A refrigeration system for storing vaccines in a remote African village uses $2$kWh per day and must operate $24$ hours a day over its expected lifetime of $20$ years. A stand$-$alone power system must be designed to power this vital equipment. Two systems are under consideration: A PV system comprising a $500$ W PV array, costing $3$ per watt, storage batteries costing $1250$ and must be replaced every $5$ years, and a charge controller that costs $450.$ The maintenance cost for the system is $250$ annually. The alternative is a $500$ W diesel generator that costs $450.$ It has an annual fuel requirement that costs $400$ and it costs $80$ annually for oil changes and servicing. This generator would need replacing every $$ve years. If the in$$ation rate is assumed to be $2\%$ and the discount rate is $8\%,$ perform a life$-$cycle cost analysis to determine which system should be used.