessed the quantity of OPR generated annually at the CDC and estimated its clean energy value from 2004 to 2018 by consulting fruits-harvest records from CDC statistics office and by bomb calorimetry respectively. The significant findings reveal a yearly production of 203666T of OPR with a calorific value of 896 TJ, corresponding to electrical energy potential of 249 MWh. The energy could be used by the industry or injected into the grid to mitigate the current energy challenges.

The synthesis, characterization, optimization and oxidation stability improvement of biodiesel from the seed oil of sesame indicum using a novel nano-heterogeneous bio-catalyst derived from the Chrysophyllum albidium seed coat (CASC) is reported. The heterogeneous catalyst was produced by calcination and activation at 400 °C, 600 °C and 800 °C using acetic acid. The catalyst was characterized using scanning electron monograph (SEM), Fourier transform infrared (FTIR), and x-ray diffraction (XRD). The seed oil was extracted using mechanical press milling and the biodiesel produced were characterized using AOAC 2019 edition and ASTM D-6151, Fourier transform infrared (FTIR) and gas chromatography (GC) methods. The results indicated that calcined Chrysophyllum albidum seed coat contains nano-particles and alkaline elements (75 % graphite). The calcination process improved the size reduction and structural arrangement of the particles. The 600 °C calcination temperature had the highest biodiesel yield of 88 % at 3.0 wt % catalyst concentration, 12:1 M ratio of alcohol to oil and 500 rpm. The reusability of catalyst indicated 71.50 % after fifth (5th) cycle. After 28 days storage duration in the presence of the natural, renewable and eco-friendly antioxidant (1 % turmeric), the oxidation instability of the produced biodiesel was reduced by 50 %. The quality of the biodiesel indicates agreement with standards and literature as well as high potential for effective application in diesel engine.

The synthesis, characterization, optimization and oxidation stability improvement of biodiesel from the seed oil of sesame indicum using a novel nano-heterogeneous bio-catalyst derived from the Chrysophyllum albidium seed coat (CASC) is reported. The heterogeneous catalyst was produced by calcination and activation at 400 °C, 600 °C and 800 °C using acetic acid. The catalyst was characterized using scanning electron monograph (SEM), Fourier transform infrared (FTIR), and x-ray diffraction (XRD). The seed oil was extracted using mechanical press milling and the biodiesel produced were characterized using AOAC 2019 edition and ASTM D-6151, Fourier transform infrared (FTIR) and gas chromatography (GC) methods. The results indicated that calcined Chrysophyllum albidum seed coat contains nano-particles and alkaline elements (75 % graphite). The calcination process improved the size reduction and structural arrangement of the particles. The 600 °C calcination temperature had the highest biodiesel yield of 88 % at 3.0 wt % catalyst concentration, 12:1 M ratio of alcohol to oil and 500 rpm. The reusability of catalyst indicated 71.50 % after fifth (5th) cycle. After 28 days storage duration in the presence of the natural, renewable and eco-friendly antioxidant (1 % turmeric), the oxidation instability of the produced biodiesel was reduced by 50 %. The quality of the biodiesel indicates agreement with standards and literature as well as high potential for effective application in diesel engine.

Solar photovoltaic (PV) projects are pivotal in addressing climate change and fostering a sustainable energy future. However, the complex landscape of renewable energy investments, characterized by high upfront costs, market uncertainties, and evolving technologies, demands innovative evaluation methods. The Real Options Approach has emerged as a powerful tool, offering strategic flexibility in decision-making under uncertainty. This paper comprehensively analyzes the application of real options for evaluating solar photovoltaic projects in 2008-2023. Analysis of document descriptors (author keywords, index keywords, and noun phrases extracted from titles and abstracts) reveals that the dominant research topics in the last ten years (2014-2023) include investment optimization, strategic analysis, energy policy, optimization of energy generation and investments in wind energy. These descriptors are used to analyze the evolution of research interests on a two-year basis and reveal the yearly evolution of the research topics. Finally, the concept of emergence is used to unveil emerging research trends, providing valuable insights for researchers and practitioners in the renewable energy sector. Ultimately, this work contributes to a deeper understanding of how real options analysis empowers decision-makers to make informed choices in advancing clean and sustainable energy solutions.