Water Pump Electrical Usage


Old 01-24-03, 04:50 PM
Visiting Guest
Posts: n/a
Water Pump Electrical Usage

25 January 2003

I am trying to come up with a “guesstimate”/approximate figure for typical monthly electrical usage to run a water pump for a pressure tank. I know that it is not a large amount, depends on usage but need a figure for an explanation to give a small claims court judge in a Landlord/Tenant suit. I’ll try to explain situation.

This is in a duplex, 2-unit rental on one acre in southern Michigan. One unit has 1 full bath and the other has 2 full baths, a water softener and a dishwasher. Also had 2 clothes washers and an underground sprinkler system in the front yard covering 15,000 sq ft (4 zones w/ 3-4 heads) which may have run daily this past summer (3 months). Additional lawn watering in other areas by traditional sprinklers. Occupants in the building were 2 women, 2 teenage girls and 1-2 other occasional people.

The pump is submersible type and believed drilled to about 160 ft to hit water. I can not find any literature to give you more details. The pressure tank is a Well-Rite Series Diaphragm, 33 gal capacity, model #WR120-04. Water-saving aerators were on some of the fixtures and all 3 toilets were low 1.6 gal per flush

This building has 1 well, 1 pump and 1 tank. I need to get an idea of how much money one tenant pays for all the water in the building. . I think the former tenant may feel that water tank w/ submersible pump was creating high electric bills-I think it was her 2 window AC units.

I am guessing in the summer w/ lawn water it was approximately $10 a month for the whole building and maybe $5.00 the other months at $0.08 a KW. What do you think?

I am thinking that the pump probably is no larger than ¾ horsepower. With 1 horsepower=746 watts, that’s ¾ hp=560watts. Then, 0.560 X $0.08 (1 KW)=$0.045 per hour. That’s 4.5 cents an hour-less than a nickle. Then calculate # of hours pump ran.

Also, is the 560 watts per actual, accumulated 6o minutes that the pump is running (between cut-in and cut-out) or is it clock time, say noon to 1:00. Pumps, furnaces and others do not run continiously-they come on and off.

Thank you for your time.

Last edited by sparkie; 01-24-03 at 05:59 PM.
Sponsored Links
Old 01-24-03, 08:37 PM
Join Date: Jun 2002
Location: Brethren, Mi
Posts: 1,648
Received 0 Votes on 0 Posts
I am not going to fig it out but I think you are probably right and lots of those are 1/2 hp so your fig of 3/4 hp is probably good. 2 window units going full blast would certainly use considerable power.
Old 01-24-03, 09:03 PM
Master Electrician
Join Date: Dec 2001
Location: Indiana
Posts: 300
Received 0 Votes on 0 Posts
You have done a great job so far.
Tha caculation you would use is.
Cost = Watts x Hours Used x Rate Per Hour / 1000
To be fair devide that into the people using it.

Watts = Volts x Amps

Hope this helps....

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: