Users Guide to off Grid Energy Solutions

What is Head & Lift Fact Sheet:

Vertical Lift: The vertical distance that water is pumped. This determines the pressure that the pump pushes against. Total vertical lift = vertical lift from surface of water source up to the discharge in the tank + (in a pressure system) discharge pressure. Synonym: static head.

Head (synonym for vertical lift) and total dynamic head: Total Dynamic Head is equal to vertical lift plus friction loss in piping. In water distribution terms (e.g., for hydropower design) the synonym for head is vertical drop.

Note: Horizontal distance does NOT add to the vertical lift, except in terms of pipe friction loss. NOR does the volume (weight) of water contained in pipe or tank. Submergence of the pump does NOT add to the vertical lift.

Friction Loss: The loss of pressure due to flow of water in pipe. This is determined by 3 factors - pipe size (inside diameter), flow rate, and length of pipe. It is determined by consulting a friction loss chart available in an engineering reference book or from a pipe supplier. It is expressed in PSI (pounds per square inch) or bar (1 bar equals 1 kilogram per square centimetre), or feet or metres (equivalent additional feet or metres of pumping).

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