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Although some research on solar energy such as PV, Concentrated Solar Power (CSP), Solar Water Heating (SWH) has been carried out in South Africa, no single study has been carried out that identifies and determines the potential of solar PV using a set of pre-defined critical parameters in different scenarios. Moreover, no study that has investigated the household energy use patterns in different provinces across various income categories. Then, the aim of the project is to identify and assess solar PV using an appropriate set of parameters in each province, employing specific and suitable software to analyse the potential. Moreover, the technical potential for the different types of solar PV technology has not yet been researched in South Africa, taking into consideration the efficiency of the technologies (crystalline and thin film) and degradation rate.

The existing studies in the field of hybrid energy have mainly focused on economic and financial viability using the Hybrid Optimisation Model for Electric Renewables (HOMER) GIS software. One criticism about this literature is that studies are rather insufficient and biased towards the quantification of solar PV potential and the hybrid energy system. Moreover, there is inconsistency in identifying hybrid energy systems; some studies use methods that are inadequate and lack key parameters input that determines the viability of hybrid energy system in different provinces. Moreover, energy consumption pattern at a household level (for different income household) for grid-connected electricity and off-grid solar PV has not been done in South Africa. Thus, this research seeks to obtain answers to these questions.

One criticism of much of the literature regarding the identification of the potential of solar PV and hybrid energy system is that the software used relies almost entirely on solar irradiance data, yet there are other equally important factors and parameters that should be considered in modelling solar PV and hybrid energy system potential. All the studies reviewed so far have, however, suffered from the fact that the software used is unable to provide different scenarios informed by weightings on different parameters to create an enabling environment for informed decision-making. The methods used in previous research are as follows:

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 Potential of concentrated solar power (CSP): Fluri, 2009)

Fluri (2009) measured the potential for CSP using solar radiation data derived from the satellite imagery of the United States National Renewable Energy Laboratory (NREL) and the United States National Aeronautics and Space Administration (NASA) and appropriate GIS software analysis.

The parameters used in this study were:  Proximity to the transmission lines (km);  Solar radiation, available area (km2_);  Land use profile and slope; and  Water availability.

Although this was for CSP and not PV, this method relies heavily on solar radiation and lacks crucial parameters such as electrification backlog, electricity consumption and population, which are key in determining sites that are more suitable for CSP. Moreover, it does not provide more than one scenario as options for decision-making.

 Redrawing the solar map of South Africa for photovoltaic applications:

Munzhedzi and Sebitosi, 2009

This research used the Meteonorm and PVDesignPro software packages to redraw the solar map of South Africa for PV application. The rationale was to map areas and locations where there is good solar PV application (Munzhedzi and Sebitosi, 2009). The following software was used:

Meteonorm: This software takes in a location as a set of coordinates of latitude and longitude and generates climate data for the selected or preferred locations.

PVDesignPro: This is a solar design software package that simulates solar PV system operation on an hourly basis for a year, based on a user-selected climate and system design. The parameters that Meteonorm software considered relevant for the performance of solar PV were generated at hourly intervals for the duration of a year, namely dry-bulb temperature/air temperature, wet-bulb temperature, dew-point

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temperature, wind direction, wind speed, global radiation, diffuse radiation, cloud cover fraction and relative humidity.

All input parameters are entered into the software, the only variable being climate, and the solar fraction is calculated. The fraction gives an indication of the percentage of load that would be supplied by a specified number of panels in a specific location. Hence, maps were generated indicating the solar PV potential in a specific location. Again, this software is good to map solar PV performance for a particular area to give economic and market potential and it further provides sites with good theoretical solar PV potential. However, it omits critical parameters such as land space, which is not modelled, and does not give different scenarios for informed decision-making.

 Economic analysis of PV/diesel hybrid power systems in different climatic

zones of South Africa: Dekker et al., 2012

This research modelled the economic feasibility of a hybrid energy system using climate data (kWh/m2_{/day) to predict certain outputs of the system based in different} geographical locations around South Africa. Moreover, the average/annual load profile of a typical residential house is used to obtain the correct size and type of solar PV modules, charge controller, batteries and converter and the size of the diesel generator to meet the load.

The software used for Dekker at al. (2012) study was the HOMER GIS in different climatic zones of South Africa. The HOMER is crucial for the design of a hybrid renewable energy system in a particular location especially comparison of different simulations around energy yield and economic feasibility, but not for determining potential in a particular location. HOMER GIS is mainly a step forward after determining the renewable energy potential in a particular province. It is then used to design a suitable system that would be economically and financially viable in a particular area.

The technical potential, which usually considers the type of PV technology as well as its efficiency, has not been investigated in South Africa, though Dekker et al. 2012 touched slightly on the PV technology, but did not investigate deeper, as the HOMER software focuses on economic and financial aspects of the solar plant. This study

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modelled solar PV and hybrid potential using the Design Matrix Methods Application software version 1.0 © 2009 by John Dalton ([email protected])1_{. The modelling} was based on the following set of key parameters that have not yet been considered simultaneously in any software: Solar radiation, wind energy, electricity tariff, population, land space, electricity consumption and electrification backlog.

Moreover, these parameters were modelled in different weightings and in three different scenarios. This study sought to achieve the following regarding investigation of the solar PV and hybrid potential in South Africa, which previous research studies failed to resolve:

 Investigating and modelling the solar PV potential in different provinces;

 Investigating and modelling the hybrid energy potential in the three coastal provinces;

 Calculating the technical potential using two types of solar PV technology (thin- film and crystalline modules) and assessing the variation in order to determine the technology impact;

 Investigate different household energy pattern from low, middle and high income categories in different provinces; and

 Determining the monthly variation in solar PV output in respect of different seasons.