Abstract: Publication year: 2020Source: Energy and Power, Volume 10, Number 2Sunday Yusuf Kpalo, Mohamad Faiz ZainuddinIn Nasarawa state, over 70% of the population are involved in subsistence farming. Varied agricultural resources are produced in millions of tons annually. Large quantity of residues is generated that are either left to rot on farmlands or disposed of by burning in open air. In many rural areas, the residues are also used in their raw form for cooking purposes which is inefficient. The disposal and use of the residues cause pollution in the environment which affects human health. Residues can provide a source of clean and renewable energy in the form of solid biofuel called briquettes through densification. Briquetting is a densification technology that converts residues with a low heating value per unit volume into high density and energy concentrated fuels. This paper offers a perspective on the potentials of agricultural residues in Nasarawa state to produce briquettes as an alternative clean and sustainable domestic cooking fuel. The paper concludes that briquettes could be economically and environmentally friendly alternative to fuelwood. The use of biomass briquettes would reduce dependence on fuelwood, environmental pollution and the amount of time spent on cooking. Adopting the briquetting technology will enhance access to clean and affordable energy in line with the 7th goal of the United Nation’s Sustainable Development Goals.
Abstract: Publication year: 2020Source: Energy and Power, Volume 10, Number 2M. Marouf WaniThis paper presents the results of the CFD research investigations on a single cylinder spark ignition engine modeled alternatively with a digital intake valve and a cam based intake valve. The results were computed in the thermodynamic simulation software AVL BOOST. The software uses the finite volume method along with the conservation equations of mass, momentum, energy and the equation of state for an ideal gas. The parameters computed were pressure, velocity, density and temperature etc. The emissions and performance parameters of the engine were simulated for both the conventional cam based valve and the digital valve. The digital intake valve was modeled for a constant maximum valve lift throughout the intake process where as the conventional cam based valve was modeled for variable valve lift on a crank angle to crank angle basis. The results showed that the engine with the digital intake valve gave better volumetric efficiency, power, torque and brake specific fuel consumption as compared to the engine using the conventional cam based valve. Further the engine with digital intake valve has better emissions characteristics as compared to the engine with cam based valve.
Abstract: Publication year: 2020Source: Energy and Power, Volume 10, Number 2Yehya AmariWhat is known as banding energy is in fact the energy needed to separate atoms, the real banding energy is match more than this; it is the energy that holds atoms together despite the permanent vibration. This work is in continuity with previous ones that predict the same thing. This work is an analysis that ends with a proposal as a solution for the problem of energy and it sources. Characteristics of the electron (Size and Speed ...) were placed in the law of magnetic field; this led to one of most verified laws of electricity, which is the Coulomb low. Basing on this result, another real parameter which is relativity of the physical quantities was introduced by the replacement of what led to the Coulomb force. All this brought us to the conclusion that justifies the behavior of the mater, it is the existence of the Infinite Energy.
Abstract: Publication year: 2020Source: Energy and Power, Volume 10, Number 1Abdu Zubairu, Abddullahi S. B. Gimba, Babagan Gutti, Abddulmalik AuduA p-n homo-junction copper (I) oxide (cuprous oxide, Cu2O) solar cell was potentio-statically electro-deposited on an FTO (Fluorine Tin Oxide)-coated glass substrate from a solution containing 0.4M copper (II) sulfate and 3M lactic acid. The deposition was carried out in two stages: in the first stage, n-type cuprous oxide was deposited on the FTO glass substrate using a solution with bath pH of 7.5, and at a constant potential of -0.20V (vs. Ag/AgCl/saturated NaCl) to give a thickness of 16000 Angstrom (1.6µm). While the second stage was characterized with the deposition of a 13000 Angstrom (1.3µm) layer of layer p-type cuprous oxide directly on the already deposited n-cuprous oxide, at a solution pH of 11.56, and applied potential of -0.4V throughout. Bath temperature was maintained at 60°C throughout the deposition processes with continuous stirring. The lactic acid was used to stabilize Cu (II) ions at bath pH higher than 7, while the bath pH was carefully adjusted by the controlled addition of 4M NaOH. The superstrate solar cell configuration has the added advantage of not only serving as a supporting structure, but also as a window for the illumination and as part of the encapsulation. The electrical, structural, and optical characteristics of the cell were well investigated, where values of 0.60mA, 0.453mV, 0.272mW, 0.155mW, 0.336mV, 0.462mA, 0.571 and 0.058% were recorded for the short-circuit current density (JSC), open-circuit voltage (VOC), theoretical power (PTh), maximum power (PMAX), maximum voltage (VMAX), and maximum current (IMAX), fill factor (FF), and efficiency respectively.
