Solar Heating for Pool – seeking product and contractor recommendations

[bibsoconner]

Thanks for the comments ocrenter and others. For those following this thread, I’ve done some research which I think anyone with a passing interest in solar, pools, or TOU, will find very interesting.

First, if I’m reading the following articles correctly, “Time of Use”, (TOU) can not be forced on the consumers until Jan. 1, 2018 at the earliest. At that time, the PUC is supposed to have a plan in place for mandatory TOU. Of course, that is right around the corner (2 1/2 years). References:

http://www.dra.ca.gov/general.aspx?id=2444
http://nextcity.org/daily/entry/california-allows-power-companies-time-of-use-solar-power

Please tell me if I’m reading them incorrectly.

Then, trying to get even more info, I wrote to the head CPUC (Calif Public Utilities Commission) Commissioner, Michael Picker, to see if he could give some guidance as to what will happen with TOU. To his credit (and my surprise!) he wrote back. I’ve copied the exchange below. I’m not inclined to wait until June 21st to make a decision on whether or not to get solar for pool. As Mr. Picker alludes to, the vote might be delayed. I think I’ll just hope that they are wise enough to take into account that there are a lot of folks with pool solar heating.

Comments, advice, flames welcome as always.

-Dave

Me:
Dear Michael Picker,

I am hoping you can answer a simple question that I could not get resolved by contacting SDG&E nor the PUC help line (800-649-7570).

I am considering putting in solar heating for my pool. As you know, the water in a pool must be circulated and it requires very little extra electrical power to pump the water to the roof where it can be heated by the sun for free. Currently this is a much cheaper option than heating with natural gas, once the initial investment (~$6000.00) is made. However, if “Time of Use” (TOU) was to become mandatory, this would no longer be the case. Currently, I am able to change my hours for pumping the pool water to anytime during the day or night, but with solar heating, the pumping must be done during the hottest parts of the day (typically 11am-5pm).

Do you know if TOU will become mandatory and if so, when? Do you know if there will be any provision for pool owners who are trying to save energy (and money) by using solar heating?

I have contacted SDG&E. They referred me to the PUC help line. Their answer was that “no one knows the minds of the commissioners and there is no way to find out”. I refuse to believe that is the case in a democracy. The commissioners answer to the governor, who answers to the citizens.

I appreciate your help in this matter.

Sincerely,

Michael Picker:

We are in the midst of a proceeding regarding rate reform, and will decide if and when TOU pricing will be mandatory as part of that. Currently, that matter is scheduled for a vote on June 21. But things change and get delayed…

Commissioner Michael Picker
California Public Utilities Commission
505 Van Ness, Fifth Floor
San Francisco, CA 94102
(415) 703-2444
[email protected]

And, the state constitution says that we are independent decision makers, appointed by the Governor, and confirmed by the Legislature. We are a quasi-judicial agency, and, for many decisions, have a painful and complex process of hearings, and make our decisions based on the published record, as a panel of judges would. So, in most respects, SDG&E is correct.

Commissioner Michael Picker
California Public Utilities Commission
505 Van Ness, Fifth Floor
San Francisco, CA 94102
(415) 703-2444
[email protected]

[ocrenter]

[quote=bibsoconner]Thanks for the comments ocrenter and others. For those following this thread, I’ve done some research which I think anyone with a passing interest in solar, pools, or TOU, will find very interesting.

First, if I’m reading the following articles correctly, “Time of Use”, (TOU) can not be forced on the consumers until Jan. 1, 2018 at the earliest. At that time, the PUC is supposed to have a plan in place for mandatory TOU. Of course, that is right around the corner (2 1/2 years). References:

http://www.dra.ca.gov/general.aspx?id=2444
http://nextcity.org/daily/entry/california-allows-power-companies-time-of-use-solar-power

Please tell me if I’m reading them incorrectly.

Then, trying to get even more info, I wrote to the head CPUC (Calif Public Utilities Commission) Commissioner, Michael Picker, to see if he could give some guidance as to what will happen with TOU. To his credit (and my surprise!) he wrote back. I’ve copied the exchange below. I’m not inclined to wait until June 21st to make a decision on whether or not to get solar for pool. As Mr. Picker alludes to, the vote might be delayed. I think I’ll just hope that they are wise enough to take into account that there are a lot of folks with pool solar heating.

Comments, advice, flames welcome as always.

-Dave

Me:
Dear Michael Picker,

I am hoping you can answer a simple question that I could not get resolved by contacting SDG&E nor the PUC help line (800-649-7570).

