To calculate the power consumption of your water pump just put the wattage of your water pump, operational hours and electricity tariff of your locality and you will get the units of electricity consumed by your water pump and the impact it has on your electricity bill.
You can find your water pump rated wattage on the specification plate which is normally pasted on the pump.
If you can’t find the rated power of your water pump over there, then just find a similar type water pump on amazon and check its wattage in the description or go to your water pump manufacturer website and there you can find the wattage.
To give you a rough estimate the average rated power of water pump is from 250 watts to 1500 watts. Smaller the water pump, less is the wattage, less is the power consumption, hence low is the discharge and head.
If the rated power is given in horse power (hp) then convert it to watt by multiplying it with 746. (1 hp = 746 watt).