Viability of non-edible oilseed plants and agricultural wastes as feedstock for biofuels production: A techno-economic review from an African perspective

This research articles was published in Journals Biofuels Bioproducts& Biorefining Volume 17, Issue 5,2023Given the benefits of biofuels over conventional fuels, there is concern that widespread production of biofuels from edible feedstocks to meet demand will lead to food insecurity and other socioeconomic challenges. Thus, the goal of this research is to look into the techno-economic potential of non-edible oilseed plants and agricultural wastes as primary feedstocks for biofuel production in Africa. The inability of biofuel to cope in the fuel market has been demonstrated to be due to the high production costs, which limit profitability because the end price is heavily influenced by that of conventional fuel. However, the high production costs are entirely due not only to components such as feedstock, conversion processes, and infrastructure but also to a lack of techno-economic assessment (TEA). African biofuel production can be competitively industrialized through the adoption of strong supportive policies and programs. Adoption of these policies and programs is critical for capitalizing on the benefits of non-edible feedstocks in biofuel production while also boosting rural development through job creation. Techno-economic assessment of conversion processes and infrastructure is recommended to provide a clear picture of the techno-economic aspects, serving as a blueprint for the design of biofuel production facilities. Further, TEA has been shown to be a useful tool in the development process of new technologies aimed at lowering overall production costs and making biofuel more affordable. The combination of TEA and enabling policies and programs will increase the price competitiveness of biofuels, allowing them to capture a sizable share of the fuel market. © 2023 Society of Industrial Chemistry and John Wiley & Sons Ltd

Techno-economic evaluation of transesterification processes for biodiesel production from low quality non-edible feedstocks: Process design and simulation

This research article was published by ELSEVIER, Volume 297, 2024The global demand for fossil fuels has led to increased pollutant emissions and depleted fossil fuel resources. Biodiesel, a fossil fuel alternative, is widely produced via transesterification. This study assesses the techno-economic performances of three transesterification processes (alkaline, acid, and CaO catalytic) for biodiesel production from low-quality non-edible feedstocks. The study explores effects of elevated free fatty acids (FFAs) and oil/ethanol flow rates on these processes, focusing on their impact on yield, purity, economics and energy aspects. Aspen Plus® V10 software was used for simulations. Despite meeting international biodiesel standards, significant technical and economic variations exist among the processes. The acid catalytic process exhibits energy requirements surpassing those of alkaline and CaO catalytic processes by over 29.58%, leading to operational costs exceeding those of CaO catalysis by 13.11%. The study establishes CaO catalysis as the most feasible option due to its simplicity, adaptability, and substantial energy and cost reductions. By introducing a closed-loop blending setup configuration, the study reveals that CaO catalysis outperforms alkaline and acid catalysis, achieving 11.59% cost reduction and 13.31% energy decrease in closed-loop configurations. The overall results highlight the potential of non-edible feedstocks in biodiesel production for a more environmentally friendly and sustainable energy future

Sustainable biofuel production in Sub-Saharan Africa: Exploring transesterification process, nonedible feedstocks, and policy implications

This research article was published by Wiley Interdisciplinary Reviews,Volume13, Issue3 2024The world is currently dealing with an energy crisis, primarily due to heavy reliance on finite fossil fuels and the associated rise in energy demand. In response to this crisis, replacing heavy reliance on finite fossil fuels with biodiesel has gained attention as an alternative solution. Sub-Saharan African (SSA) biodiesel studies have traditionally focused on improving transesterification but overlook socio-economic, policy, and institutional impacts on production sustainability. To address this gap, this study comprehensively reviews the sustainability of transesterification-based biodiesel production from nonedible feedstocks in SSA. The study's incorporation of socio-economic factors, policy considerations, sustainability concerns, and institutional frameworks reveals the complex prospects and challenges facing biodiesel production in SSA. The findings reveal that sustainability challenges in SSA stem from a lack of an integrated approach, resulting in conflicting local and global policies. The study determines that neglecting socio-economic factors, policy considerations, sustainability concerns, and institutional frameworks weakens regional biodiesel production sustainability. Evidence from the study emphasizes the role of an integrated approach in promoting biofuel production, establishing markets, and improving the livelihoods of the region's population. Furthermore, the review shows that transesterification can yield biodiesel with comparable physical properties to conventional diesel, making it a wide region's favored option

Thermal Performance and Technoeconomic Analysis of Solar-Assisted Heat Pump Dryer Integrated with Energy Storage Materials for Drying Cavendish Banana (Musa acuminata)

