Abstract: The pursuit of middle-income economic status by Ghana comes with an associated increase in electricity and energy demand. Meanwhile, an increase in either electricity or energy consumption is likely to result in greenhouse gas (GHG) emissions as a result of increasing reliance on fossil fuel consumption. Presently, there is evidence of the impact of climate change on various aspects of Ghana’s socio-economic structures such as energy production, agriculture, and forestry. Therefore, it is imperative to develop and implement a long-term low-carbon sustainable energy supply strategy that will support the electricity demand of the major economic ambitions envisaged. This study applied a quantitative modelling and simulation methodology using the Model for Energy Supply Strategy and their General Environmental Impacts (MESSAGE) analytical tool to analyse the electricity generation system and the impact of fuel options on the environment. It was found that the inclusion of low-carbon emission energy conversion technologies such as renewables and nuclear energy is critical to curtailing carbon dioxide (CO2) emissions in Ghana’s energy sector. Therefore, the incorporation of climate-friendly energy sources into the electricity sector is necessary to achieve sustainable, resilient, and clean electricity generation. Ghana’s fulfilment of its international commitment to climate change depends on reducing its dependence on fossil fuels for electricity generation, thus, exploring the inclusion of zero-emitting sources into the country’s energy mix. PubDate: Tue, 26 Apr 2022 04:35:00 +000
Abstract: In Ethiopia, in addition to the large quantity of biomass consumption per year for daily cooking, production of the traditional local “Areke” consumes large amounts of fire wood which further accelerates deforestation. This study introduces solar-based technology for distillation of the local “Areke” using an indirect heating system. A solar parabolic dish collector with an aperture diameter of 0.9 m and an improved truncated cone cavity absorber were installed. The heat transfer process is governed by the principle of natural circulation, boiling, and condensation between a receiver and a distillation column. The experiment was conducted in Debre Birhan city at 20°C ambient temperature and atmospheric pressure of 0.722 atm. The surface temperature of the truncated cone cavity absorber attained a maximum temperature of 300.3°C, and the thermal efficiency attained by the collector was 54.6%. The production efficiency of the solar thermal local alcohol “Areke” distillation system was found to increase by 1.67% compared to the traditional firewood distillation system. PubDate: Mon, 11 Apr 2022 09:05:02 +000
Abstract: Proper management and effective conversion of biomass residues for biofuel production are crucial to reduce deforestation due to the cutting of trees for cooking and heating as a primary source of fuel and improving energy utilization of households. Thus, this study is aimed at investigating the effects of biomass residues of the coffee husk (CH), sawdust (SD), khat waste (KW), and dry grass (DG) and binding materials prepared from the waste paper pulp (PP) and clay soil (CS) under a low-pressure piston press densification machine. The biomass waste and binders were combined in a 3 : 1 ratio of CH : PP, CH : CS, SD : PP, SD : CS, KW : PP, KW : CS, DG : PP, and DG : CS. The briquettes were produced using a manually operated closed-end piston press machine compacted at an average pressure of 2 MPa. Briquette proximate and ultimate analysis of moisture content, volatile matter, fixed carbon, and ash content was determined using standard ASTM methods, while the calorific value was determined using a bomb calorimeter and data analysis was carried out using the R-program. Results revealed that the briquette produced from biomass residues has a mean value of fixed carbon and calorific value that ranged from to and cal/g to cal/g, respectively. Generally, briquettes produced from saw dust residue and the paper pulp binder had better quality of fuel and this could be used as an alternative source of energy and proper waste management option. PubDate: Thu, 31 Mar 2022 06:35:01 +000
Abstract: Used tyres are not biodegradable, and the current methods of disposal pose a threat to the environment. Such tyres can be valorised through decomposition to produce liquid fuel, an alternative diesel fuel, using thermal pyrolysis technique. Microwave pyrolysis is an alternate method which uses microwave irradiation, saves energy, and is better environmentally. The main objective of this study was to perform microwave pyrolysis of used tyres to produce liquid fuel and compare with thermal pyrolysis. The specific objectives were to study the effects of pyrolysis operating variables and optimization of liquid fuel yield for thermal pyrolysis, compare with microwave pyrolysis, and characterize the liquid fuel. Thermal pyrolysis variables were reaction temperature, reaction time, and particle size. Thermal pyrolysis reaction temperatures were 200, 300, 400, 500, 600, and 700°C; reaction time 10, 20, 30, 40, 50, 60, 70, 80, 100, and 120 minutes. Particle sizes were 25, 50, 60, 100, 125, and 200mm2. Thermal pyrolysis was carried out in furnace fabricated using furnace clay rated 600 W. A 500 ml round bottomed flask was used as a reactor. Design Expert 13 was used for data analysis and optimization, gas chromatography–mass spectrometry (GC-MS) was used for chemical composition analysis, while physiochemical properties were tested using standard methods. The yield of the liquid product was correlated as a quadratic function of the reaction variables. Response surface methodology (RSM) was used to study the effects of operating variables and identify points of optimal yields. The yield decreased as particle size increased. Yield increased with increase in temperature optima being 500°C. Yield increased with increase in reaction time, and the pyrolysis time was 80 minutes. The highest liquid yield of 40.4 wt. % corresponded to temperature of 500°C, time of 80 min for 60 mm2 size. The calorific value for liquid fuel was 47.31 MJ/kg and GC-MS analysis showed that the oil comprised of complex mixtures of organic compounds with limonene, toluene, and xylene as major components. When compared to the published literature on microwave pyrolysis, both processes gave similar maximum yield but microwave process was superior due to a 77.5% reduction in reaction time, resulting in a 73.02% saving in energy requirement. PubDate: Sat, 12 Mar 2022 08:35:01 +000
