Globally, small and medium-sized enterprises (SMEs) mainly depend on the national grid to provide energy for their daily activities. The quality of energy supplied affects the operation of their appliances and work. In this study, an analysis has been conducted on the power quality of three different sources of energy: solar PV power only, hybrid solar PV–grid power, and national grid power only, and how they affect the operation of appliances in a laundry shop in Ghana. Data were obtained using data logs from a 5-kVA hybrid inverter setup with a 3-kW solar panel for 4 months. Electrical power quality parameters monitored were voltage level, frequency, power factor, sag/undervoltage, swell/overvoltage, voltage interruption, and flicker. The study revealed that operating a business on solar PV only assured the end user of the best electrical power quality. The hybrid solar PV–grid system is also a good candidate for bad weather where the solar PV would not be able to yield the expected energy. The national grid proved to be of lower quality and a potential hazard to appliances.

PurposeThis study has assessed the thermal performance of locally fabricated bio-based building envelopes made of coconut and corn husk composite bricks to reduce building wall heat transmission load and energy consumption towards green building adaptation.Design/methodology/approachSamples of coconut fiber (coir) and corn husk fiber bricks were fabricated and tested for their thermophysical properties using the Transient Plane Source (TPS) 2500s instrument. A simulation was conducted using Dynamic Energy Response of Building - Lunds Tekniska Hogskola (DEROB-LTH) to determine indoor temperature variation over 24 h. The time lag and decrement factor, two important parameters in evaluating building envelopes, were also determined.FindingsThe time lag of the bio-based composite building envelope was found to be in the range of 4.2–4.6 h for 100 mm thickness block and 10.64–11.5 h for 200 mm thickness block. The decrement factor was also determined to be in the range of 0.87–0.88. The bio-based composite building envelopes were able to maintain the indoor temperature of the model from 25.4 to 27.4 °C, providing a closely stable indoor thermal comfort despite varying outdoor temperatures. The temperature variation in 24 h, was very stable for about 8 h before a degree increment, providing a comfortable indoor temperature for occupants and the need not to rely on air conditions and other mechanical forms of cooling. Potential energy savings also peaked at 529.14 kWh per year.Practical implicationsThe findings of this study present opportunities to building developers and engineers in terms of selecting vernacular materials for building envelopes towards green building adaptation, energy savings, reduced construction costs and job creation.Originality/valueThis study presents for the first time, time lag and decrement factor for bio-based composite building envelopes for green building adaptation in hot climates, as found in Ghana.

Solar home systems (SHS) are increasing being deployed as sustainable energy supply for the residential sector to meet the Sustainable Development Goal 7 target by 2030, especially for countries in sub-Saharan Africa (SSA) where national grid electricity supply is inadequate or weak. For SHS in SSA, however, a unique challenge exists as many of the households do not have access to net-metering system that allows extra PV energy generation during the daytime to be exported to the grid. This leads to waste energy generation (redundant energy) when the household energy demand is lower than the PV energy generation. In this study, analysis has been conducted to determine the magnitude of redundant energy of 3 SHS. Hypothesis testing of the existence of redundant energy from the SHS is also conducted. Our study has revealed that generally, there is redundant energy generation in the hours of 10 a.m. to 3 p.m. for the households, with hourly values ranging from 0.37 kWh to 1.55 kWh. The redundant energy represents 29.6 %-56.3 % of the households' monthly PV energy generation. The findings of this study give insights into the potential of harnessing redundant energy of SHS for planning smart energy cities if net-metering systems were available.

Challenges related to sustainability, energy access, process efficiency, and cost of production in the extraction of palm oil make its energy analysis necessary in Ghana. This study determined the energy consumption patterns in palm oil mills in Ghana to ultimately enhance system efficiency and assess optimum production costs. In this study, data was collected among Palm Oil Processing facilities in Bono, Ashanti, Eastern and Western regions. The results found the average total energy consumption for the manual, semi-mechanised and highly mechanised extraction systems to be 122.5, 112.9, and 82.4 kJ/kg respectively. The net potential electricity from oil palm residue was estimated to be 299 kJ/kg which can be used for other operations. The mean total energy for the oil drying and pressing stages are identical across the systems. The minimum mean total energy is required at the threshing stage of the oil palm production process with which the manual system has the highest amount of energy whilst, the highly mechanized system requires the least average total energy for threshing. Policy makers should target increased level of mechanization since highly mechanized processing plants recorded lower energy demands.

