Electrical Engineering, Energy and Physics

Floods have prevailed in the recent years, hampering not only social but also the economic development as well.
This global pandemic has caused loss of lives, property and economic damages in many countries, including
Zimbabwe. Rainfall intensity in the country's seven main river catchments namely; Mzingwane, Gwayi, Save (or
Sabi), Mazowe (or Mazoe), Sanyati, Manyame and Runde triggers flash floods due to high peak discharges. It is
therefore of paramount importance to try and reduce or rather prevent these losses due to flood events. The main
objective of this study is to ascertain flood events in Zimbabwe and discuss how best they can be managed for a
sustainable future. The assessment is carried out using AQUEDUCT Global Flood Analyzer in which all the
analysis is based on the Gross Domestic Product (GDP), population and the present and future (2030) urban
damage. To estimate future changes and effectively suggest flood disaster management and mitigation strategies,
three scenarios obtained from the Intergovernmental Panel on Climate Change 5th Assessment Report were
utilized. A 5-year flood protection was then employed and the urban damage due to the flood events, the
population at risk and the effects of this disaster on GDP was determined. This study outlined that in any given
year, the majority of Zimbabwe has a low to a medium that is 2–3% probability of flood occurrence in which a 5-
year flood has a 20% occurrence probability in any given year. If there is no flood protection employed, this 5-
year flood could cause $106.3 thousand affected population, $32.4 million urban damage and $67.9 million
affected GDP. It is concluded that it is impossible to completely eliminate flood events, however, proposed
mitigation measures, diminution approach and proper planning and preparation before their occurrence can
reduce the environmental, economic and social losses.

— Renewable energy resources such as solar resources are suitable alternatives for the use of fossil fuels as they are abundant, can be harnessed in affordable ways and are considered environmentally friendly. However, renewable energy resources fluctuate with time which decreases the matching between the energy produced by the renewable energy system and the demand and also decreases the reliability of the power supply. There are several potential ways to increase the matching and reliability of the renewable energy systems such as the hybridization of renewable energy resources and the integration of energy storage. A techno-economic analysis of different configurations of Photovoltaic, Hydrogen Fuel Cell (HFC) and Pumped Hydro Storage (PHS) is carried out where Middle East Technical University Northern Cyprus Campus (METU NCC) is the case study. The optimal configurations of the PV system with different energy storage system configurations for the university are found based on maximizing the renewable energy (RES) fraction with Levelized Cost of Electricity (LCOE) equals to the grid tariff. However, the objective of the optimization becomes the maximization of the RES fraction with the minimum LCOE if there is no a feasible configuration. The results show that the integration of HFC and PHS system with the PV system increases the RES fraction and the demand-supply fraction from 36.2% to 45.4% and from 23.9% to 35.1%, respectively. The proposed system consists of 2.57 MW PV, 1.16 MWh HFC and 4.14 MWh PHS where such a system has LCOE of 0.181 USD/kWh.

This present study is aimed at minimizing the dependence on fossil fuels thus reducing greenhouse gas (GHG) emissions and also to curb for the rising energy demands in Kenya. 23 locations are considered for their techno-economic potential of installation of a 10MW grid-connected PV. The sites are scattered across the country yet are mostly concentrated in the Eastern region and are selected based on their accessibility to the power grid and availability of their meteorological parameters from the NASA Solar Energy Dataset. RETScreen software 4.0 version is employed for the analysis. The capacity factor, simple payback, equity payback, the net present value, annual life cycle savings, energy production cost, net annual greenhouse gas emission reduction and the equivalent barrels of crude oil not consumed are outlined. Energy accounting is performed and the results are used to conclude the feasibility of the PV investment.

