Jump to content
Chapala.com Webboard

solar pool


Recommended Posts

We would like to add solar to our large pool and do not want to cover it. We are happy to only use in the hot months. We researched a couple of years ago and the consensus was there was not enough room for sufficient panels for our size pool. Then with much creativity mostly from us it was determined that by building a super structure and using high efficiency panels we could heat our pool.

Unfortunately, the price kept getting higher and the hot season waning and so we decided to postpone it until the following (last) year. My  husband was very sick for much of last year but in the early summer we decided to proceed. Although I have written twice to the original company, I have had no response.

Does anyone have any recommendations as to a solar pool company with high efficiency panels?

Link to comment
Share on other sites

Hi. Sorry that I don't the info asked for, but I would like to share that we do have solar panels (both pool and home) and while 8 panels feeding our rather large home provide enough electricity to run everything, including a 20,000 mini split, pool pump, irrigation system, etc etc, the panels heating the pool -- 3 m X 4 m with a shallow end, a very small volume of water to heat -- are very effective when the months are warm, from mid September through early April the pool isn't usable. 

Our pool panels face due South and our pool is in full sun all day. But when the rainy season starts the new rains dilute the warm water in the pool, and by September the water is decidedly chilly.  Also, the radiational cooling starts to occur. Likewise, the radiational cooling continues until end of March.  We have used a cover and found that it keeps the warm water warm, but it can only do so much.

If I were to do it again I would still build the pool--I call it my "big fountain"--and I would have the solar panels installed, but my expectations would be lower. I had expected my pool to remain as warm as my Florida pool, also heated by solar panels. Not the case.

Link to comment
Share on other sites

Just a thought. What about a solar hot water heater that swapped out its hot water with the pool water once a day. It could be timed to swap and then your pool pump mix it for when you planned to use it.

Or is that what you're already talking about and I just don't get it having never done it?

Link to comment
Share on other sites

Part of the problem with solar panels is their efficiency at various pump speeds. We have solar panels & a continuously variable speed pump, fully programable. If we run it at 900 rpm for 2-4hrs the solar is extremely efficient. Think about the time the water has to heat within the solar panels, longer is better. Water temp can easily go from 76° to 81°±

Link to comment
Share on other sites

12 hours ago, kimanjome said:

Hi. Sorry that I don't the info asked for, but I would like to share that we do have solar panels (both pool and home) and while 8 panels feeding our rather large home provide enough electricity to run everything, including a 20,000 mini split, pool pump, irrigation system, etc etc, the panels heating the pool -- 3 m X 4 m with a shallow end, a very small volume of water to heat -- are very effective when the months are warm, from mid September through early April the pool isn't usable. 

Our pool panels face due South and our pool is in full sun all day. But when the rainy season starts the new rains dilute the warm water in the pool, and by September the water is decidedly chilly.  Also, the radiational cooling starts to occur. Likewise, the radiational cooling continues until end of March.  We have used a cover and found that it keeps the warm water warm, but it can only do so much.

If I were to do it again I would still build the pool--I call it my "big fountain"--and I would have the solar panels installed, but my expectations would be lower. I had expected my pool to remain as warm as my Florida pool, also heated by solar panels. Not the case.

Sorry you were disappointed. All we want is low to mid eighties during the really hot months. After much research I am convinced we can attain that but only with high efficiency panels which I can't find now.

Link to comment
Share on other sites

14 hours ago, nothernewbie said:

We would like to add solar to our large pool and do not want to cover it. We are happy to only use in the hot months. We researched a couple of years ago and the consensus was there was not enough room for sufficient panels for our size pool. Then with much creativity mostly from us it was determined that by building a super structure and using high efficiency panels we could heat our pool.

Unfortunately, the price kept getting higher and the hot season waning and so we decided to postpone it until the following (last) year. My  husband was very sick for much of last year but in the early summer we decided to proceed. Although I have written twice to the original company, I have had no response.

Does anyone have any recommendations as to a solar pool company with high efficiency panels?

