Hi Mark

this was most helpful (I am a SW engineer so I lenjoy this kind of thing ) it is now MUCH clearer how thie pieces fit together.

The Intelliflo curves can be found at pg 47 of

http://www.pentairpool.com/misc/owne...User_Guide.pdf

So if today I have 40 ft of head at 40 GPM (my return is a single 1 1/2 inch PVC pipe; the previous owners deactivated the other 1 1/2 inch return; the piping around the pump and filter is a single 1 1/2 inch pipe, too, coming from 2 1 1/2 inch suction side)

If I understood yo correctly the power (KW) is proportional to GPM*Head, so I approximate .4 kW in the diagram for 35 GPM/30 ft of head.

GPM Ft head KW
40 40 0.597
35 30.625 0.400
30 22.5 0.252
25 15.625 0.146
20 10 0.075
15 5.625 0.031
10 2.5 0.009

If I run this baby 18h at 15 gpm and 2 h at 35 gpm per day, I'll use 41 KWH per month instead of 410. In a 5 month season (yes, I use the pool if the water is warmer than 67 deg here on Long Island, NY) . At $.195/kwh that's a savings of $358 per season !

Can this be true ?

Patrick