Abstract: The study is aimed at evaluating the availability of agriculture residues for syngas production, a case study for Sudan. 10 types of biomass are investigated: sugarcane (bagasse), cotton stalks, sesame straw, groundnut shells, maize straw, sorghum straw, millet straw, sunflower husks, wheat straw, and banana leaves. The available biomass is about 11 Mt/year (3.68 Mtoe). Aspen plus software is applied to simulate the gasification process. The study covered a wide range of operating conditions of steam to biomass ratio () and equivalent ratio (). For all types of syngas characteristics, H2 is 0.32-0.42 (mole fraction), CO is 0.13 to 0.16 (mole fraction), LHV is 5.0 to 8.0 MJ/kg, and the yield is ≥1.5. Wheat, groundnut, and sunflower have the best characteristics, while millet and bagasse yield the poorest characteristics. In addition, all types of syngas have except Millet. These characteristics make all types of syngas except millet suitable for both energy and industry applications. The potential syngas production is 14.17 Mt/year. PubDate: Mon, 21 Feb 2022 12:20:02 +000
Abstract: This study is aimed at determining the piezoelectric configuration for generating electricity from wave power through the design of a prototype model named Cov-TOTal. The study was carried out in Tomini Bay, Lopo Village, Batudaa Pantai District, Gorontalo Regency, located at approximately ±50 meters from the shoreline, while the piezoelectric construction was arranged in parallel with varying numbers of 28, 70, and 90 pieces. The result showed that the amount of piezoelectric configuration affects the value of the voltage and electric current generated by the Cov-TOTal model. Furthermore, the average electric voltage values were 17.58, 20.76, and 29.85 volts, while the average current was 1.16, 1.73, and 2.01 mA for each piezoelectric amount. Therefore, the largest values of power and electrical energy for each piezoelectric are 16.65 mW and 0.56 joules, 31.82 mW and 1.20 joules, and 44.59 mW and 1.77 joules, respectively. This study concluded that the amount of piezoelectric configuration has a significant effect on the voltage, current, power, and electrical energy produced. PubDate: Mon, 27 Dec 2021 11:35:06 +000
Abstract: Used tyres pose a threat to the environment, especially in developing countries, since the current disposal methods lead to environmental pollution. Pyrolysis liquid from used tyres can be used as a source of fuel to replace petroleum diesel. Microwave pyrolysis is an alternative valorization process that is supposed to save energy and, therefore, is environment friendly. In the current study, microwave pyrolysis was used to produce liquid fuel. Processing variable levels for microwave were power levels of 20, 30, 40, 50, 60, 80, and 100%; the reaction times were 8, 13, 18, 23, and 28 minutes; and the particle sizes were 25, 50, 100, and 200 mm2. Design-Expert 13 was used for data analysis and optimization, and GC-MS was used for chemical composition analysis, while physiochemical properties were tested using standard methods. Response surface methodology (RSM) was used to study the effects of operating variables and identify the points of optimal yields. For microwave pyrolysis, the highest liquid yield of 39.1 wt. % was at 50% power, 18 min reaction time, and particle size of 25 mm2. The yield decreased as the particle size increased. RSM gave conditions for optima in agreement with the experimental results. The calorific value for liquid fuel was 48.99 MJ/kg. GC-MS analysis showed that the oil comprised complex mixtures of organic compounds with limonene, toluene, and xylene as major components. The liquid fuel properties meet the required international standards and can be used as an alternative to diesel fuel. PubDate: Wed, 11 Aug 2021 13:35:07 +000
Abstract: Background. Global warming is a growing threat in the world today mainly due to the emission of CO2 caused by the burning of fossil fuel. Consequently, countries are being forced to seek potential alternative sources of energy such as wind, solar, and photovoltaic among many others. However, the realization of their benefits is faced with challenges. Though wind stands a chance to solve this problem, the lack of adequate site profiles, long-term behavioural information, and specific data information that enables informed choice on site selection, turbine selection, and expected power output has remained a challenge to its exploitation. In this research, Weibull and Rayleigh models are adopted. Wind speeds were analyzed and characterized in the short term and then simulated for a long-term measured hourly series data of daily wind speeds at a height of 10 m. The analysis included daily wind data which was grouped into discrete data and then calculated to represent the mean wind speed, diurnal variations, daily variations, and monthly variations. To verify the models, statistical tools of Chi square, RMSE, MBE, and correlational coefficient were applied. Also, the method of measure, correlate, and predict was adopted to check for the reliability of the data used. The wind speed frequency distribution at the height of 10 m was found to be 2.9 ms-1 with a standard deviation of 1.5. From the six months’ experiments, averages of wind speeds at hub heights of 10 m were calculated and found to be 1.7 m/s, 2.4 m/s, and 1.3 m/s, for Ikobe, Kisii University, and Nyamecheo stations, respectively. The wind power density of the region was found to be 29 W/m2. By a narrow margin, Rayleigh proves to be a better method over Weibull in predicting wind power density in the region. Wind speeds at the site are noted to be decreasing over the years. The region is shown as marginal on extrapolation to 30 m for wind energy generation hence adequate for nongrid connected electrical and mechanical applications. The strong correlation between the site wind profiles proves data reliability. The gradual decrease of wind power over the years calls for attention. PubDate: Wed, 23 Jun 2021 09:20:01 +000