This research article was published by Journal of Food Processing and PreservationThis study examines a novel solar-assisted heat pump dryer integrated with a thermal energy storage system using soapstone as storage material. The dryer is investigated through experimental analysis across three operating modes: mode 1 with thermal energy storage during daytime, mode 2 without thermal energy storage during nighttime, and mode 3 without thermal energy storage during daytime. Experiments were carried out to investigate the drying of 500 g of Cavendish banana. Thermal performance, as well as economic, and nutritional content were examined. Three replicates of the experiment yielded consistent results, showing a significant reduction in the moisture content of the initial sample from 74.4% to 9.6% after undergoing distinct drying durations. Mode 1 achieved this reduction in 270 minutes, mode 2 in 390 minutes, and mode 3 in 360 minutes. The average specific moisture extraction rates for modes 1, 2, and 3 were 0.13, 0.11, and 0.12 kg/kWh, respectively. Simultaneously, the drying rate ranged from 0.16 to 0.24% per minute. The drying efficiency varied among the tested modes, with mode 1 achieving the highest efficiency at 23.23%. In terms of coefficient of performance, mode 1, mode 2, and mode 3 exhibited values of 3.69, 2.57, and 2.54, respectively. The economic analysis conducted specifically for mode 1 revealed a payback period of 1.5 years, indicating the time required to recover the initial investment. Additionally, the results indicated that the dried Cavendish banana had significantly higher concentrations of proximate parameters and minerals compared to the fresh Cavendish banana, as evidenced by a p value less than 0.05

Comprehensive assessment of heat pump dryers for drying agricultural products

This research article was published by Wiley Online Library, 2022Fruits and vegetables are agricultural products that require preservation to enhance and protect shelf life, encapsulate natural flavour, and retain nutritional content. Globally, agricultural products are preserved by a range of means, the most prevalent of which is the heat pump dryer, which produces the best results even in unfavourable climatic conditions. Heat pump dryers come in different types and their performance varies depending on the type. This study aims to evaluate recently developed heat pump dryers based on key performance indicators, impacts on food colour and nutritional content, techno-economic, exergoeconomic, and environmental issues associated with the development of heat pump dryers, which are underrepresented in most of the existing heat pump dryers' reviews. This study also discusses mathematical drying kinetic models, and regulation or policy aspects related to the development of heat pump dryers. In the present study, the results on performance analysis indicate that heat pump dryers examined were effective in reducing drying time and obtaining high coefficients of performance ranging from 1.94 to 5.338 and specific moisture extraction rate ranging from 0.156 to 9.25 kg/kWh, as well as significantly reducing energy consumption by up to 80%. The nutritional composition and colour results show that heat pump dryers maintain the maximum nutrient content while also improving colour. The expansion valve has the lowest exergoeconomic factor of all heat pump dryer components, whereas the compressor has the highest cost of exergy destruction in general, according to the results of exergoeconomic analysis. Techno-economic analysis results demonstrated that most developed heat pump dryers have short payback periods ranging from 1.6 to 3.6 years. However, due to a lack of research in this field, the environmental implications of heat pump dryers are unknown. As per the findings of this study, future research in this field should focus on the design of simple and low-energy heat pump dryers, life cycle, techno-economic, and exergoeconomic assessments

Modelling of Future Energy Demand for Tanzania

This paper present modelling of long-term energy demand forecast in the main economic sectors of Tanzania. The forecast of energy demand for all economic sectors is analyzed by using the Model for Analysis of Energy Demand (MAED) for a study period from 2010-2040. In the study three scenarios namely business as usual (BAU), low economic consumption (LEC) and high economic consumption scenario (HEC)  were formulated to simulate possible future long-term energy demand based on socio-economic and technological development with the base year of 2010. Results from all scenario suggests an increased energy demand in consuming sectors with biomass being a dominant energy form in service and household sectors in a study period. Predicted energy demand is projected to increase at a growth rate of 4.1% and reach 74 MTOE in 2040 under BAU scenario. The growth rates for LEC and HEC are projected at 3.5% and 5.1% reaching 62 MTOE and 91 MTOE in 2040 respectively. Electricity demand increases at a rate of 8.5% to reach 4236 kTOE in 2040 under BAU scenario while electricity demand under LEC and HEC increases to 3693 kTOE and 5534 kTOE in 2040 respectively. Sectrorial predicted demand results under both scenarios determines high demand of biomass for service and household sectors with decreasing demand of biomass in industry sector. Transport sectors predicted energy demand pattern suggests an increased demand in passenger transport than freight transport in both scenarios. Final energy demand per capita in both scenario show an increased trend with lower growth in LEC scenario while there is a decrease in energy intensity throughout study period. Key Words: MAED, energy demand, energy demand forecasting, energy demand modellin

Mathematical modeling and extraction of parameters of solar photovoltaic module based on modified Newton–Raphson method

