(i) High voltage supply
    Max demand in kVA = 312.50 
    Considering losses in hv equipment, the capacity is = 325.52 kVA 
    Annual interest and depreciation = Rs. 1953 
    Annual charge due to max kVA demand = Rs. 17578 
    Units consumed/year = 500000 kWh 
    Annual charge due to kWh consumption = Rs. 25000 
    Total annual cost = Rs. 44531 

(ii)Low voltage supply
    Max demand in kVA = 312.50 
    Annual charge due to max kVA demand = Rs. 18750 
    Units consumed/year = 480000 kWh 
    Annual charge due to kWh consumption = Rs. 26400 
    Total annual cost = Rs. 45150 

Difference in annual costs of two systems = Rs. 619 