I am considering putting in solar heating for my pool. As you know, the water in a pool must be circulated and it requires very little extra electrical power to pump the water to the roof where it can be heated by the sun for free. Currently this is a much cheaper option than heating with natural gas, once the initial investment (~$6000.00) is made. However, if “Time of Use” (TOU) was to become mandatory, this would no longer be the case. Currently, I am able to change my hours for pumping the pool water to anytime during the day or night, but with solar heating, the pumping must be done during the hottest parts of the day (typically 11am-5pm).

Do you know if TOU will become mandatory and if so, when? Do you know if there will be any provision for pool owners who are trying to save energy (and money) by using solar heating?

I have contacted SDG&E. They referred me to the PUC help line. Their answer was that “no one knows the minds of the commissioners and there is no way to find out”. I refuse to believe that is the case in a democracy. The commissioners answer to the governor, who answers to the citizens.

I appreciate your help in this matter.

Sincerely,

Michael Picker:

We are in the midst of a proceeding regarding rate reform, and will decide if and when TOU pricing will be mandatory as part of that. Currently, that matter is scheduled for a vote on June 21. But things change and get delayed…

Commissioner Michael Picker
California Public Utilities Commission
505 Van Ness, Fifth Floor
San Francisco, CA 94102
(415) 703-2444
[email protected]

And, the state constitution says that we are independent decision makers, appointed by the Governor, and confirmed by the Legislature. We are a quasi-judicial agency, and, for many decisions, have a painful and complex process of hearings, and make our decisions based on the published record, as a panel of judges would. So, in most respects, SDG&E is correct.

Commissioner Michael Picker
California Public Utilities Commission
505 Van Ness, Fifth Floor
San Francisco, CA 94102
(415) 703-2444
[email protected][/quote]

Interesting stuff. Mandatory TOU will totally push more homeowners to solar. Sounds like it is the CPUC pushing for it instead of SDGE. I guess that makes a lot more sense.

[Doofrat]

I’ve done a lot of work tuning the schedules on this pool and here’s what I’ve found:

Luckily, the controller lets you set the exact RPM for whatever task the pool is doing at the time and reports back the KWh being used.
To run the cleaner or to run the solar are about equal in RPM.

At 2300 RPM / 635 KWh , I can run either the solar with skimmer or the cleaner with skimmer.

I can get the solar by itself down to about 2050 RPM /500 KWh if I run it with no skimmer or cleaner

Solar by itself seems to require about 300-400 RPM to get the same flow as without.

If I run the Skimmer, cleaner, and solar together, the required RPMs jump up quite a bit to near 3000 and you push up to 1000 – 1200 KWh. I might be able to get this down a bit by priming the system at a higher RPM so the return doesn’t suck air, but I don’t think I will.

The schedule I’ve set then is:

1. Run just solar during the day at about 500 KWh. I run it for what is needed, which is only a few hours a day, I just change the schedule each night depending on weather the next day (That’ll get old real quick), but it’s only 3-5 hours required, but once I change out the system’s thermometer (It’s broken), it can handle the solar automatically.

2. I run the cleaner at night (currently 6:30pm to 11:30pm)

Total energy usage is:
2000 KWh for solar during the day
3000 KWh for the Cleaner at night

Remember that the water is still going through the filter while solar is running, so I’m currently getting about 8 hours of filtering a day.

[bibsoconner]

[img_assist|nid=20920|title=Usage for May 29th|desc= As you can see there are 2 peaks in the day. The peak starting about noon is when the pump is on high (speed 3). The other peak is when we come home from work/school. Cheers, Dave|link=node|align=left|width=100|height=75]

[bibsoconner]

Sorry that got cut off, and I’m not sure how to display that image of one day’s electrical usage. But the upshot is that there are peaks around 9am to 12 noon when the pump is on high (speed 3) and another at about 6p.m. to 9 p.m. when everyone comes home from work/school.

Thanks for the calculations Doofrat, although, I’m not sure I understand your numbers. I assume they are for monthly use? And even then, they seem high. Perhaps you meant Wh, not KWh? My total electrical usage for May was 562 KWh.

I’m trying to add an image that shows a typical weekday use for us.

As you can see there are 2 peaks in the day. The peak starting about 9 amis when the pump is on high (speed 3). The other peak is when we come home from work/school.

Cheers,

Dave

[Doofrat]

I meant Watts in the beginning and KWh at the end. I was calculating out what all this equipment was going to cost for electricity (haven’t gotten my first bill yet), so I had KWh stuck in my head 🙂

I need to run the filter for 8 hours a day in the summer.

