This may be over simplifying, but it seems like the 2 hp pump would use 2x the electricity and deliver not quite 2x the water (2hp:1hp and 50:27 gpm), while the 3 hp pump would use 3x the electricity for 2 2/3 the water (3hp:1hp and 80:27 gpm). If you are delivering the same amount of water over a 24 hour period, I think running the 1 hp pump would be cheapest.

I wonder if it would be possible to run a very small pump just to pressurize water for the house from the 1 hp pump feed to the pond. I've never heard of anything that that being set up. If possible, this should cost less than getting a 2 or 3 hp pump.

"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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