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View Full Version : Minimize Energy Costs Strategy Needed



larryincanada
01-24-2008, 10:45 AM
Time of day (demand based) electricity rates will be introduced to my area soon. The rates are about 3 times higher during the daytime weekdays compared to weekends and late evenings.

I have traditionally operated my chlorine generator (Aquarite) and pump (1hp) for my inground pool (18'x36') with pressure side cleaner (Polaris 360) successfully on a timer for about 16 hours per day during the daytime (7am to 11pm). I religiously use a solar blanket, so I don't need to use my heater. It has been extremely easy to maintain and manage.

Obviuosly I want to minimize my bills, but I know that the chlorine is used up the most in the sunlight and heat of the day. I want to change the scheduling for the pump and chlorine generator to operate mainly at night and weekends.

Some issues I may have without circulation during the day:
1) exagerrated temperature gradient with solar cover - hot on top and cooler below
2) inefficient passive heating with solar blanket without circulation
3) potentially more visible debris and dirt when pool is in use without active skimmer
4) noisier pool and shed with pump operating all night - may upset neighbours
5) chlorine levels dropping below acceptable in sunlight and heat

Should I bump up the chlorine level in anticipation that it will be depleted during the day? Are there any other pitfalls I should watch out for when I try it out this coming season? Has anyone tried this strategy to run the pool off-peak hours successfully?

Should I take a more conservative approach and operate at intervals during the day and night. ie 2 hours on 2 hours off. What scheduling strategies have worked for others?

Your experience and knowledge is appreciated.

CarlD
01-24-2008, 12:58 PM
A 1 hp pump that's 2 speeds will use about 1/3 the electricity at low speed and is SO quiet you have to be within 6' of it just to hear it. I run most of the time at low speed with no problem. You'll only want the high speed for the cleaner, and that can be programmed in. Me, I have a simple toggle switch on the back of the pump motor, but that's all I need.

Poconos
01-25-2008, 09:47 AM
Larry,
Glad to see someone active on this forum. Carl is obviously right with the two speed pump idea and with rates 3X at peak I'd certainly be thinking of innovative ways to cut power consumption too. I don't use a chlorine generator and have no experience with them but I would see nothing wrong with letting the chlorine level bounce around a bit. Jack it up at night and let it fall during the day. With the right CYA level the daytime drop should be easily manageable. Not like you have no CYA and all the chlorine disappears in an hour. Your concerns about the solar blanket efficiency and gradients without circulation are valid. I don't think the efficiency will be an issue because even with stratified water, hot right under the surface and against the bottom side of the blanket, there is still a lot of heat transfer from both the heating of the cover and infrared penetration. The temperature differential is the key to heat transfer. Simplistically, consider laying the cover on dry ground and see hot hot it gets....plenty. Compare this to the water temp just under and if the water is 80 or 95 the differential will still be very high. Of course a 2-speed pump would eliminate these issues. As for quieting the pump, since you already have a shed there are cheap tricks to shut it up a lot. Mounting the pump on a vibration insulating board, connecting the pipes with radiator hose to cut down noise conduction, and maybe even another ventilated and insulated pump box cover. I can point you to the right threads if you want to pursue this.
Hope this helps.
Al

Phillbo
01-28-2008, 10:40 AM
Do you need to run your pump 16 hours each day to prevent freezing ? I am on a demand type plan as well. 9pm to 9am and weekends is the cheap time. In the winter I only run my pump for 4.5 hours (9pm - 1:30am) and as the summer arrives and the water temp increases I add a second run in the early morning. By June or so I'm running the pump 4 hours at night and 4 hours in the morning max. This systems works best for my pool, provides plenty of time to keep it clean and generate chlorine.

CarlD
01-28-2008, 11:21 PM
I winterize my pool and let it freeze. I don't run the pump from October to May--because it's stored in the basement.

Phillbo
01-29-2008, 11:52 AM
I guess you can't minimize your energy usage any more than that now, can ya :D

CarlD
01-29-2008, 01:02 PM
I guess you can't minimize your energy usage any more than that now, can ya :D

Not unless you can figure out how to get it to generate electricity for ya!

larryincanada
02-10-2008, 09:47 AM
Thanks for the suggestions!

I too, only run in the summer and let the pool freeze in the winter.
Getting a 2-speed pump sounds like a option. I just don't like changing out my almost still new 1hp pump.

I think I may look at getting a smaller pump, say 1/2 to 3/4hp and install it in parallel with a couple of check valves. This should be cheaper than a new fancy 2 speed. I can then power up each of the pumps I want through a timer and have the benefit of a back-up pump. I'll just have to install the proper switches and wiring so as to not have both pumps come on at the same time on the same fused circuit.

It would be great to have the system operate automatically based on the real demand. Are there any devices out there that can automate the need for turning on the salt water generator and pump? I'm imagining that there can be a remote, hopefully wireless, sensor you can drop into the pool that reads the chlorine level and maybe other parameters such as temperature. A reciever/controller can then trigger the pump and clorine generator to come on only as needed.

CarlD
02-10-2008, 04:57 PM
It won't solve your fundamental problem. Your pump is too big for your filter. You either need a bigger filter or a smaller pump.

Sell it on eBay!

gkosin1
02-16-2008, 10:45 PM
I installed a pentair computerize pump earlier this year and it works great. I have about 1 year pay back and then the savings go in my pocket. Go to their web site and use the energy savings calculator and see if it can help you in your case.
Greg

larryincanada
02-17-2008, 10:44 AM
It won't solve your fundamental problem. Your pump is too big for your filter. You either need a bigger filter or a smaller pump.

Sell it on eBay!


I oversized my filter to reduce backwashing frequency.
It's huge Pentair TA100D at 30" diameter and rated at 100gpm.

I assume that a smaller 1/3 to 1/2 hp would be OK with this filter. I'm sure I'll still need to use my original 1hp to provide enough pressure and flow for a proper backwash cycle.

The chlorine generator should be able to self adjust itself with the changing flowrate. I may have to run it a little longer with the smaller pump.

larryincanada
02-17-2008, 11:12 AM
I installed a pentair computerize pump earlier this year and it works great. I have about 1 year pay back and then the savings go in my pocket. Go to their web site and use the energy savings calculator and see if it can help you in your case.
Greg

VERY NICE and SLICK!
The IntelliFlo looks ideal.
Time to save up for this new toy.

Thanks!