2025-11-29
Ashleen Marshall, DI O Ikhu-Omoregbe
South Africa is faced with persistent energy shortages and the need to develop sustainable, renewable resources. This research aimed to produce biomethane (biogas) via anaerobic digestion using a synthetic inoculum and the brown seaweed Ecklonia maxima . The biogas can be utilised in a simple combined heat and power process and converted to electricity and heat. Biogas production is estimated using the biomethane potential utilising the chemical composition of the seaweed. This is then compared to the actual biogas production from the anaerobic reaction of the seaweed and the inoculum at both mesophilic and thermophilic conditions. The research found that seaweed yielded 190.00 ml/g volatile solids (VS) of biogas after 28 days at a pH of 7.0 ±0.2 at mesophilic conditions, which is equivalent to 38% of the calculated biomethane potential of 499.64 ml/g VS. Ecklonia maxima can produce 255.18 kg biogas per ton of dry seaweed, with a possible associated 1417.71 kWh of electricity per ton of dry seaweed. Future work would investigate pre-treatment options for the seaweed to increase the biogas yield and increase the potential electricity output per ton of dry seaweed.
2025-08-07
Madhusudhanan Sampath, Amalorpava Mary Rajee Samuel, Yamuna Devi M.M, Senthil Murugan
Greenhouse gases (GHGs) are the main cause of global warming. Reducing emissions would contribute to environmental sustainability and could also have economic advantages. GHGs can be reduced by using the hybrid energy system (HES). In developing countries, analysing energy transitions and unmet energy needs should focus on identifying strategies for transitioning to more sustainable energy systems while ensuring access for all. This study looks at the mitigation of GHG emissions by using clean HES energy with battery optimisation. The paper presents an improved Lyapunov optimisation (LO) algorithm to optimally estimate the number of photovoltaic panels and battery banks for enhanced energy management. To increase system efficiency, the losses of power and over-production and under-utilised energy have been considered. The stability analysis is evaluated using the LO algorithm, specifically focusing on the changes predicted by the energy index of the self-reliance report, optimising the system’s performance under varying environmental conditions.
2025-05-10
Chantelle Clohessy, Warren Brettenny, Waldo Abrahams
Ground-based solar resource measurements are known to be preferred to synthetic or simulated data for a given location, but outliers present in this data can significantly impact the accuracy of predictions used in viability assessments. For solar energy installations to be self-sustaining and viable, accurate ground-based solar resource data for the location of these installations are essential for decision-making and planning. Conventional outlier detection techniques used for solar resources, including graphical plots to complex numerical approaches, often have difficulty identifying these outliers to a satisfactory degree. This study proposes the use of simulated outliers added to synthetic data to train and compare the effectiveness of traditional outlier detection methods and several statistical learning methods, including NN, naïve Bayes, support vector machines and advanced tree-based models for the purpose of outlier detection in this field. The results indicate that the advanced tree-based models provide accurate identification of outliers in the simulation step and are demonstrated to be effective on a ground-based real world data set collected in Gqeberha, South Africa. The use of the proposed approach can aid in reducing the uncertainty in measured solar resource data and, as a result, help to promote the use of solar energy solutions in areas with unreliable solar resource data.
2025-05-01
Hope Baxter Chamdimba, Emmanuel Mtanila Banda
The hotel sector is a vital component of the tourism industry, as it plays a critical role in the determination of tourism destination competitiveness. However, lack of reliable, affordable, and sustainable energy supply remains a major bottleneck to the development of the hotel sector in Malawi. The adoption of clean and renewable energy sources around the globe is driven by different factors, such as the need to address environmental challenges and reduce energy costs. Usually, less affordable energy supplies increase the cost of service delivery, thus making these hotels less competitive on the global market. The article investigates the opportunities and barriers to the hotel industry's adoption of renewable energy technologies and includes a literature review. The paper shows that renewable energy technologies have multiple applications in a typical Malawian hotel, and these present numerous economic and environmental opportunities. However, the hotel sector is failing to capitalise on the energy policy and regulation improvements taking place in the country, mainly due to a lack of technological awareness by hotel managers. To reverse this, the government needs to adopt policies and regulations that target the hotel sector to increase awareness and adoption of clean and renewable energy technologies.