The panels we need are a series of piping rather than the traditional solar panels.

ional solar panels.

Link to comment
Share on other sites

It is almost impossible for pool solar panels to heat the water to a swimmable temp. during Nov, Dec, Jan and parts of Feb. Fewer daylight hours and the angle of the sun are mostly to blame.

Link to comment
Share on other sites

The flat black panels work great for most pools, most of the year.    A cover is always a good idea, of course.    For areas where more heating is needed for a given amount of roof space, or due to the size of the pool or lack of cover, there is a higher efficiency option using vacuum tube systems, to produce over 2x the heat per amount of space.     Higher cost as well.    Image here is from a home in Upper La Floresta, with a really large volume pool - this system was installed about 6 years ago, and the owners are very pleased.

A batch tank heater as Ferret mentions could work for a hot tub, however not for a pool - the volumes are not sufficient.     Circulating and heating using the pool as the "tank" is the way to go, no matter what type of solar collector is to be used.

 

Casa C system.jpg

Link to comment
Share on other sites

14 hours ago, kimanjome said:

Hi. Sorry that I don't the info asked for, but I would like to share that we do have solar panels (both pool and home) and while 8 panels feeding our rather large home provide enough electricity to run everything, including a 20,000 mini split, pool pump, irrigation system, etc etc, the panels heating the pool -- 3 m X 4 m with a shallow end, a very small volume of water to heat -- are very effective when the months are warm, from mid September through early April the pool isn't usable. 

Our pool panels face due South and our pool is in full sun all day. But when the rainy season starts the new rains dilute the warm water in the pool, and by September the water is decidedly chilly.  Also, the radiational cooling starts to occur. Likewise, the radiational cooling continues until end of March.  We have used a cover and found that it keeps the warm water warm, but it can only do so much.

If I were to do it again I would still build the pool--I call it my "big fountain"--and I would have the solar panels installed, but my expectations would be lower. I had expected my pool to remain as warm as my Florida pool, also heated by solar panels. Not the case.

Assuming you have roof space available, you can expand the system to cover those needs - casa Bublin did this last year for their new home by adding just 2 more pool panels and saw an immediate and large difference.    Ask Harry & Chris!

Link to comment
Share on other sites

1 hour ago, Mainecoons said:

We have 8 panels and a medium size pool.  They cannot warm it up without a cover and it has been so chilly this year even the cover doesn't help enough to make it swimmable.

 

@Northernnewbie, please refer to MaineCoon's post.  This past year it was difficult to heat a pool, even a small and shallow one like ours,  which had full sun all day. That is because there was a lot of rain, and that volume of cold water reduces the warm water in the pool.  I did enjoy the pool late April, May, and June, and most? of July.  

I am not trying to dissuade you from heating your pool.  I think it's a great idea. I only posted  my disappointment so you, or others who may be interested, understand that no how great a solar system you have, it's not always easy to counteract forces of Mother Nature.

Our Key West home has the flat black solar panels to the pool, which was a shallow, inground fiberglass one about 4' deep and 10k gallons.  Our Sarasota home, about the same dimensions, only needed a November through March boost, so we used a quick adjunct  natural gas heater, which was fabulous. 

Ii would assume that a large number of solar vacuum tubes as in the photo would have an increasingly large volume of heated water to flow into the pool to dilute the cooler rain water. The issue is the time it takes to get all that warm water into the pool. Maybe if the pipes had a larger circumference, or there were double the number of pipes forcing heated water into the pool?  I don't know, I'm not an engineer.

 

 

 

Link to comment
Share on other sites

I was wondering where you were Go Solar. Thanks for answering my question but I had already come to that conclusion after continued reading and calculations.