Abstract: This paper presents new evidence supporting the development of a screening threshold to evaluate the impact aggregations of solar PV facilities in the northeastern United States can have on voltage deviations in the distribution grid (often called flicker). Using measurements from solar irradiance meters and customer-sited monitoring equipment for residential and light commercial solar systems in Central New York along with data from the Measurement and Instrumentation Data Centers at the Oak Ridge National Laboratory, Elizabeth City State University, and Bluefield College, we present multiple lines of support for the adoption of a flicker screening threshold equivalent to a 5% change in voltage resulting from a full-on to full-off transition of a solar facility. This approach is based on both the newer flicker perception limits in IEEE 1453-2015 and the previous limits derived from the flicker curves in IEEE 519-1992 and is consistent with recent draft recommendations from the Electric Power Research Institute (EPRI) for use in New York. Measurements of correlations between fluctuations at different sites along with a model for high densities of solar facilities are applied to allow the impact of multiple systems on a single feeder to be taken into account while maintaining the simplicity of a single screening threshold. PubDate: Tue, 01 Jun 2021 06:20:01 +000
Abstract: Energy situation in Malawi is continuing facing critical challenges to satisfy the existing demand. However, energy consumption and energy conservation studies have been neglected to help overcome this problem. In this paper, electric energy audit was conducted for a commercial building in Mchinji, Malawi, in order to identify energy-saving opportunities. The study employed a mixed method research which involved a series of surveys, observation, data collection, and analysis. The current energy consumption was determined and compared with the proposed energy consumption after replacing some equipment. The proposed system saved up to 33.46% of energy. The study also suggested behavior change towards energy saving. Additionally, an alternative energy system was also suggested. Thus, the HOMER software was employed to design, optimize, and analyze a solar-battery-grid-connected energy system. The proposed system has a simple payback period of 9.8 years. The system’s cost of energy was estimated as 0.0372 $/kWh, and the capital cost was $ 150,887. PubDate: Tue, 18 May 2021 10:05:01 +000
Abstract: Biogas is environmentally sound and economically viable, clean, and renewable energy source. Despite its numerous benefits and dissemination efforts, the adoption of biogas technology has been low. The objective of this study was to assess factors determining adoption of biogas technology as an alternative energy source at household level in Aleta Wondo district, southern Ethiopia. A multistage sampling technique was employed to select sample households. A total of 148 sample households, 51 biogas technology adopters, and 97 nonadopter households were surveyed. The collected data were analyzed by inferential statistics and econometric model using STATA version 13.1. Results from the probit model showed that education level of household head, annual income level, livestock holding size, access to technical support, and level of awareness have significant positive influence on households’ decision to adopt biogas technology. Other factors include poor performance of biogas plants associated to technical problems, and high installation costs unaffordable to the majority of rural population had a negative implication in adoption process. These are also the factors contributing to low adoption. Therefore, raising the population awareness on the benefits of biogas and assigning the biogas technicians who can give immediate maintenance services at “Kebele” level could extend the biogas technology. PubDate: Wed, 21 Apr 2021 13:50:00 +000
Abstract: Recently, the technology of floating photovoltaic panels has demonstrated several advantages over land installations, including faster deployment, less maintenance cost, and higher efficiency. Lake Nasser is the second largest man-made freshwater lake in the world with a surface area of almost 5000 square km. Being in one of the hottest areas in the world, evaporation of water causes loss of very precious and scarce resources: freshwater. Fortunately, the lake is also located in a very rich area in solar energy. This paper presents a study to utilize Lake Nasser’s surface for massive production of solar energy, while significantly reducing the loss of water by evaporation from the lake surface. The project has the potential to be one of the largest producers of low-cost clean electric energy in the world for Europe and the Middle East and North Africa (MENA) region, especially with the ongoing efforts to connect the North African countries with the European super power grid. The study shows that the first phase of the project is expected to deliver about 16% of European need of electricity and save about 3 billion m3 of freshwater. The subsequent phases will provide low-cost green energy to replace the combustible fuels in Europe by 2045, while saving up to 10-12 billion m3 of freshwater lost by evaporation from Lake Nasser. PubDate: Tue, 13 Apr 2021 02:05:01 +000
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