2024-10-04
Oliver Dzobo, Lucas Tivani, Lindani Mbatha
Distributed energy resources (DERs), including solar panels, wind turbines, and battery storage, are becoming more prevalent in power grids. This increased penetration necessitates a closer look at how they impact the grid's operation. Power grid operators face challenges in ensuring the secure operation of the network in the presence of DERs. This includes managing voltage fluctuations, integrating diverse energy sources, and preventing grid overloads. This paper reviews the impacts of DERs on power grid operation and discusses strategies for enhancing the integration of DERs in South Africa’s grid. The strategies involve technology solutions, grid management techniques, and policy changes that facilitate the seamless integration of renewable energy sources. Smart inverters are highlighted as an essential component of the solution. Their advanced capabilities play a central role in managing voltage, frequency, and other aspects of power quality, which is critical when integrating DERs. The paper offers a comprehensive overview of the challenges of integrating inverter-based DERs into the power grid, highlighting lacks and deficiencies in existing South Africa power grid codes and standards and discussing solutions – thus paving a way for future investigations and developments. Eight international regulations are examined and compared, exposing the lack of a worldwide harmonisation and a consistent communication protocol. The paper calls for the evolution of power grid codes to adapt to the changing energy landscape and to harness the benefits of DERs and advanced smart inverter capabilities. This involves updating regulations and standards to ensure grid stability and reliability while accommodating renewable energy sources. The review can aid power utilities and regulators in making informed decisions in enhancing grid-connected DERs and ensuring safe and secure grid operation.
2024-08-29
Momina Malik, Mark Gilpin, Bruce Graham
Abstract There is a global need for clean and renewable energy sources. This study investigated thermoelectric generators (TEGs) as a possible method for harvesting solar power. The TEG prototype tested here consisted of two equally sized pieces of roof sheeting, with one side exposed to a light source and the other side shaded. Experiments were carried out with the necessary testing components to investigate the effects that two variables have on the amount of power generated: first, the colour of metal inverted box rib (IBR) sheeting and, second, the ideal electrical arrangement for scalability of Peltier tiles for maximum power output. Black-coated sheets generated maximum power ( Pmax) output of the TEGs. The TEGs in series configuration generated the highest Pmax when located closest to the light source. The conclusion from the experiment is that TEGs are a potential method of harvesting solar energy on IBR sheeting, specifically in a vertical position. However, applications of different orientations and geographical locations require further investigation, including into the use of TEGs on IBR sheeting for harvesting solar energy on a larger scale.
2022-09-26
Richard Cartland, Al-Mas Sendegeya, Jean de Dieu Khan Hakizimana
The provision of electricity in rural areas has been an outstanding need in trying to achieve the United Nations sustainable development goals (SDGs) by 2030. However, most sub-Saharan countries have found this difficult due to financial constraints. Uganda tried to increase rural electrification to more than 20% of its population by 2020 through Rural Electrification Agency programmes. In an attempt to realise SDGs and the National Vision by 2040, Uganda is investing more in renewable energy sources, especially solar photovoltaic mini-grids to ensure that rural areas access affordable, reliable, and sustainable modern energy. This paper assesses the operation, causes of failure, causes of discomfort for mini-grid connected customers, and customer behavior of two solar photovoltaic mini-grids located in Kyenjojo District in western Uganda. It was found that the current energy demand exceeds the generation supply and that the systems need phase upgrades and clustering to remain economically viable and sustainable. The methodology involved re-sizing the existing load demand of the connected users, well-designed and administered questionnaires, analysis of published literature, review of the existing records, and interviews. Analysis was done in an Excel software program. The paper concludes by identifying the benefits and challenges of solar photovoltaic mini-grids in Kyenjojo District.