I was also reading about propane pool heaters and thought that might be a more cost efficient method depending on the size of the pool since it uses the circulating pump that is already there and is quite efficient for a specified time frame. Not, of course, to be used for maintaining the heat 24/7. This is the one that I zeroed in on and a quote from one of the reviews follows the link. https://www.intheswim.com/p/hayward-universal-h-series-pool-heaters#pdp-tab1

Quote

This heater is much lighter than my old one. It was very easy to rotate the heat exchanger since my pool pump is on the left. It took me about 3 hours to install, since this is the first time doing it myself. I wired it up as 110volt ac. My pool water was 65 degrees and within a couple of hours it was up to 85 degrees. So far we are very happy with it and hope it lasts as long as my old one which was 14 years,

Please note that the reviewer does not say how big the pool is... but there are calculators available online to properly size one of these heaters.

Link to comment
Share on other sites

Ferret,

good info, thanks for sharing it.   

Almost all pool heating systems of any type use the pool pump as the circulation method, FYI.  

For propane, the issue is not how fast they work - rather, the amount of energy and ga$ needed to heat a large volume of water.     Think about putting 10,000 gallons of water (typical pool size) on the stove, and raising the temp by 20 degrees F......

Link to comment
Share on other sites

9 hours ago, mkshawn said:

Part of the problem with solar panels is their efficiency at various pump speeds. We have solar panels & a continuously variable speed pump, fully programable. If we run it at 900 rpm for 2-4hrs the solar is extremely efficient. Think about the time the water has to heat within the solar panels, longer is better. Water temp can easily go from 76° to 81°±

As most pool owners need to and want to run their pool pump 4 to 6 hours out of every 24 anyway, to filter the water, this makes solar pool systems an ideal match, actually.     The pool pump sends the filtered water through the panels (or tube heaters) and it then returns to the pool, warmer.     So running from 10 to 4 each day, when the sun is best, achieves both things at the same time.     

Variable speed pumps are great as they save energy and can be run much longer for the same or less $$ - and, as the pool business people say, moving water is healthier water.

In the hotter months, once ideal temps are achieved or no more heating is desired, moving one simple valve allow the pool heating to be bypassed, as well - no real need for $$ auto temp control systems.

In really hot places like TX, systems can be run at night, to help cool the pool - the flat panels act to help radiate the heat OUT of the system.

Link to comment
Share on other sites

For those who don't like the look of a pool cover to conserve heat...

Liquid Solar Blankets:

Alternatively, products like COVERfree work the same way that solar covers function, but with a chemical instead of a cover. COVERfree creates an invisible barrier that enables heat generated from sunlight to warm your pool water. The thin layer also reduces evaporation, preventing the heated water from escaping.

Go Solar, yes it can be expensive to run a propane heater depending on use. But it is an option for those who don't have the roof space or correct orientation or as a boost for those chilly months. From this website... https://www.inyopools.com/Blog/how-much-does-it-cost-to-run-a-pool-heater/

 

Quote

 

Propane Pool Heaters

You can figure about 1 gallon per hour per 100,000 BTU’s to operate a propane pool heater. For a typical 400,000 BTU heater, that’s 4 gallons per hour. Currently Propane runs about $2.50 per gallon, propane prices do fluctuate so keep an eye on this website updating the National Average Cost of Propane. In our example, 1 hour on propane will cost $10.00.

 

What is difficult to find is some kind of correlation between volume of water at a certain temperature heated to a preferred temperature using an X sized btu propane heater = volume of propane required. That would be a nice comparable to base a decision on.

I loved your post about the use of the solar panels to "cool" the pool at night. I sure could have used those in the summer in San Pancho where the temperature of the pool hovered at 95 F. 24/7

Link to comment
Share on other sites

Another good option to both retain heat, and make heat; these work like a thermo-pane window, letting in the sun's energy while preventing heat and evaporation loss.      They don't really replace a primary heating system, however can very nicely augment one.

http://solarsunrings.com/intro.html

Pros are that they are quite easy to use and remove by one person, and that unlike most covers, they do add heat to the pool.     Also, you don't need to remove them all, to swim.    And you don't need to cover the entire pool surface, either, for good results.

