How much power to run a well pump?

[rmcelwee]

I am extremely new to RE and just wanting to do it as a hobby. Definitely not going off the grid. I would like to start small and then end up powering a few things here and there as my system grows. I recently dug a well for an irrigation system and installed this pump:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=47906

The web page ad says "8.5 Amps" and the documentation that came with the pump says "5 Amps start up". Other than that, I have no idea of the power requirement for the pump.

So my two questions are:

1. How can I figure out what my power draw is on this pump?
   
2. Once I know how much power it uses, I guess I can figure out how much money it costs me (in electric bills) to run it. I know it will take 100 years to break even if I am only running one pump on the system but it is still a number that I would like to know (so I can carry on a conversation about my system). I see from my electric bills that I use around 1800-2600 KWH a month @ about $0.082/KWH. If I am using a 110V pump (see above) what would my cost be to run my pump 3 hours a day, 2 times per week? I'm only asking because you guys can probably figure this out in your head while it will take me an hour to figure it out (first time doing this).
   
   

FWIW, I documented my shallow well installation on my website and will do the same with my solar power:

http://www.lightweightmiata.com/well/

I would like to eventually cool my garage with the cold well water - but that is another project.

[wdyasq]

The numbers can be figures with the information given. They will be as reliable as a politician's promise. You will need a "Kill-a-Watt", "Watts-Up" or an amp meter to read the real draw and get some real numbers.

Good luck,

Ron

[stephent]

And if you can get a 1hp motor to start with 5 amps without jumping through a few hoops--let me know. I might believe 15 amps totally unloaded and with a few controls, but the normal initial surge will be 3 to 5 times normal amp draw for just a few part seconds (and can be way more then that sometimes--especially trying to punch 40 pounds of pressure into the storage tank with a more/less uncompressable thing like water) --that's the bugga-boo bear for an inverter to overcome.

voltage (120) times amps (8.5) times hours used per day times number of days used per week times number of weeks in month times your per KW cost (.082) gives total cost.

But your pump may use the high amp draw (8.5) for a high lift draw of water--it may use less for less lift--use the mentioned Kill-a-watt for your amp/kw calculations and it will be a closer number.

[rmcelwee]

So, if I take my meter out to the pump what do I measure? Not sure what wires to check to read the amps.

[altosack]

The kill-a-watt meter plugs into an AC socket, and you plug your appliance (pump) into that. It will tell you Amps, Volts, Watts, Hours, and (k)Watt-Hrs.

This is great if your pump has an AC plug. If not (it's hard-wired, which is most likely), you need to cut the wires and fabricate your own socket and plug to make this possible. Do not try this if you don't know what you're doing; if you're not sure if you do or not, you don't.

If you just have a multi-meter, this won't help you much unless it's a very good one, and even so, you'll have to fabricate your own wiring to make it work. If you are serious about generating your own electricity, definitely get yourself a kill-a-watt meter; it's about $35 and worth it for the info that it will give.

Dave

[rmcelwee]

Tried to buy a kill-a-watt at harbor freight today but they didn't have them in stock. Might have to get one online.

[rmcelwee]

That works out to be $61 a year for 12 hrs a week at 8.5 amps (just a guess). That isn't much money to build a RE system with!