## 2 Materials and Methods
### Feasibility Study
The Payback Tool summarizes the results of the financial feasibility in tabular and graphical format for Internal Rate of Return (IRR) and Net Present Value (NPV) over 25 years, accumulated cash flow after 25 years, system life cycle costs for 25 years, years of payback, yearly loan repayment (if applicable) and yearly CO\({}_{2}\) emissions of the three systems. The Finance Deployment Tool is a spreadsheet questionnaire used to identify possible financial mechanisms (products and services) that could be used for the operation and maintenance of MUS. Depending on the Yes/No answer to the questionnaire, the tool excludes/retains potential financial products and services. The questionnaire was compiled based on information obtained during the stakeholder engagement and knowledge of the area. The Pump Sizing Tool was used to configure and design solar-powered groundwater pumping systems for the nine case study sites, namely the required hydraulic lift, power and pump type, the required peak power and the solar panel surface area. Required hydraulic head was calculated based on measurements of groundwater depth and the required hydraulic lift to storage reservoirs. Water quality fitness for a specific use is a pre-requisite for the success of the MUS system. Groundwater samples were therefore collected from water sources at all case study sites and analyzed in the laboratory for chemical and physical properties according to standard procedures (in May 2022 at the end of the rainy season and November 2022 at the end of the dry season). Water quality fitness for irrigation on small-holder farms was assessed by comparison with the South African Water Quality Guidelines for agricultural use [61]. Water quality fitness for drinking purposes was evaluated by comparison with the South African National Standard for drinking water SANS 241: 2015. The water quality evaluation also served to identify the need for water purification or filtering systems. \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline
**Village** & **Site** & **Water Use** & **Borchelo** & **Water requirements** & **Total Dynamic** & **Pipeline Length (m)** & **Pipeline Dinner** & **Peak Power** & **Solar Panel Surface (m\({}^{2}\))** \\ \hline Mibedle & Population = 1220 & Domestic, livestock & 80-90 & 308.8 1 & 33 & 1000 & 60 & 1.5–1.7 & 10.0–11.3 \\ Mayephu & Population = 1940 & Domestic, livestock & 80-90 & 485.1 & 30 & 50 & 60 & 2.2–2.7 & 14.3–18.0 \\ Mizela & Population = 1150 & Domestic, livestock & 80-90 & 28.8 1 & 29 & 50 & 60 & 1.2–1.3 & 8.0–8.7 \\ Matsuoseda & Population = 2300 & Domestic, livestock & 80-90 & 57.5 1 & 30 & 50 & 60 & 2.8–3.4 & 18.7–22.3 \\ Dzuneri & Nhamelto Primary & Domestic, Agriculture & 4 & 58.9 2 & 20 & 300 & 60 & 1.7–2.0 & 11.0–13.0 \\ Dzuneri & Agriculture & Agriculture & 66 & 33.9 & 35 & 150 & 40 & 1.7–2.0 & 11.3–13.3 \\ Dzuneri & Agriculture & Agriculture & 120 & 33.9 & 43 & 300 & 40 & 2.1–2.6 & 14.0–17.3 \\ ([PERSON]) & Agricultural Cooperative & & & & & & & & \\ Lokola & Davadzi Youth Organic & Agriculture & 120 & 33.9 & 35 & 150 & 40 & 1.7–2.0 & 11.3–13.3 \\ Agricultural Cooperative & Agriculture & 40 & 33.9 & 40 & 250 & 40 & 2.0–2.5 & 13.0–16.7 \\ \hline \hline \end{tabular} \({}^{1}\) Calculated as population \(\times\) 25 I / persons/d. \({}^{2}\) Calculated as firm water requirement + requirement of 1000 people (fraction of population of Dinner).  
\end{table} 
Table 1: Case study sites, their water use, water requirements, total dynamic head, pipeline length and diameter, power supply required (peak kW) and solar panel surface area estimated for each proposed pilot site with the Pump Sizing Tool [50].