2022-06-17
Matsoso Mothala, Retselisitsoe Thamae, Moeketsi Mpholo
The determinants of household energy fuel choice have not been studied in some developing countries, including Lesotho, despite the potential benefits such a study might have for policy design and implementation. This study uses the data collected by Lesotho’s Bureau of Statistics through a national household energy consumption survey of 2017, and a multinomial logistic regression to analyse the determinants of household energy fuel choice in Lesotho. The results indicate that the gender of the household head does not influence the choice of cleaner energy fuels for cooking and water heating. However, the age and education of the household head, household size, level of income, and access to electricity are drivers of energy fuel choice. The older the household head and the larger the household, the less likely it is to adopt cleaner energy fuels. Generally, higher income, access to electricity and a better-educated household head make a household more likely to adopt clean energy fuels. Thus, policies aimed at promoting household income-generating opportunities, effective provision of access to electricity, and investment in education can influence the choice of clean energy use within households. But these policies must be tailored to the unique characteristics of different settlement types, given that the significance of these determinants vary across rural, peri-urban, and urban areas.
2021-12-13
Farzad Ghayoor, Andrew Swanson, Hudson Sibanda
Many countries, including South Africa, have introduced policies and incentives to increase their renewable energy capacities in order to address environmental concerns and reduce pollutant emissions into the atmosphere. In addition, consumers in South Africa have faced the ever-increasing price of electricity and unreliability of the grid since 2007 due to the lack of sufficient electricity production. As a result, employing hybrid renewable energy systems (HRESs) have gained popularity. This research focuses on grid-connected HRESs based on solar photovoltaic (PV) panels and wind turbines as a potential way of reducing the dependency of residential sector consumers on the grid. It aims to identify the optimal sizing of renewable energy sources to be cost-effective for consumers over a certain period of time, using Durban as a case study. Two artificial intelligence methods have been used to obtain the optimal sizing for the available PV panels, wind turbines and inverters. The results shown that the combination of PV panels and battery storage can be a profitable option. A system using higher rated power PV panels can start to become profitable in a shorter lifetime, but employing batteries can only be cost-effective if a long enough lifetime is considered.
2021-12-13
I. Lemba, M. Ferreira Dias, M. Robaina
The socioeconomic development of any region requires electricity for operating the various sectors of the economy. Sometimes energy is scarce, not only because of the lack of energy resources, but also because energy policy is inadequate or non-existent. This paper examines the situation in the province of Namibe, Angola, characterising the energy sector, and proposing an energy mix for the security of electricity supply, environmental protection and sustainable economic development. Using the Long-range Energy Alternative and Planning System, energy scenarios were simulated and the greenhouse gas emissions (GHGs) for the period 2014-2040 calculated and analysed. The most sustainable scenario, in terms of energy mix diversification and GHG reduction, as well as the least costly (considering electricity production and carbon costs), has an increase of hydro capacity and the insertion of wind, solar photovoltaic, thermoelectric sources and natural gas. Given the intermittency of photovoltaic and wind systems, natural gas appears in this scenario as a way to avoid interruptions in the electricity supply. This scenario is the one with the largest production reserve margin of 24.47 %, and emissions are avoided at 386 550 tCO 2 eq compared to the base scenario in 2040. Energy policymakers can take this scenario as a model to assist in making decisions on how power capacities can be installed over the planned time for the desired energy output.
2018-06-22
Thapelo Cornelius Mosetlhe, Adedayo Ademola Yusuff, Yskandar Hamam
Global warming and the energy crisis have necessitated an urgent exploitation and utilisation of renewable energy. Wind energy has gained popularity over the years because of vast availability of its resource. A study was carried out to investigate the stochastic characteristics of the available wind energy at installation sites. Data for a ten-minute interval wind speed collected over a period of five years and measured at a height of 10, 40 and 62 m in Vredendal was considered. Wind speed data was arranged in seasonal format and its statistical distribution investigated based on Weibull, lognormal and gamma distributions. The Anderson-Darling test and Akaike information criterion were used to evaluate the goodness of fit. The results showed that wind power at different heights and time stamps exhibited different statistical distribution. It was found that wind turbines in Vredendal must be installed as high as possible to harness wind power effectively. During summer and spring, there was a high potential for wind power availability compared with that of winter.
2017-06-23
Tafadzwa Makonese, Daniel M. Masekameni, Harold J. Annegarn
Informal fixed-bed coal-burning braziers are used extensively in low-income communities of South Africa for space-heating and cooking needs. An investigation was carried out on the effects of coal moisture content and coal quality on the thermal and emissions performance of domestic coal-burning braziers in three field-procured braziers (with three different air ventilation rates), using the bottom-lit updraft (BLUD) and top-lit updraft (TLUD) ignition methods. Results showed that an increase in coal moisture content (from 2.4 wt.% to 8.6 wt.%) led to 18% and 30% decreases in fire-power when using the TLUD and BLUD methods, respectively. The combustion efficiency increased by 25% with an increase in moisture content. Measured carbon monoxide (CO) emission factors increased with an increase in moisture content, while carbon dioxide (CO2) emission factors remained unchanged. The use of A-grade coal resulted in a 49% increase in PM emissions compared with D-grade coal at high ventilation rates, despite no statistically significant differences (p > 0.05) in CO and CO2 emission factors produced between coal grades.
2016-09-23
Gerro Johannes Prinsloo, Robert Dobson, Alan Brent
For many off-grid rural communities, renewable energy resources may be the only viable option for household and village energy supply and electrification. This is especially true for many rural regions in Southern Africa, where the population spread is characterised by small villages. These rural villages rely heavily on firewood and biomass to meet thermal energy needs (hot water and cooking), while candles, kerosene and paraffin are mostly used for lighting. Hybrid concentrated solar micro-CHP (combined heat and power) technology systems have been proposed as viable energy solutions. This paper conducts a scoping exercise to determine realistic hourly reference profile shapes for thermal and power energy consumption in isolated rural African villages. The results offer realistic energy consumption load profiles for a typical rural African village in time-series format. These reference load profiles enable experimental comparison between computer modelled solar micro-CHP systems and control automation solutions in isolated rural village micro-grid simulations.
2006-11-01
K Gratwick, R Ghanadan, A Eberhard
Initially conceived of within the broader context of power sector reform in the late 1980s and early 1990s, Independent Power Projects (IPPs) were intended to relieve state utilities of the burden of financing new plants, bring quick, quality power and reduce costs for end-users. Although IPPs have indeed contributed to generation capacity in Tanzania, much of the power that resulted from investments has been supplied neither quickly nor cheaply. Embarking on power sector reform in the early 1990s, Tanzania made IPPs a pillar of its reform strategy. Presently, Songas and IPTL, the country’s two IPPs are helping to reduce load shedding. However, these projects have not been without controversy. One of Tanzania’s IPPs was taken to international arbitration over a dispute related to construction costs. The state electric utility, Tanzania Electric Supply Company Limited (TANESCO), currently pays more than 50% of its current revenue towards combined fuel and capacity charges for the IPPs. Capacity charges for the country’s two IPPs are equivalent to approximately one percent of GDP. The Government of Tanzania (GoT) is intervening to assist TANESCO with its monthly IPP payments at present. With twenty-year Power Purchase Agreements (PPAs) between IPPs and TANESCO, these costs are expected to continue, albeit with some modifications due to refinancing, fuel conversion and further development of the natural gas market. This paper provides a detailed summary of how and why IPPs developed in Tanzania as well as their impact to date. Development outcomes, namely the extent to which the host country is benefiting from reliable, affordable power and investment outcomes, the degree to which investors have made favourable returns and been able to expand market share, are analysed in turn. IPPs offer more than a decade of experiences in private sector investment in developing countries and a detailed understanding of them may be the key to unlocking and sustaining future power investment.