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Optimized network planning of rural electrification distribution networks using GISEle
Several tools and approaches have been developed and applied to solve rural electrification problems and they are continuously being enhanced to process geospatial information such as population distribution and road access. These data are important for the design of rural electrical networks, hence when neglected may lead to systematical capital investment miscalculations. The proposed strategy employed in this article utilizes the Geographic Information System for Electrification (GISEle) simulation tool that incorporates terrain analysis, cluster analysis and grid routing to create optimum (least-cost) electrical network topologies for the case study of rural and mountainous villages in Lesotho. The GISEle optimized electrical network topology for Makhunoane-1 Community Council consists of four population clusters of 131, 127, 161 and 105 service points, with respective average power demands of 42.348 kW, 41.109 kW, 50.954 kW and 34.86 kW to be supplied by three 50 kVA-rated and one 100 kVA-rated transformers. The projected total cost for the grid extension is €74,303 which is about 38.8% lower than the cost for electrification of the same area as estimated in the national Electrification Master Plan.

2023

  • Thuso S. Motiki
  • Leboli Z. Thamae

Benchmarking of Mini-Grids Regulations for Kenya, Lesotho and Mozambique
This article presents a benchmarking exercise to comparatively analyse the nascent minigrids regulations of Kenya (The Energy (Mini-Grid) Regulations, March 2022), Lesotho (Mini-grid Power Generation, Distribution and Supply Regulations, January 2021) and Mozambique (Regulations on Access to Energy in Off-Grid Areas, December 2021) using a simplified empirical assessment of attributes and elements of regulatory substance to determine their relative potential effectiveness to fulfil their intended objectives. The results indicate that the overall effectiveness and fulfilment rates of the newly developed mini-grids regulations towards attracting and retaining private sector investments and facilitating universal access, have been determined to be 84% for Kenya, 72% for Lesotho and 80% for Mozambique. Nevertheless, the growth of mini-grids will likely remain limited because encroachment by the main grid remains a serious risk to private mini-grid investors in terms of uncertain security of tenure and possibility of stranded assets. The benchmarked regulations appear to offer some promise to mini-grid investors through co-existence, interconnection or asset transfer, but they simply do not provide any solid and assuring process on how to arrive at a fair compensation or purchase price for the mini-grids business in the case of forced exit, except for Kenya which proposes the depreciated value of the mini-grid assets.

2023

  • Leboli Z. Thamae

Meeting electricity demand and generating revenue from production of solar and wind energy
Globally now, electricity is considered as a basic human right. It is imperative that countries seek to increase their national electrification rates and the share of renewable energy in the generation mix in an attempt to achieve universal access by 2030 as stipulated by the UN’s Agenda 2030. In an effort to explore the possibilities of achieving this for Lesotho, the study seeks to model local 60 MW solar PV and 36 MW wind energy plants that could meet the growing national energy demand as envisaged by Independent Power Producers, while also generating revenue by selling excess energy into the Southern African Power Pool. It is observed that the inclusion of solar PV power supply would reduce the 42% monthly average imports supply by 12%, resulting in monthly average imports supply of 30%. The dependence on imports would also be substantially decreased when solar PV is coupled with wind energy, resulting in a monthly average of 75% of the demand being met by local production. Under the current dispatch strategy, on an annual basis, most (95%) of the energy from the solar PV would be consumed locally while 73% of wind generation would be absorbed by the local load while 27% will be available for SAPP export mainly under the preferred Day-Ahead Market.

2021

  • Moruti Kao
  • Sebota Mokeke
  • Matsoso Mothala
  • Leboli Z. Thamae

Simulation and optimization of renewable energy hybrid power system for Semonkong, Lesotho
The vast majority of Lesotho’s landscape is characterized by rugged hills and mountain ranges with sparsely populated rural villages, making it prohibitively expensive and financially unviable to connect these remote villages to the national electricity grid. This lack of access to electricity has hampered many social and economic developments due to insufficient provision of much-needed power to homes, schools, police stations, clinics and local businesses. This paper proposes a renewable energy hybrid power generation system for one such remote town of Semonkong, in Maseru district, Lesotho. The study is based on modelling, simulation and optimization of the hybrid power system using the load profile of Semonkong town and the available renewable resources data of solar radiation, wind speeds and water flow rates from the nearby ‘Maletsunyane River. The HOMER software is used to provide an optimal system configuration in terms of the minimum levelized cost of electricity (LCOE) and the maximum renewable energy fraction, based on various renewable/alternative energy sources of solar photovoltaic, wind turbine, mini-hydro turbine, diesel generator and battery storage. Sensitivity analysis on solar radiation, wind speed, stream flow and diesel price is undertaken to evaluate the feasibility of a completely renewable power system suitable for this remote area application. Simulation results for the isolated optimized hydro/wind/PV/diesel/battery hybrid system configuration achieves LCOE of US$0.234/kW at a renewable energy fraction of 0.95. Thus, the diesel generator will always be required to augment power supply for Semonkong especially during the dry and cold winter months of May to September when the energy demand is at its peak but the solar radiation and stream flow are at their lowest.

2018

  • L.Z. Thamae

 

Review of alternative future approaches to sustainable electricity / energy access for rural communities in Lesotho
The Lesotho government’s commitment to provide clean energy access to predominantly low-income rural communities through electricity grid extension is posing technical and financial challenges to all relevant stakeholders due to remote and hostile terrain, dispersed households, low population densities, over-dependence on subsidies, user affordability and declining revenue collection, among other complications. Policy interventions anchored on universal access fund and fiscal support to facilitate rural access to electricity have achieved an almost 10-fold increase in household customer base from ~25,000 in 2002/03 to ~220,000 in 2016/17. However, during the same period, average annual household electricity consumption has rapidly decreased by about 65% from 3,400 kWh to 1,154 kWh due to newly connected low-consumption households, using electricity mainly for lighting. Another off-grid approach based on stand-alone solar photovoltaic home systems in the country’s three highlands districts suffered a major challenge of social attitude, reliability and ease of use due to lack of local capacity and maintenance programme. This article therefore seeks to review alternative solutions for sustainable future provision of electricity/energy to rural communities in Lesotho based on the outputs of two national studies (electricity cost of service and electrification master plan) undertaken in 2017/18. The former study recommends introduction of lifeline tariff at 5.4 USc/kWh for the first 30 kWh/month for basic electricity needs of the poorest households and the accompanying cross-subsidization mechanism by higher income consumers. The latter study proposes a blended approach of grid extension (with low-cost dual or single-phase rural networks) and off-grid systems (based on stand-alone solar systems, fuel-efficient cook-stoves and hybrid renewable mini/micro-grids). For either approach, households in rural areas will be able to show improved affordability if “electricity market activation support mechanisms” do accompany electrification drives for productive use of electricity in activities generating income for rural communities and creating self-sustained local jobs

2018

Authors Not Mentioned

Modelling electricity sector demand and supply options in Lesotho
Provision of sustainable, reliable, affordable, and possibly clean energy is the primary aim of many developing countries such as Lesotho, which is endowed with renewable energy resources in the form of hydro, solar and wind. With the electricity demand in the country having an average annual growth of 5% while the local hydro generation has remained stagnant at 72 MW since 1998, sound planning and decisive strategies have to be implemented now to mitigate the growing peak demand deficit (currently at 50%) and ensure the right energy mix for future use. In order to formulate and support national energy strategies based on the recently adopted Lesotho Energy Policy 2015 – 2025 and to achieve its goal of ensuring security of supply, medium and long-term electricity demand and supply options forecasting studies are necessary. This article will address this electricity capacity expansion planning gap in Lesotho by providing quantitative analysis and cost-and-benefit trade-offs of different supply options based on operability constraints. Emphasis will be placed on local generation development based on renewable energy technologies (solar, wind, small-hydro) versus continued electricity imports from the Southern African region, using MAED and MESSAGE modelling tools. MAED will be used to model electricity demand while MESSAGE will be used for modelling supply options for the years 2016 – 2030.

2016

  • M. Senatla

Design, Construction and Testing of a Low-Cost Flat Plate Solar Energy Collector

2016

  • A. Tsiu

Optimal Sizing, Performance Prediction and Economic Analysis of Solar Hot Water Systems for Three Hotels in Zimbabwe

2016

  • Rashayi E
  • Madiye L
  • Schwarzlmueller A

Sustainable Energy Curriculum Development under the SASEI project at the National University of Lesotho

2015

Authors Not Mentioned

Analysis and optimisation of a solar powered forced-convection crop dryer

2005

  • Manyumbu E

Demand Side Generation Solar Farm at Moshoeshoe I International Airport
The solar photovoltaic farm is comprised of 1196 polycrystalline modules capable of peak generation of 281,060 Wp. The annual production of the farm in the 2014/15 financial year (April 2014 to March 2015) was 461 MWh, enough to power 220 households in Lesotho. Over 130 MWh of this energy was fed into the grid free of charge, generating over ZAR 130,000 ($1 ≈ ZAR 12) for the utility company by supplying it to the neighbouring households. Using net metering, the airport stands a chance to reduce its electricity bill by 47%, almost half. Normalised values are utilised for the performance parameters so that it would be easy to compare with other farms. The average monthly array, inverter and system efficiencies are 12%, 89% and 10%, respectively. These are ideal for grid-connected photovoltaic systems. The annual final yield is 1,640 kWh/kWp which is higher than a lot of solar power generating leading countries. The average performance ratio is 0.72 which is slightly below the global optimal value of 0.74. Lesotho uses over ZAR 200 million/annum to import 40% of its energy consumption. With the optimal technical parameters observed at the farm this money would be well spend on local independent power producers and demand side generating plants. These plants shift the financial risk of development, financing, ownership and operation away from the utility company. ZAR 200m would secure over 250 GWh of solar PV electricity locally which is about as much as is imported from South Africa and around 80% of the total imports

1992

  • Lebohang Mohasoa
  • Molebatsi Monese