Water treatment per year

running time 10 hours a day
= 365 days x 10 = 3650 hours per year

delivery rate per hour at least 900 liters
= per day x 10 hours = 9000 liters per day x 365 days

= 3.285.000 liters per year

Operating cost calculations

Operating costs with existing power source (PDF)
Operating costs with emergency generator (PDF)