This research article aims to explore the relationship between the machining parameters of a Slant Bed Turning Centre Computer Numerical Control (SB/C/CNC) precision lathe and surface microhardness, dimensional error and surface roughness of AL6061. A technique called the central composite design (CCD) method with 13 experiments was used to evaluate the surface microhardness, dimensional error, and surface roughness after a turning operation using a micro-grooved texture tool. Separate prediction models were developed for each of these characteristics using the response surface method (RSM) in order to find the optimal process parameters for each characteristic. The analysis of variance revealed that the prediction models for surface microhardness, dimensional error, and surface roughness were highly significant, with p-values less than 0.0001. The process parameters that resulted in the highest surface microhardness were a cutting speed (Vc) of 154.363 m/min and a feed rate (fz) of 0.231 mm/rev. On the other hand, the process parameters that led to the lowest dimensional error and surface roughness were Vc = 154.363 m/min, fz = 0.1389 mm/rev, and Vc = 152.081 m/min, fz = 0.1025 mm/rev, respectively. The multi-objective prediction model based on gray relational analysis showed an error range of 1.5% to 3.1% and a minimum gray relational degree value of 0.3503 within the feasible process parameter range. The accuracy of this multi-objective prediction model was higher, with a stronger response to the cutting speed Vc compared to the feed rate fz. The determined feasible process parameter range serves as a useful reference for engineers working with AL6061 materials in turning operations.

Honing is an abrasive superfinishing process essential for the cylinder bore/piston tribology, which in its turn affects the engine performance. This research article conducted post-treatment honing of the engine cylinder bore to remove slags produced by the laser surface texturing, reduce engine running-in time, and avoid abrasive wear. Optimization of the post-processing honing processing parameters by five factors and two levels of the orthogonal method was conducted to determine the suitable post-treatment honing parameters. Secondly, engine reverse dragging and bench tests were also performed with three different post-treated honed engines to explore the engine mechanical loss and fuel consumption. The engine dragging and bench test indicates that the two post-treated honed engines exhibited lower friction power, drag torque and fuel consumption than the standard engine. The post-treated honed engine 2 exhibited the best performance by reducing the reverse drag power and torque by 7.84 % and 7.69 %, respectively, when the engine speed was 1500 rpm. The curve of engine fuel consumption characteristics showed that both engine 1 and engine 2 significantly reduced the fuel consumption by 13 % and 15 % respectively, compared to the standard engine. The findings of this research will provide a further reference for the development of cylinder bores for improved engine efficiency.

The increasing effect of climate change as a result of CO2 emissions emanating from utilization of conventional energy resources is driving national and regional policies towards global energy transformation in all sectors, including the transportation sub-sector. Internal combustion engine vehicles (ICEV), which use fossil fuel are the main contributors of CO2 emissions in the transport sub-sector. Grid-powered battery electric vehicles (BEV) and solar electric vehicles (SEV) have the potential to reduce emissions in the transportation sub-sector and are therefore being promoted in regions where solar radiation levels are appreciable. Sub-Saharan Africa (SSA) is one of the regions that receives significant radiation levels compared to other parts of the world, however, countries in the sub-region are yet to tap into the enormous benefits of SEV. In this study, comparative lifecycle analysis has been conducted on the total cost of ownership (TCO) of Hyundai Ioniq (BEV), Sono Sion (SEV) and Toyota Corolla (ICEV) for commercial transport operations in SSA, with a case study in Ghana. Research was conducted on 100 drivers of 5-seater petrol/diesel light commercial vehicles (LCV) in the city of Accra and Kumasi. Data were taken on their driving profiles, average travel distance, fuel cost and maintenance cost. Their choices between ICEV, BEV and SEV were also ascertained. Our study revealed that 70% of LCV travel up to 300 km and below, daily. The total cost of ownership for LCV at an average annual travel distance of 60,000 km were 0.21 US$/km, 0.17 US$/km, 0.15 US$/km and 0.14 US$/km for Used-ICEV, New-ICEV, BEV and SEV for 20-year analysis period, respectively. The total cost savings with BEV and SEV usage are at least 28% and 34%, respectively, compared to traditional diesel or gasoline ICEVs. Payback periods for SEV and BEV compared to ICEV are 3.5 years and 4.5 years, respectively. Our study has revealed that there is potential emission savings of 70% and 75% for BEV and SEV, respectively, compared to ICEV. Finally, this study highlights that utilization of SEVs and BEVs for light vehicle commercial transportation in SSA can potentially lead to post-COVID recovery and growth in the sub-region, amidst increasing diesel and petrol prices for ICEVs.

