DC pumps:huge power savings, really?

[gridley]

I'm certainly no electical enginer, but when choosing my pumps I spoke with an electrical enginer. His recommendation - without hesitation was to go with DC equipment if possible.

Questionable water flow ratings from manufactures aside, a DC pump will use less power to move an equal mount of water compared to an AC pump. DC is more efficient. One advantage of DC is that the speed of the pump can be controlled thereby reducing the power consumed. An AC pump is either on or off - full power use or nothing. A DC pump, if it comes with a speed controller, can be set for a lower speed (lower wattage use) if you do not need the full water flow. I have my Waveline 5000 set at the third of six speeds which provides me with plenty of water flow and uses half the full wattage (approx 20 watts).