With my equipment, to run everything (Solar/Pool Monster/Skimmer/Filter) at the same time seems to use about 1200 Watts of power, or 9.6 KWh per day on an 8 hour schedule. This would cost about $129 on the 4th tier.

I broke down what each component was using power wise:

When I run solar/filter, it uses about 500 Watts.
When I run Monster/filter, it uses about 600 Watts
When I run solar/Monster/Filter, it uses about 1200 Watts

Instead of running all this together for 8 hours a day, I split it into two groups:

1) A shorter solar period with just filter/solar/skimmer (3 hours)
2) A longer pool monster period during the evening(5 hours)

Running the Solar/filter for 3-4 hours during peak sunlight hours uses 2 KWh each day.

running the cleaner (the pool monster) at night for 5 hours uses 3 KWh.

So 5 KWh per day is used as opposed to running everything for 8 hours together which would use almost 10 KWh per day, this should only cost about $60 a month in the 4th tier of pricing.

I still get 8 hours of filtration, but only 5 hours of pool monster, which still gives it a chance to make several passes over the bottom of the pool, and 3-4 hours of solar which keeps it a toasty 87 degrees right now.

So I don’t think TOU restrictions will cause much harm to the wallet if you just run solar during the day and then run the cleaner during the night.

[LAAFTERHOURS]

New pool owner here. I bought a solar cover two weeks ago (over-sized that I cut to size) and installed the thing in about 10 minutes. Cost on amazon was about $170. Its a blue bubble cover 12 mil. I keep the cover on all the time unless we are going to swim or do my weekly scrub and vacuum. I can pull the cover and fold it up in 10 minutes on my own. I can pull it back onto the pool on my own but with my 8 yr old it takes about 5 minutes.

In terms of performance, my neighbor has a smaller pool and has solar panels on the roof cycling his water (both pool and panels are roughly a year old and all of our specs other than size are the same). I cover both the pool and the spa that dumps its water into the pool for 8 hours a day. I open the skimmer 75% (close the robot to 25%) and open only the floor return. I am not sure if this is helping cycle the water from the top of the pool through the bottom but its what I am doing. Last Friday, my pool temp (on the heater and the floating temp gauge) was 78 degrees. My neighbors hit 78 as well that day. Today, my temp is at 84 degrees while my neighbors is at 82.

Im not telling you to avoid solar because I will probably put it in eventually but the other benefits of the cover are things to consider. The chlorine stays constant with the cover on, the heat loss at night is non existent and I have not added water to the pool since I put the cover on. The last point on evaporation is huge considering our water restrictions.

[bibsoconner]

Thanks LAAFTERHOURS,

I agree that pool cover helps a lot. We have an automatic one (which I don’t particularly recommend as it’s prone to breaking at the most inopportune times, and it certainly cuts back evaporation and helps keep in the heat. But I never felt our pool was warm enough except in the hottest parts of the summer. Might depend on where you live. We’re in Pt. Loma, so closer to the coast and colder. And of course, it tends to be more overcast/foggy, which is also a factor for solar heating.

[Doofrat]

When it’s overcast, as long as it’s not too windy, you’ll get a very marginal increase in the pool temp with solar – Maybe a degree or two throughout the day if you’re lucky, but when it’s sunny, you’ll get around a degree an hour from what I’ve seen.
I have a pool cover, but haven’t used it yet and I’m losing about 4 degrees a night in the last week.

[LAAFTERHOURS]

I live in San Elijo Hills so not as much marine layer as point loma but most days last week were foggy. Since about last Friday, we have had sun daily. I just ran my chem tests and checked the temp and its 83 degrees.

[bibsoconner]

For those following this thread you might find this q&a link, which I initiated interesting:

http://diy.stackexchange.com/questions/67057/is-solar-heating-of-pool-worth-it-especially-after-time-of-use-tou-electric-r

Notice the mention of solar pumps.

-Dave

[LAAFTERHOURS]

I should probably know this but is there currently any benefit to running your pump during the day vs at night? I dont mind running mine all night (would probably prefer it as it wont be on during the day while I am outside) but I am not sure if it matters until the time of day rates hit.

[bibsoconner]

As long as you are not on Time of Use (TOU), I don’t think there is much difference between running during the day vs. night. If your pump makes a lot of noise during part or all of the pumping, your neighbors might prefer that it happens during the daytime vs. 3 in the morning.

[LAAFTERHOURS]

Any idea if salt collecting on top of the cover is bad for it? I may need to trim my cover more as some water is seeping on top and once it dries, salt residue is left behind.

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