Ghana has developed energy policies to help increase the use of renewable energy in its energy mix. With abundant water reservoirs and solar irradiation, the potential to deploy floating solar photovoltaic is feasible to increase the country's renewable electricity generation. RETScreen Expert software was used for studying a proposed FPV-Hydro hybrid plant system. This study conducted a feasibility analysis for a 420 MWp FPV on Akosombo Dam reservoir a location with 4.66 kWh/m2/day solar energy. The study recommended FPV power plant with capacity factor of 14.1%, and would consist of 500,000 units of solar panels covering a minimum area of 2,460,457 m2 to generate a total annual electricity of 520,233 MWh. The project will save 73,327 cubic metres of water from evaporating which can produce approximately 10 MWp hydroelectric power annually. FPV economic analysis shown that it will results in lower LCOE of US$ 0.10/kWh, annual revenue of USD $52,238,576.00 and 12-years simple payback time, indicating positive economic indicators. Additionally, it will significantly reduce GHG emissions by 308,904.5 tCO 2/MWh annually. The FPV-Hydropower hybrid plants prove feasible and contributes to a greener and less costly energy generation system to meeting the 10% additional Renewable Energy (RE) target of Ghana.

In this paper, studies have been conducted on the performance of solar PV modules with integration of four different thermal management (cooling) techniques, namely, perforated-ribs-heat-sink under natural convection (PRNC), phase change materials (PCM), galvanized duct with forced convection (GDFC), and ducted fins under forced convection (FDFC). Experiments were conducted with these four cooling techniques incorporated into the solar PV panels. The second law efficiency which measures the maximum possible energy output that can be obtained from the PV panel to that of the available exergy of the sun was used as the main performance metric for the analysis. The results obtained indicated average percentage improvement in second law efficiency of 0%, 33%, 53% and 72% for the PCM, PRNC, GDFC and FDFC, respectively, compared to the control PV module without any cooling technique. Analysis of the results also showed that, the PV panel integrated with FDFC can maintain more stable and relatively lower temperatures, averagely 39 °C. The stable temperature for the FDFC has the potential to minimize thermal stresses in the panel, thereby increasing its reliability and life-years. Finally, this study highlights that different levelized costs of energy (LCOEs) exist for solar PV panels incorporated with different cooling techniques.

Global level improvement of resource use efficiency in agro-ecosystems has always been the target of experts who are keen on reducing the environmental impact emanating from agriculture. To this end, energy audit analysis in agro-ecosystems to determine the energy use at the various subsectors and levels of the agricultural sector, including poultry birds production is crucial. Most of the energy analysis works in Ghana in the past were in the area of commercial buildings using traditional energy analyses approach. Little work has so far been done on energy analysis for poultry houses. EnergyPlus simulation of the ambient conditions and energy inputs were analysed and compared to the Artificial Neural Network (ANN) model to observe the performance of the ANN in predicting energy consumption. The annual energy consumption estimations were found to be 2,044 kWh and 1,452 kWh for lighting and equipment usage respectively. The model robustness checks showed that coefficient of determination values for training, validation, testing and overall were 0.95304, 0.9533, 0.9505 and 0.9527 respectively for each regression plot which shows that the ANN model was suitable for determining the energy consumption in a poultry production facility, and can be replicated for more refined predictions in Ghana.

The performance of solar PV panels is affected by the module temperature. Controlling the PV module temperature to optimize performance is of interest to researchers and project developers. In this paper, studies have been conducted on the performance of solar PV modules with integration of four different thermal management (cooling) techniques, namely, perforated-ribs-heat-sink under natural convection (PRNC), phase change materials (PCM), galvanized duct with forced convection (GDFC), and ducted fins under forced convection (FDFC). Experiments were conducted with these four cooling techniques incorporated into the solar PV panels, in a hot climate, Ghana. The results obtained indicated an average percentage improvement in second law efficiency of 9.0%, 18.5%, 30.3% and 45.5% for the GDFC, PRNC, PCM and FDFC, respectively, compared to the control PV module without any cooling technique. Analysis of the result also showed that for all the samples tested, the PV panel integrated with FDFC can maintain more stable and relatively lower temperatures, averagely 46 oC throughout the day. The stable temperature for the FDFC has the potential to minimize thermal stresses in the panel, thereby increasing its reliability and life-years. Finally, this study highlights that different LCOEs exist for solar PV plants incorporated with different cooling techniques.