This research article was published in the Results in Physics Volume 57, 2024This paper presents a numerical method for estimating four physical parameters of a single-diode circuit model based on manufacturer’s datasheet. A system of four non-linear equations are formed based on three key points of PV characteristics. The photocurrent, saturation current, ideality factor and the series resistance are solved iteratively using the proposed method. The suggested method is validated using RTC France solar cell, Chloride CHL285P and Photowatt PWP210 modules and the results are verified with respect to the in-field outdoor measurements. The proposed method shows a good agreement with the experimental data. Lastly, The model chosen is simulated under MATLB environment to assess the effects of external physical weather conditions, that is, temperature and solar irradiance. The advantage of the proposed method with respect of existing numerical techniques is that it converged faster than the widely used Newton method. Modeling of PV cell/module is essential in predicting performance of photovoltaic generators at any operating condition.https://doi.org/10.1016/j.rinp.2024.10736

Modelling energy supply options for electricity generations in Tanzania

The current study applies an energy-system model to explore energy supply options in meeting Tanzania’s electricity demands projection from 2010 to 2040. Three economic scenarios namely; business as usual (BAU), low economic consumption scenario (LEC) and high economic growth scenario (HEC) were developed for modelling purposes. Moreover, the study develops a dry weather scenario to explore how the country’s electricity system would behave under dry weather conditions. The model results suggests: If projected final electricity demand increases as anticipated in BAU, LEC and HEC scenarios, the total installed capacity will expand at 9.05%, 8.46% and 9.8% respectively from the base value of 804.2MW. Correspondingly, the model results depict dominance of hydro, coal, natural gas and geothermal as least-cost energy supply options for electricity generation in all scenarios. The alternative dry weather scenario formulated to study electricity system behaviour under uncertain weather conditions suggested a shift of energy supply option to coal and natural gas (NG) dominance replacing hydro energy. The least cost optimization results further depict an insignificant contribution of renewable energy technologies in terms of solar thermal, wind and solar PV into the total generation shares. With that regard, the renewable energy penetration policy option (REPP), as an alternative scenario suggests the importance of policy options that favour renewable energy technologies inclusion in electricity generation. Sensitivity analysis on the discount rate to approximate the influence of discount rate on the future pattern of electricity generation capacity demonstrated that lower values favour wind and coal fired power plants, while higher values favour the NG technologies. Finally, the modelling results conclude the self-sufficiency of the country in generating future electricity using its own energy resources

Modelling energy supply options for electricity generations in Tanzania

The current study applies an energy-system model to explore energy supply options in meeting Tanzania’s electricity demands projection from 2010 to 2040. Three economic scenarios namely; business as usual (BAU), low economic consumption scenario (LEC) and high economic growth scenario (HEC) were developed for modelling purposes. Moreover, the study develops a dry weather scenario to explore how the country’s electricity system would behave under dry weather conditions. The model results suggests: If projected final electricity demand increases as anticipated in BAU, LEC and HEC scenarios, the total installed capacity will expand at 9.05%, 8.46% and 9.8% respectively from the base value of 804.2MW. Correspondingly, the model results depict dominance of hydro, coal, natural gas and geothermal as least-cost energy supply options for electricity generation in all scenarios. The alternative dry weather scenario formulated to study electricity system behaviour under uncertain weather conditions suggested a shift of energy supply option to coal and natural gas (NG) dominance replacing hydro energy. The least cost optimization results further depict an insignificant contribution of renewable energy technologies in terms of solar thermal, wind and solar PV into the total generation shares. With that regard, the renewable energy penetration policy option (REPP), as an alternative scenario suggests the importance of policy options that favour renewable energy technologies inclusion in electricity generation. Sensitivity analysis on the discount rate to approximate the influence of discount rate on the future pattern of electricity generation capacity demonstrated that lower values favour wind and coal fired power plants, while higher values favour the NG technologies. Finally, the modelling results conclude the self-sufficiency of the country in generating future electricity using its own energy resources

The Status and Future Prospects of Hydropower for Sustainable Water and Energy Development in Tanzania

Tanzania is among the countries with the fastest growing economy in Africa and therefore the need for affordable, clean, and most importantly sustainable electrical energy to meet her ever growing demands is pressing. In recent years, the country’s electricity needs have been largely dominated by thermal generations despite the fact that Tanzania is gifted with huge hydropower resource potential approximated at 38,000 MW with only a very small portion exploited to date. However, the exploited potential is expected to grow by commissioning of identified large and medium-scale hydropower projects with a total installed capacity of 4,765 MW currently under various stages of implementation. Moreover, the geographical location of Tanzania has several benefits to support development of small hydropower projects essential for appropriate utilization of available water resources as a way of mitigating climate challenges effects. Over the last decade, the country electricity demand along with end-use of energy has witnessed significant increases as economic development spreads towards achieving Vision 2025 goals. Proposed hydropower developments are projected to have enormous benefits in the acceleration of economic growth while contributing to greenhouse gas emissions reduction. In this paper, hydropower, which is one of the domestic options for clean energy development path, its present and future potential status, and water resources are explored based on a comprehensive review of energy sector relevant documents and polices