Abstract: Publication year: 2020Source: Energy and Power, Volume 10, Number 1Clement Malanda, Augustine B. Makokha, Charles Nzila, Collen ZalengeraOff-grid villages in Malawi continue to suffer from limited access to electricity due to under performance of the installed generation systems. This is largely attributable to inappropriate methodologies applied for sizing the systems that ignore sustainability indicators (technical, economic and environmental) as well as communities’ existing energy demand and future projections. This paper presents the sustainability evaluation of five types of hybrid renewable energy systems considered for deployment in three villages in Malawi. The study employed a Multi-Criteria Decision Analysis (MCDA) based on TOPSIS (Technique for Order of Preference by Similarity to the Ideal Solution) algorithm. The PV-Battery (PB), PV-Wind-Battery (PWB), PV-Diesel-Battery (PDB), Wind-Diesel-Battery (WDB) and PV-Wind-Diesel-Battery (PWDB) systems were evaluated. The study envisaged to identify suitable systems for deployment in each of the villages based on the pre-set technical, economic and environmental criteria. Under these criteria, the sub-criteria were identified which included; renewable fraction, excess electricity, total system capacity, battery autonomy, total electrical production, return on investment, simple payback, Net Present Cost (NPC), initial capital cost, operating cost, Cost of Energy (COE) and carbon dioxide (CO2) emissions. The indicative values for these sub-criteria were derived from the optimization results from HOMER simulation software. The TOPSIS analysis entailed definition of energy alternatives and criteria, formulation of the decision matrices, normalization of the decision matrices, generation of weighted normalized matrices, determination of ideal and negative ideal solutions, calculation of relative separations from the ideal and negative ideal solutions and determination of relative closeness of each energy alternative to the ideal solution. For Chigunda, the PWB system was the most suitable with the highest closeness to ideal solution (Ci) value of 0.749 while for Mdyaka and Kadzuwa; the best alternative was the PB configuration with the highest Ci values of 0.708 and 0.717 respectively.
Abstract: Publication year: 2020Source: Energy and Power, Volume 10, Number 1Kamdem K. Claude Aurélien, Zhu Xiaolu, Harouna K. Attaher, Holman Joseph B., Alaeldin Mohamed TairabNowadays, the possibility of substituting gasoline fuel with biofuels is examined by numerous researchers. This paper discusses the numerical study of the biofuel model (methyl decanoate). The Fluent code was used to validate the comparison between the non-premixed gasoline (n-decane) and biofuel model (methyl decanoate) combustion in the same conditions. The turbulence model used was the realizable k-ε model. The aerothermochemistry equations and the transport model of chemical species (Eddy-dissipation) were implemented in the combustion reaction to develop the velocity, pressure, temperature, energy, enthalpy, the turbulence dissipation rate, the kinetic energy of the turbulence, and the mass fraction of the species. The results showed that the CO2 and NOX contents of methyl decanoate are 5.7% and 11.03% respectively higher than those of decane.
Abstract: Publication year: 2019Source: Energy and Power, Volume 9, Number 2L. Zhang, R. E. BlanchardThis paper adapts the ethanol model developed by Aldonza and Blanchard1 by applying it to maize feedstock in China. Part of the reasoning for this is according to the BP Statistical Review of World Energy 20182, the proven oil reserves in China only accounted for 1.5% of the world reserves in 2017. Meanwhile, Chinese energy demand has soared as a result of rapid economic growth. Dependence on imported oil and serious environmental pollution have forced the government to give priority to energy security issues and actively develop its renewable energy industries. China is a populous country with around 40% of the population living in rural areas. It might be significantly important for the goal of sustainable energy to establish self-sufficient bioethanol manufacturing plants in areas with high agricultural output. This study will predict the potential of an inedible maize-based ethanol plant in a rural area of Heilongjiang Province, China, which can save on transportation costs as well as a benefiting from a large source of raw materials, consisting of degraded stored maize kernels and maize cobs. The estimated operating time is 20 years and the annual throughput of maize is 3650 tons. The prospective ethanol yield is 1800 litres/day with a yield of 0.18 litres per kilogram of maize kernels. Meanwhile, solar energy would be fully utilized to exchange heat with the puree to reach the chemical reaction temperature. The double enzyme process and three consecutive processes of fermentation is used in the ethanol production system. It is concluded that the plant model would recover investment funds in 6 years under government’s tax incentives. The sensitivity analysis for estimated cash flows indicated that the annual yield and retail price of ethanol to be the highest risks of this enterprise.