Fluctuations in fossil fuel prices significantly affect the economies of countries, especially oil-importing countries, hence these countries are thoroughly investigating the increase in the utilization of renewable energy resources as it is abundant and locally available in all the countries despite challenges. Renewable energy systems (RES) such as solar and wind systems offer suitable alternatives for fossil fuels and could ensure the energy security of countries in a feasible way. Zimbabwe is one of the African countries that import a significant portion of its energy needs which endanger the energy security of the country. Several studies in the literature discussed the feasibility of different standalone and hybrid RES either with or without energy storage systems to either maximize the technical feasibility or the economic feasibility; however, none of the studies considered maximizing both feasibilities at the same time. Therefore, we present a techno-economic comparison of ...

Fossil fuel-based energy sources are the major contributors to greenhouse gas (GHG) emission and thus the use of renewable energy (RE) is becoming the best alternative to cater for the increasing energy demand in both developing and developed nations. Chipendeke is a rural community in Zimbabwe, in which electricity demand is partially served by the only micro-hydro plant and hence, load shedding is a regular practice to keep essential services running. This study explored a suitable opportunity to identify a feasible system with different energy sources that can fulfill the current and projected future load demand of the community. A techno-economic feasibility study for a hybrid RE based power system (REPS) is examined considering various energy sources and cost functions. Six different system configurations have been designed with different sizing combinations to identify the most optimum solution for the locality considering techno-economic and environmental viability. The performance metrics considered to evaluate the best suitable model are; Net Present Cost (NPC), Cost of Energy (COE), Renewable Fraction (RF), excess energy and seasonal load variations. In-depth, sensitivity analyses have been performed to investigate the variations of the studied models with a little variation of input variables. Of the studied configurations, an off-grid hybrid Hydro/PV/DG/Battery system was found to be the most economically feasible compared to other configurations. This system had the lowest NPC and COE of $307,657 and $0.165/kWh respectively and the highest RF of 87.5%. The proposed hybrid system could apply to any other remote areas in the region and anywhere worldwide. INDEX TERMS Chipendeke, Zimbabwe, hybrid renewable energy power systems, hydro, solar photovoltaic, battery, diesel generator. I. INTRODUCTION Energy particularly electrical energy is an essential part of modern days living, business and innovation. Access to The associate editor coordinating the review of this manuscript and approving it for publication was Khursheed Aurangzeb. electricity increases the potential to improve living standards, increase opportunity, improve health, productivity and reduces poverty [1]-[3]. It is now considered a basic human right for modern-day living, however, it is not equally experienced by all. More than half a billion people in Sub-Saharan Africa still do not have access to basic electrical energy

Sustainable energy, environmental protection, and global warming are the most discussed topics in today's world. Demand forecasting is paramount for the design of energy generation systems to meet the increasing energy demand. In this chapter, an examination of the causal nexus between energy consumption, total population, greenhouse gas emissions, and per capita GDP was carried out to forecast Zimbabwe's energy consumption by 2030. A time series data from 1980 to 2012 were employed alongside econometric techniques to explore the causal relationship among the variables under review. The stationary test revealed the integration of all the data series of interest of order one ~ I(1). The autoregressive integrated moving average (ARIMA) model forecasted Zimbabwe's 2030 energy demand around 0.183 quadrillion Btu as against the current 0.174 quadrillion Btu. The empirical finding is indicative for policy- and decision makers who design the energy policy framework geared towar...

A situational analysis of future drought and flood impacts in Zimbabwe is outlined in this present study. The assessment under different scenarios is carried out using Aqueduct Global Flood Analyzer in which all the analyses are based on the gross domestic product (GDP), population, and the  present and future (2030) urban damage. In this study, to effectively estimate future changes, three scenarios were employed, namely, IPCC Scenario A2, the Representative Concentration Pathways (RCP) scenario which represents climate change, and the Shared Socio-economic Pathways (SSP) scenario which represents socio-economic change. All these scenarios were employed from the Intergovernmental Panel on Climate Change 5th Assessment Report. To determine current mean monthly precipitation, 1981–2010 data were used and Meteonorm V7 software was employed for the generation of the mean monthly precipitation from 2011 to 2100. The level of flood protection employed is a 10-year one which is used to id...