Many households in sub-Saharan Africa (SSA) depend on wood-fuel and biomass for cooking, with associated health and negative environmental impacts. Indoor air pollution from these traditional cooking technologies and practices lead to a number of deaths each year. Clean and smokeless cooking technologies are necessary to minimize respiratory related infections associated with traditional cooking technologies. In addition, modern energy cooking services (MECS), which have lower levelized lifecycle cost have a part to play for post COVID recovery and growth in the sub-region. In this study, a novel pressurized solar electric cooker (PSEC) using diodes as the heating element has been constructed and tested in Kumasi city, Ghana. The PSEC comprises 150 Wp solar panel, 3.3 Liter cooking volume, and with the system integrated with PCM for thermal energy storage. From the experiments conducted in this study, the diode-heating element was able to charge the PCM (erythritol) and maintain it at an average temperature of 118 °C to cook rice, which is a common staple food enjoyed in many households in SSA. The result revealed that when the PCM integrated as energy storage medium was fully charged, the PSEC had fast cooking time of 50 min. Financial analysis also revealed that the PSEC has potential cost savings of US$ 575 and US$ 365, compared to cooking with charcoal and grid electricity, respectively, over a 10-year period.

The importance of parameters such as material type, compacting pressure, particle size, and their interactions in the manufacturing of charred briquette fuel for industrial and domestic use cannot be overemphasized because they have a considerable impact on briquette performance. In investigating the aforementioned phenomena, the Box–Behnken​ Response Surface Design and ANOVA were used to analyze how briquette material type, particle size, compacting pressure and their interactions significantly influence the mechanical and combustion properties of charred briquettes made from palm kernel shells, corn cobs, sawdust, and rice husk. All three factors namely material type, compacting pressure and particle size, with all possible interactions are significant determinants of the relax densities and impact resistance of all the briquette samples. Meanwhile, water resistance of the sampled briquettes was significantly different for material type, pressure level as well as particle size, however, all factor interactions were insignificantly affected with palm kernel shell and rice husk recording the highest and lowest water resistance property. With regards to the combustion properties, apart from material type which significantly affected heating rate and specific fuel consumption, pressure and particle size together with all interactions did not have any significant influence on heating rate and specific fuel consumption. Finally, the findings provide a new perspective to investigate other agricultural residues which will diversify the energy resources of the country.

The choice of feedstock for biogas production should not only be limited to organic waste like agricultural products, food, and animal waste. Human feces could also be considered a source of biogas production. The ever-increasing cost of fossil fuels and environmental pollution threats are forcing the search for alternative energy sources. Several types of research have to unlock the mysteries behind the difficulties of producing biogas from human feces, especially the production of more HN 3 , which is a greenhouse gas because of its low C:N ratio. This research experimentally investigated how to reduce their amount using rice straw with a high C:N ratio. Several combinations were made between the human waste and the rice straw at different ratios during the experiment. The result shows that the optimal outcome for methane production fell on the 50% HF and 50% RS combination due to the actions of both aerobic and anaerobic processes.

Community water supply systems in Ghana are grid connected which is intermittent leading to breakdown of the systems and causing water shortages. In addition, high electricity tariffs have led these systems into huge debts. This research, therefore, aims to conduct comparative assessment of adopting a hybrid grid-connected and a stand-alone power system for these systems, using HOMER pro software. A daily average of 121.25 kWh was obtained from the chosen site as an input. Two scenarios were considered: a Grid-PV (Scenario 1) and a PV-Genset (Scenario 2) hybrid systems. The grid-connected (Grid-PV) was the best option with a LCOE of $0.0824/kWh while the standalone (PV-Genset) system was $0.309/kWh. Comparing them with $0.233/kWh for the Grid-only system, the Grid-PV system was about 184% cheaper while the PV-Genset system was about 24% more expensive. The PW of the scenarios yielded $58,422 and -$43,371, an IRR of 15.3% and 1.6% and a SPP of 6.21 and 24.13 years respectively. Although Scenario 1 was economically viable for investment, it yielded the highest GHG emission of 12,341.5kg/yr. Scenario 2, on the other hand, was not an economically viable option but yielded the least GHG emission of 4775.57kg/yr. Although this system was relatively expensive from the financial point of view, environmental considerations together with the grid tariff evolution in its life-cycle will make it cheaper.

The present study is directed to the thermal, mechanical, and microstructure fields in the MAG surfacing welding remanufacturing for a worn-out tunnel boring machine disc cutter. For this purpose, a numerical model is established for the surfacing welding process based on the theory of temperature field and thermo-elastoplastic deformation. The effectiveness of the proposed model was verified by a single-pass single-layer surfacing experiment of the H13 steel sheet sample. The numerical simulation results reveal that the surfacing process's chan-ging trend and stress distribution are complex, and the surfacing layer has to undergo stress formation and release. The residual deformation is mainly concentrated in the surfacing layer and deforms specifically along with its thickness. The experimental results showed consistency with the simulated result, and the hardness of the surfacing layer is about 1.5 times that of the base material. The surfacing layer mainly comprises eutectic carbides V8C7 and SiC, and the secondary carbides are Cr23C6 and Cr7C3. This article's simulation results and experimental verification indicate that MAG surfacing welding is an effective method for the restoration (repair) of worn disc cutter. The remanufacturing process is technically sound and economically viable for tunnel construction.

