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clarkejr
Oct 1, 2010, 08:53 AM
Hello - I am trying to select a pump to pump water from a 1000 litre IBC to another IBC container situated 100 feet away and 3 metres higher - as this pump is going to be powered by a 12v battery and solar powered the pump needs to run as efficiently as possible. I am unsure whether it is better to use a low powered pump with sufficient pressure to overcome losses in the system (horizontal pipe runs plus head hight) and run it slowly over a longer period or a high powered pump over a shorter period. I have been using a hazen-williams type calculator to calculate horizontal pumping pressure losses through the pipes and it seems that the faster the pump runs the greater the pressure resistance which increases the overall pump size required. Any help appreciated with understanding this... thanks John

jlisenbe
Oct 1, 2010, 09:38 AM
The 3 meters of height will cost you 5# or so of pressure. Assuming you will be using 1" pipe, I don't think the 100' run of pipe is even worth worrying about.

clarkejr
Oct 2, 2010, 07:17 AM
jlisenbe - thanks for your swift reply what does 5# mean thanks.

clarkejr
Oct 5, 2010, 03:18 AM
jlisenbe - thanks for your swift reply what does 5# mean thanks.

jlisenbe
Oct 5, 2010, 05:49 AM
5 pounds per square inch of pressure. You lose about 0.4# per foot of elevation, and 3 meters is about 10 feet, so it would really be more like 4 pounds, now that I think about it a second time. In other words, not enough to be concerned about.