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energy efficient water pumps
http://byap.backyardmagazines.com/forum/viewtopic.php?f=8&t=1328		 Page 1 of 3
Author:  aquamad [ Mar 13th, '07, 20:34 ]
Post subject:  energy efficient water pumps
Okay...
After noticing that my bigger submersable water pump heated my water in the IBC by a number of degrees in one day I know (with the help of Steve) that a lt of the energy (electricity) is being lost in the form of heat :(
What I am after are energy efficient water pumps and ways for ordinary people to be able to recognise a pump which is energy efficient (or at least how efficient it could be)

So to start with, do I have these right :?:
# Higher amps means more money down the drain,
# Lower amps means saving more money.
Author:  aquamad [ Mar 13th, '07, 20:36 ]
Post subject: 
I was also given this bit of info...
If you only know the wattage of your pump, divide the watts by the 115 voltage to get the amps, i.e., if your pump has 1,150 watts, then 1,150/115 = 10 amps.

Is this right (steve? )
Author:  steve [ Mar 13th, '07, 20:41 ]
Post subject: 
Quote:
# Higher amps means more money down the drain,
# Lower amps means saving more money.


Yes and no

Yes in the sense that more amps = more Kw = more running cost

No in the sense that you have to compare pumping volumes and pressures

No in the sense that you have to compare electrical power in VS mechanical power out. S&A's for example is 2.1A at 240V (approx) gives 500W

Placard states motor power at .3Kw which is 300W

300/500*100 = 60% efficiency

I'm no mechanical or electrical engineer, so i'm happy to be corrected by someone who knows better ;)
Author:  aquamad [ Mar 13th, '07, 20:45 ]
Post subject: 
:shock:
uuuhhhhhhh :?

I need to read that again - this is stuff I have not gone into a great deal... Who else can put their 5c worth in here.

I just want to be able to work out if the pumps I use are giving me the best value for money :oops:
Author:  RupertofOZ [ Mar 13th, '07, 20:56 ]
Post subject: 
So lets see if I've got this right...

My pump placard says 5.4A at 12V and 50W

so ... 5.4 x 12 =64.8...

50/64.8*100=77.1

77.1% efficient....

That right Steve???

or are things different for 12V??
Author:  aquamad [ Mar 13th, '07, 21:01 ]
Post subject: 
I am going to have to pull up my pumps and jot down their details now to work all this out :?
But I just gotta know - after watching "the story of food", followed by "an inconvinient truth' - I feel I have to do stuff like this :)
Author:  earthbound [ Mar 13th, '07, 21:20 ]
Post subject: 
One issue I have with pump selection, is wanting a pump that is fairly low power, but will suck up the chunks and dump them into my growbeds. It seems like if you want to suck up your solids then your looking at pumps that are over 100W, which sux..... :?
Author:  RupertofOZ [ Mar 13th, '07, 21:33 ]
Post subject: 
Hummm ... so you're saying EB that the ability to suck up the solids is more related to the pump wattage power than to the pumps ability to move water.....

I kinda thought (suse my lack of pump knowledge) that a high(er) volume pump would most likely suck up the solids????
Author:  janethesselberth [ Mar 13th, '07, 21:42 ]
Post subject:  Re: energy efficient water pumps
To me, efficiency is about how many watts I draw to move the water I need moved. So if I need to move 1000gph, and one pump will do it with 100watts, and another will do it with 150 watts, then I should choose the first one. All other things being equal, of course.

Of course, I just re-did my pumping solution because I tried to get away with a trio of pumps that were just too small. That wasn't very efficient in the long run, but seemed it in the short run. Oh well!

I'm now running one pump at 1500gph and 138 watts (10.8gph/watt) instead of 3 pumps at 190gph and 19watts (10gph/watt). I might have been able to get away with a 1100gph pump and 106watts (10.4gph/watt), but I actually think that would have been cutting it a little close.
Author:  earthbound [ Mar 13th, '07, 22:11 ]
Post subject: 
The ability to suck up solids is related to the size of the intake holes in the pump, and generally the smaller the pump (size, wattage, capacity) the smaller the holes..

I wonder whether the pumping capacity varies much with head height..? That is, are there different pumps but with the same wattage and flow rate, and yet one might be more efficient when pumping to a certain head..?

One factor that can be even more important than the pumps efficiency, is reliability.
Author:  aquamad [ Mar 13th, '07, 22:16 ]
Post subject: 
Quote:
One factor that can be even more important than the pumps efficiency, is reliability

That is a big one!
2 of the smaller ones I bought last year to runn my bath tub system have already packed up (grrrr) :( so that is abot $50 to $60 down the tubes!... wher as my old above ground pool pump is still going strong and I bought that for $25 (plus a box of pipes and assorted fittings to boot )
reliability is a definate factor (there is so much to balance out! :shock: )
Author:  Daniel [ Mar 13th, '07, 22:25 ]
Post subject: 
aquamad wrote:
Quote:
One factor that can be even more important than the pumps efficiency, is reliability

That is a big one!
2 of the smaller ones I bought last year to runn my bath tub system have already packed up (grrrr) :( so that is abot $50 to $60 down the tubes!... wher as my old above ground pool pump is still going strong and I bought that for $25 (plus a box of pipes and assorted fittings to boot )
reliability is a definate factor (there is so much to balance out! :shock: )

yeah, i had an impellor break on my pump, but managed to fix it (with sillicone) and been running for a month now.......

however, i am going to get a backup one for when it breaks again, has anyone found a efficient and reliable pump anywhere in aus?
Author:  aquamad [ Mar 13th, '07, 22:31 ]
Post subject: 
yeah, at the LifeLine buy back shop ;)
Author:  TimC [ Mar 13th, '07, 22:51 ]
Post subject: 
Plus, going on the different pump styles, the normal 5 bladed straight impeller is prone to blockages, where as some of the larger pumps have a different impeller.

As for reliable and efficient pumps, I have two eheim submersibles which were bought when I was too young to remember. They have been used in 4 different ponds and most of my projects.... Still going strong. My Jebao 4,500LPH pump has been doing great so far too.
Author:  monya [ Mar 14th, '07, 04:18 ]
Post subject: 
I think the solids issue si best addressed by using a MF/VB style centre drain on syphon with one pump in the sump.
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