3.2.2. Cost and Returns on Investment

The initial capital cost for the complete drying system is presented in Table 3. The main cost component, as shown in Table 3, is the fan cost, estimated to be 46.9% of the total investment cost.



The costs associated with the operation and maintenance of the dryer are presented in Table 4. An amount of \$12 representing 2% of the total investment cost is allocated for maintenance and overhead expenses. With a fan of a motor rating of 0.75 kW, a total power of 540 kWh required per an operation cycle, an amount of \$82 is estimated as the cost of electricity for the operation of the drying system. The cost of electricity was estimated at \$0.15 per kWh in Ghana [26].


**Table 4.** Operation and maintenance cost of running the drying system.

At a projected six days of operation per week for the three-month operational period per year, it is expected that the column dryer will be used to dry 72,000 kg of maize per year. At a drying price of \$0.94 charged per bag (130 kg) of maize to be dried, total revenue of \$523 is anticipated since 554 bags of maize will be dried during the operation cycle of three months in a 12-month year.