Cons are that they must be in the shade when not on the pool, and like any cover, need to be replaced periodically.   About the same cost as a high quality pool cover.    Pool needs to be in the sun to achieve the heating part of what they do, of course....!

 

 

Link to comment
Share on other sites

Interesting discussion. We have a lap pool 11 metres by 2.5 meters average depth 4.5 feet, volume approximately 9700 litres. With a variable speed pump running 6 hours per day, 10 of the thin flat black solar panels and a standard solar blanket, our pool at this moment is 88 degrees. Definitely warm enough for us to swim.

Link to comment
Share on other sites

That is perfectly sized, plus the cover benefit.    

For anyone interested, the calcs work like this with the 4.5 feet converted to meters

pool volume:   11 x 2.5 x 1.4 =  38,000 liters (38 m3) or 9700 gallons

Each standard size panel is rated at about 4 to 4.5 m3, so 10 should cover up to 40 m3 easily, plus they have the cover to "keep what they make".

No polar bear swims for this casa!   😉

 

Link to comment
Share on other sites

On 1/22/2019 at 5:44 PM, nothernewbie said:

We would like to add solar to our large pool and do not want to cover it. We are happy to only use in the hot months. We researched a couple of years ago and the consensus was there was not enough room for sufficient panels for our size pool. Then with much creativity mostly from us it was determined that by building a super structure and using high efficiency panels we could heat our pool.

Unfortunately, the price kept getting higher and the hot season waning and so we decided to postpone it until the following (last) year. My  husband was very sick for much of last year but in the early summer we decided to proceed. Although I have written twice to the original company, I have had no response.

Does anyone have any recommendations as to a solar pool company with high efficiency panels?

My pool is 70,000 L and I have 8  of the 4'x12' Israeli panels. I cover the pool as that is the only way too keep the pool above 86 degrees 9 months of the year. In just didn't have roof space for more panels. I bought my panels on ebay USA and drove them down to Ajijic. Just any plumber could install. They charged NO duty or tax at the border. Panels cost about $100 each.They all eight fit in a big SUV. They are in boxes about 49"X10"X10" each. If you use a roller the cover is easy to remove and reinstall.

Link to comment
Share on other sites

Top quality flat pool panels (like Techno Solis, used all across lakeside both residential and condo / commercially) are 4 feet wide and rated at about 4000 BTU per foot of length.   So a 10 foot panel rates at about 40,000 BTU per day,  and a 12 foot panel at 48,000 both are daily figures.

So to compare to Ferret's link, a 400,000 BTU heater costs 2500 US, and 10 of the 10 foot flat black Techno Solis panels also equal 400,000 BTU and cost would be about the same., both as the equipment purchase cost.     Installation additional on both.

Differences from there:     The pool panels have a 10 year warranty and no ongoing fuel needs or maintenance costs, and cause no damage to the environment from burning massive amounts of fuel.     Sun is required of course.....

The propane / natural gas heater does heat faster; people who have had both like the slow, steady, and "long term free energy" approach.  

Link to comment
Share on other sites

Unless I missed it, I didn't see mention of heat loss from wind when trying to size the heating requirement. Yes, there was talk about a cover when the pool is not in use. But if you are in a windy location without structures to help block the wind, you may need to consider heat loss from wind in your sizing.

Link to comment
Share on other sites

Evaporation is the largest cooling factor on a pool, outside of the ambient air temps.    Wind does affect evaporation, though as we learned from the thread on the wind generation potential (or lack thereof) at lakeside, the average wind speed of 1 mph isn't a big factor.

And the highest evaporation occurs in the driest months of April and May, when it is hottest, so there's much less of a pool cooling issue at that time of the year.  

What does occur at that time, between the really low humidity and hottest & longest sun days, is a loss of as much as 1 inch of water level, per day.    A lot of folks begin to think their pool has a crack, leak, or drain malfunction.      Also - don't add more salt to the pool, if there is a salt cloro system - the salt is still there!, only the water has gone "away".     Covers also really help to mitigate this issue and save on the water bills.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...