WOW!!! Filter run time and electric cost.
We just finished our first month with our new IG pool. It is a small pool approximatley 12x29 with the shallow end at 3 feet and the deep end at 6 feet. My question is, I ran the filter a Jandy 60 DE filter with a Jandy 1hp pump four hours a day. I live in California, and my one month electric bill was $218.00 as opposed to my pre pool bill which was usually around $75.
I know that our electric out here is expensive, but wow. I did not calculate such an expense, as my research did not show that the filteration was that expensive. I also know that I will have to run it twice as long in summer, which means an even higher bill.
Can someone tell me if this is normal?
Thanks
Re: WOW!!! Filter run time and electric cost.
That does not sound normal to me. I barely noticed a bump on my power bill when we started operating the pool we had completed a few months ago and that included about six weeks or two months of 24x7 operation with a 2 HP pump.
You can calculate the expected electrical usage of your pump fairly simply. Determine the wattage (or kilowattage) by multiplying the voltage (probably 220) by the current draw (in amps) and then multiply that by the number of hours per day (or month or year) that the pump operates to calculate the number of kilowatt hours you're consuming in a given period. Multiply that by the cost per kilowatt hour to determine the cost for that period.
Have you been using the light(s) much? I imagine that a 500W incandescent could account for some of the abnormal increase you're seeing.
Re: WOW!!! Filter run time and electric cost.
A horsepower is about 3/4 of a kilowatt, so if you can find your utility's KWH rate, you can estimate what the filter costs to operate. It will cost you about 3/4 of that KWH rate to run your pump an hour. Your bill seems way out of proportion to anything a pool pump could do.
Re: WOW!!! Filter run time and electric cost.
746 watts per HP is a theoretical number assuming 100% efficiency which isn't the case. Actual power consumption is somewhat higher. In May 2001 I measured the current for my 1 HP 1997 vintage Hayward superpump and it was about 7.5A measured with a clamp-on ammeter, relates to 1800W. Don't know what the power factor correction is which would reduce the actual power somewhat. That was at a filter pressure of 15 psi, least flow restriction. If you really want to measure the power for the pump, the best way is to use the watt-hour meter for the house. I'd have to refresh my memory but you can count the revs of the disc in the meter and the meter has a calibration in watt-hours per rev or something like that. I forget how the specs are stated.
Al
Re: WOW!!! Filter run time and electric cost.
Al, you are right that this isn't accurate. Just remember that the 746 IS an accurate number, but the innacuracy comes from the inefficiency of the electric motor itself. Rated HP X Service Factor X Pump Hours X Utility KWH rate will give a close estimate of daily cost. To be very accurate, Motor Current X Motor Voltage X Pump Hours X Utility KWH rate divided by 1000. It's a little easier to do the HP one in your head.
Re: WOW!!! Filter run time and electric cost.
Thank you all for your responses, I did not think the filter and pump could cause such a spike.
One response listed that the pool and spa light could be a factor. I have been running the lights each night on a timer for 3 hours, along with approximatley 300 watts of low voltage lighting. I did not think that even this could cause such a spike, however I will turn them off and see what the next bill brings.
Thanks
Re: WOW!!! Filter run time and electric cost.
I agree this did not sound right BUT you need to remember that several states did have a HUGE electrical rate increase. I was watching a report just a few days ago and one state electric was increasing by 100%! The average was about 75%.
I am not saying this is the reason her bill is so high but I am betting there are several factors involved.
Re: WOW!!! Filter run time and electric cost.
This wan't asked or stated but did this new pool install have a water heater?
Re: WOW!!! Filter run time and electric cost.
A pool should cost about a buck a day - so make it two bucks a day with electricity cost increases...
Re: WOW!!! Filter run time and electric cost.
I too live in California and currently run my 1 HP Northstar 3 hours a day. One thing to remember is the true HP of a pump is the labeled HP times the service factor. For my pump, I have a 1.85 service factor which means my braking HP is really 1.85 HP. Also, from the manual, the service factor amps is 8.0 @ 230V. So the pump draws about 1.84 kw which is close to the braking HP and generally used as a rule of thumb for energy usage.
In California, when you draw above baseline usage you get hit hard for electric rates. So, I am paying about $.22 per kwh for the pool pump and $36 extra a month for 3 hrs a day run time. When I double the run time this summer, I should be paying about $72 extra a month.