Historically, minimum system demand has usually occurred overnight. However, in recent years, the increased penetration of rooftop photovoltaic systems (RPVs) has caused an even lower demand at midday, forcing some of the conventional generators to shut down only hours before the evening peak demand period. This further complicates the job of power system operators, who need to run the conventional generator at the minimum stable level at the midday low-demand period so that they can reliably supply power during the peak periods. Employing a community battery storage system can alleviate some of the technical issues caused by the high penetration of RPVs. This paper proposed a design criterion for community battery energy storage systems and employed the battery for the improvement of the duck curve profile and providing the desired level of peak-shaving. Furthermore, remote communities with high penetration of RPVs with a community battery energy storage can achieve the desired lev...

In this present paper, the potential of solar photovoltaic power in Zimbabwe so as to cater for the rising energy demand is assessed. The main objective of this present study is to convert solar resources in 28 different locations scattered all over the country into electrical energy. This investment requires a capital cost of US$18,952,500 and a total land area of 51,020m 2. The 10 MW grid-connected PV potential is feasible for all the chosen locations. Chegutu seems to be the most suitable and profitable site for the construction of the plant and Chiredzi location results in a minimum profit. From an environmental point of view and considering the expected output energy production, investments at Chegutu are highly preferable. The amount of carbon dioxide reduced annually and the cost of electricity are also outlined in this study in which a comparative analysis to the existing grid tariff will be made.

Floods have prevailed in the recent years, hampering not only social but also the economic development as well. This global pandemic has caused loss of lives, property and economic damages in many countries, including Zimbabwe. Rainfall intensity in the country's seven main river catchments namely; Mzingwane, Gwayi, Save (or Sabi), Mazowe (or Mazoe), Sanyati, Manyame and Runde triggers flash floods due to high peak discharges. It is therefore of paramount importance to try and reduce or rather prevent these losses due to flood events. The main objective of this study is to ascertain flood events in Zimbabwe and discuss how best they can be managed for a sustainable future. The assessment is carried out using AQUEDUCT Global Flood Analyzer in which all the analysis is based on the Gross Domestic Product (GDP), population and the present and future (2030) urban damage. To estimate future changes and effectively suggest flood disaster management and mitigation strategies, three scenarios obtained from the Intergovernmental Panel on Climate Change 5th Assessment Report were utilized. A 5-1 Telephone: +905338479557 year flood protection was then employed and the urban damage due to the flood events, the population at risk and the effects of this disaster on GDP was determined. This study outlined that in any given year, the majority of Zimbabwe has a low to a medium that is 2-3% probability of flood occurrence in which a 5-year flood has a 20% occurrence probability in any given year. If there is no flood protection employed, this 5-year flood could cause $106.3 thousand affected population, $32.4 million urban damage and $67.9 million affected GDP. It is concluded that it is impossible to completely eliminate flood events, however, proposed mitigation measures, diminution approach and proper planning and preparation before their occurrence can reduce the environmental, economic and social losses.

The hybridization of renewable energy systems (RES) and further integrating them with Energy Storage Systems (ESS) can help improve the RESs' reliability and reduce the mismatch between energy consumption and generation profiles. The main aim of this study is to suggest a sizing methodology for the RES components with various ESS scenarios in a microgrid through techno-economic feasibility analysis. Although the suggested methodology is flexible to include several RESs and ESSs, the methodology is demonstrated to compare the techno-economic performance of Wind and Photovoltaic (PV) energy systems under four different ESS scenarios; (i) no ESS, (ii) Pumped Hydro Storage (PHS), (iii) Hydrogen Fuel Cell (HFC), and (iv) hybrid ESS (PHS/HFC). The optimal RES configuration is determined by maximizing the RES fraction while equating the Cost of Electricity (COE) to the national utility tariff. However, in the event that there is no feasible system configuration that satisfies the mentioned criteria, the main objective becomes maximizing the RES fraction at the lowest attainable COE. This study outlines that the incorporation of PHS and HFC with the PV/Wind hybrid system increased the demand-supply fraction from 46.5%-89.4% and the RES fraction from 62.6%-91.8% with COE equals to 0.175 USD/kWh.