Abstract: Publication year: 2019Source: Energy and Power, Volume 9, Number 1M. Marouf WaniThis paper presents the octane demand based methodology for designing a spark ignition engine for any suitable S.I engine fuel alternatively for maximum performance and minimum CO emissions. An example of designing a single cylinder 4 stroke cycle spark ignition engine alternatively for maximum performance and minimum CO emissions is given in this paper. The computational design investigations were done in the professional internal combustion engines simulation software, AVL BOOST. The design of the software is based on conservation laws for mass, momentum and energy. The software uses the numerical finite volume method to solve thermodynamic equations for computing various thermodynamic properties. The computational simulations were done to ensure that the octane demand of the engine does not exceed the octane number of any commercially available gasoline for each case of engine design. The compression ratio and spark timing based start of combustion timing of the engine were optimized to redesign the existing engine with better performance for a market need based engine with minimum CO emissions. The results showed that it was possible to redesign the existing engine with better performance for an engine with minimum CO emissions while maintaining the maximum octane demand of the engine within the octane number of the commercially available gasoline. It was also observed that engine designed for minimum CO emissions shows a drop in HC emissions as well. However there was an increase in the level of NOx emissions produced by this engine. The performance of the engine designed for minimum CO emissions was satisfactory when compared with the engine producing higher power.
Abstract: Publication year: 2019Source: Energy and Power, Volume 9, Number 1E. C. Merem, Y. Twumasi, J. Wesley, D. Olagbegi, S. Fageir, M. Crisler, C. Romorno, M. Alsarari, A. Hines, G. S. Ochai, E. Nwagboso, S. Leggett, D. Foster, V. Purry, J. WashingtonBeing an emerging economy where the dependence on geothermal power to sustain production over the years in the country ranks high, Kenya’s Rift Valley contains substantial geothermal energy enough to power the economy than most African countries. In the last several years, geothermal production has gained steam, and this has resulted in an unprecedented surge in installed capacity in different sites amid rising demands. This coincides with allocations to optimize the growth of the sector and the investments to boost supply among renewables. With that has come joint ventures and growing prospects in the sector likely to extend into the upcoming decades. Of great significance is the uptick in geothermal power output and its emergence as the second largest source of renewables alongside infrastructure proliferation. While this reflects the profile of Kenya as a major producer worldwide, geothermal power continues to serve the nation through improved access to electricity for communities and firms as clean source of energy with low carbon foot print and limited environmental impacts due to many factors. Considering the rising usage and the role of Kenya as regional leader in geothermal energy output, very little has been done in the literature to assess current capacities and the state of the resource. Added to that, previous studies overlooked the use of mix model in tracking the status and evolving patterns of geothermal parameters from production to installed capacities in the country. This paper will fill that void by analyzing geothermal energy use in the East African Nation of Kenya. Emphases are on the issues, trends, impacts, production, factors and current efforts to boost production. Using mix scale methods of GIS and descriptive statistics, the results show changes in usage, rising production in geothermal energy and spatial dispersal of various indicators from assets to elevation along the Rift Valley. With the emergent trends attributed to socio-economic and physical factors, the paper recommended the need for education, support for energy infrastructure development, spatial analysis and the design of a regional geothermal energy information atlas.
Abstract: Publication year: 2019Source: Energy and Power, Volume 9, Number 1Quiroga N. V., Esteves A., Bailey J., Esteban S.Solar energy for cooking is an interesting option to achieve energy efficient cooking, while reducing environmental impact and facilitating nutritious cooking on a daily basis, especially to provide nutrition for young children. Solar oven delivers high thermal performance running on solar energy alone on clear days. On cloudy days, the amount of solar energy is not enough to use the solar oven. Therefore, it is necessary to cook with electricity, gas or firewood, which breaks the continuity of the use of the solar oven. Then, when it is possible to use the solar oven again (on the subsequent clear day), it is difficult because of the habit established of fuel use. The hybrid oven (solar + biomass) allows for cooking every day of the year (clear or cloudy), with the same device, even at night. This paper presents the design, construction and thermal evaluation of a hybrid solar oven with biomass as an auxiliary source of energy. The basis is the drum solar oven, widely used for its characteristics: easy to build, efficient performance and optimum cooking capacity. It incorporates a specially designed appliance which takes advantage of the biomass and generates energy efficient cooking. Thermal tests are carried out to determine the characteristic parameters: figures of Merit F1 =0.100; F2 =0.253, standardized cooking power for 50°C, 31.2 W, and cooking efficiency 23.3% for operation only with solar energy and standardized cooking power for 50°C, 378.3W and cooking efficiency 5.8% for the oven with hybrid operation. Temperatures reached by the absorber plate are 120°C for solar-only energy operation and 173°C for hybrid operation. These temperatures do not endanger the integrity of the materials used. Only a minimum amount of energy is needed to reach the necessary temperature and power for cooking. It is therefore an interesting and economical solution for all communities of any climatic condition, especially those that are isolated from energy supply networks.
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