Energy consumption in buildings especially in offices is alarming and prompts the desire for more energy analysis work to be done in testing models that can estimate the energy situation of commercial buildings, and the key contributing factors are based on human factors, work load, and weather variables like solar radiation and temperature. In the research, the administration block of the University of Energy and Natural Resources, Ghana, was selected and modeled for energy analysis using SketchUp. Daily energy consumption of the building was generated with EnergyPlus indicating the electricity consumption of the block for the year 2018 for which 68.7% was used by equipment in the block, 26.98% on cooling, and the rest on lighting. The Artificial Neural Network model which had weather variable and days as input neurons and cooling, lighting, equipment, and total building electricity consumption as output neurons was modeled in MATLAB. The model after training had R values for training, validation, and testing to be 0.999 and validation performance of 1.7∗10−04. It was able to predict the energy consumption for lighting, cooling, and equipment very close to the results with minimal. The results from the ANN model prediction were compared with the EnergyPlus simulations. The maximum deviation profile for the following parameters (lighting, cooling, and equipment) is 13%, 8%, and 4%, respectively. The large difference in the lighting and cooling is the difficulty involved in predicting human behaviour and weather conditions. The least value recorded for the equipment is due to its independence on external factors.

Devising technologies to make use of renewable energy such as solar energy is very innovative and progressive sincetapping energy from a free source is cost effective in the long-term and totally ecologically friendly. The main aim ofsolar drying of crops is to preserve them by removing the excess moisture that will cause their deterioration in orderto improve their shelf life. Solar drying though found to be a mature, cost-effective and an efficient method ofdrying especially crops, it has not been widely deployed for crop drying both at the commercial and industrial levelin Ghana. The purpose of this research is to produce a solar heat collector for space heating using cheap andavailable materials and also to demonstrate the importance of incorporating obstacle/fins on plates to improve theefficiency of solar collectors. This study investigates the effect of increased air contact area of various configurationon the efficiency of solar air heaters. Nine different absorber plates (with and without fins) were considered by thisresearch in an experimental study to select the best design that will be suitable for absorbing or providing a highfraction of heat for conditioning humid atmospheric air (lowest relative humidity of the collector air). The bestdesigns of this study had an efficiency between 58% to 72% and maximum absorber temperatures above 80oC,collector air temperature above 70oC and collector air relative humidity below 20% while the worst design had anefficiency between 35% and 50%, collector air temperature bellow 45oC and the lowest collector air relativehumidity of 26%. The findings of this research have revealed that increasing the contact area of the air current orcirculation and the shapes of the fins attached to flat absorber plates increase their air contact areas and affect thethermal efficiency of the solar collectors. Also, it has revealed that the arrangement of fins contributes positively tothe efficiency of solar collectors. Citation: Felix Uba, Eric Osei Essandoh, Gilbert Ayine Okolo, Charles Nunya Dzikunu. Thermal Performance of Flat PlateSolar Collectors for Humid and Unpredicted Weather using Air Properties and Energy Method, 2020; 5(4): 30-49. Received: September 17, 2020Accepted: December 31, 2020

Charred briquettes production is a sustainable way of producing cooking fuel from waste. Unsustainable harvesting of wood for fuel production has contributed immensely to the rapid deforestation in Ghana. This study determined the potential of charred briquettes of sawdust, rice and coconut husks in meeting cooking energy needs of households. In a further step, the acceptability of biomass users in the study to replace their current fuels with charred briquettes was established. The calorific value of the charred briquettes was found to be 24.69 MJ/kg. The highest combustion efficiency of briquettes was determined as 34.7% when a multi-feed gasifier stove (MFGS) was used. There were 14% and 80% reduction in particulate matter and carbon monoxide emissions, respectively when briquettes was used instead of charcoal in the MFGS. The analysis of the production cost of briquettes revealed that 1 kg of briquettes should be sold at Gh¢ 2.48 in order to make a 10% profit. The user acceptability survey indicated that about 40% of respondents are ready to patronize briquettes should it be sold at Gh¢ 2.48. This study established that briquette is a suitable replacement for wood and charcoal, if its full potential is harnessed and the energy utilization efficiency of biomass (sawdust, rice and coconut husts) briquettes is confirmed.