Going Solar need your help

[towney]

We are having a Solar Heater rep coming today. Are there things I should be looking at and questions to ask? Are there different types of panels to consider? What's the best? Thanks

[tphaggerty]

Go to www.powermat.com as a starting point. The website is busy but extremely detailed (***uming that you are going for a permanent installation) and you will learn a lot. I can also recommend looking at the Solar Living Inc. website (www.capturethesun.com) and the www.flasolar.com website. All have good info.

I would come back here with the rep's recommendations and those of us with solar can review.

Mainly, you are interested in the things you would with any normal contractor (reliability, insurance, references). I would also ask for references that you can go see the job, solar can look really ugly, or not so bad depending on the install. You will want an automatic controller for any sizable installation. While I wouldn't go overboard, I would recommend getting as much coverage as possible for your budget and area, its more expensive and h***le to add panels or banks.

I would throw out a few terms that you learn about on powermat.com, like "drain back" and vacuum breaker. I would ask them if they plan to tilt the panels so that the air purges correctly and the water can run out for winterizing (all after they explain things to you first). I would do all of this just to see how knowledgeable they are. Again, come back with recommendations and impressions. Good luck, solar is wonderful.

[towney]

Ok, I have narrowed the field down to two companies. Placement of the panels would have to be on the West side of roof and north side, this is the best solution with respect to the sun. In the winter the sun is at the front of our home and the summer at the back. They both said max sf of paneles on the west side would be 300sf and 76sf on the north (not sure what this means though) with an average temp increase of 10-12 degrees, ideally they would have wanted 400-450sf. Ideally we'd like to extend our season into mid Nov. here in FL with a pool temp of 80 degrees. Of course we would purchase a solar cover (any suggestions on what is the best one) and keep it over the pool when not in use. Does anyone else have any other input or suggestions? Maybe a Heat Pump? Pros and Cons....


Solar design layout:

Pool has 430 sf surface area
Westside of roof~ (4) 1/2 4X10 1/2 panels and (3) 4X9 1/2 panels
Northside ~ (1 3/4) 4X10 1/2 panels

Total solar surface area of 376 sf.

[tphaggerty]

I would ditch the north facing panels. According to everything I've read, panels that are much north of direct east/west are a waste of money. Maybe it is different in FL, though.

Seems to me that the if you really are getting 300 sq/ft of panels on a 430 sq/ft pool, you should easily get your pool up into the high 80s for most of the year in FL. (I can't figure out how you are winding up with 300 sq ft based on 4 4x10 panels, maybe I am incorrectly reading what you wrote). I think the year round part is what drives solar installers in FL to add more panels than we would here in NY. That would give you close to 70% coverage, which is generally considered more than adequate.

A good heat pump is certainly an alternative. Generally, it is a bit more expensive to install (if you get a really good one) and it costs more to run, but it may be your best option. There are solar panels that are built directly into the pool deck, one of the forum members has them, perhaps that would work as well.

[towney]

I would ditch the north facing panels. According to everything I've read, panels that are much north of direct east/west are a waste of money. Maybe it is different in FL, though.

Seems to me that the if you really are getting 300 sq/ft of panels on a 430 sq/ft pool, you should easily get your pool up into the high 80s for most of the year in FL. (I can't figure out how you are winding up with 300 sq ft based on 4 4x10 panels, maybe I am incorrectly reading what you wrote). I think the year round part is what drives solar installers in FL to add more panels than we would here in NY. That would give you close to 70% coverage, which is generally considered more than adequate.

A good heat pump is certainly an alternative. Generally, it is a bit more expensive to install (if you get a really good one) and it costs more to run, but it may be your best option. There are solar panels that are built directly into the pool deck, one of the forum members has them, perhaps that would work as well.

Forgot to put in that there are (3) 4X9 1/2 panels also going on the West side.

So putting the extra panels on the north side would be a waste? They will do this for me for an extra 200 bucks. Would having this extra panels give me any extra benefit in heating. They are telling me I should expect a 10-12 temp increase.

[tphaggerty]

From what I've read, no, the north facing panels really won't contribute to the heat generation. I tend to be an advocate of "get more early" for solar panels. Mainly because I've learned the hard way. I am in the process of adding a 2nd bank, not so much for absolute temp increase, but for quicker heat recovery after bad weather. But, north is just not good with solar panels, the sun is not on them long enough.

However, the angle of the roof definitely makes a difference. If you have a flatter roof, maybe it will work. I don't think it will hurt. Push come to shove, I think I would do it for 200 bucks.

One thing you might consider is going to powermat.com and looking at their powerstrip line. These can be custom cut and constructed so they can often provide more coverage (they be setup to follow roof angles, etc.). You might be able to use more of your roof with these.

[towney]

Need a little extra now. I've had another solar rep come to give their opinion and what I'm getting is max panels is 7 where 12 is needed. He put his honest opinion forward and said the best resuls to heat the pool would be a heat pump. Suggesting a Aquatherm 114K BTU. Now he mostly does solar with heat pumps secondary, so I'm thinking he's giving an honest opinion. Any thoughts on a heat pump vs solar. I know a heat pump will have an operating cost but I'll get more then a 8-9 degree increase with solar. Thanks

[CarlD]

Panels can face East or West, but North is a waste generally. But watch where the sun is. It moves South in the winter, and North in the summer. For me the difference is SIGNIFICANT and I turn panels on and off accordingly.

Solar heat isn't just "heat". You have to decide what you what it for, when you want it, and how much you want. Typically, salesmen tell you the panels should have a surface area near that of the pool. Like all things, this depends on what you expect of them. My panels are only about 35% of my pool's surface but they do GREAT because of what I expect them to do: Extend my swimming season to early May and mid-to-late September, and warm the pool during the summer so it isn't a shock to get in--and that's living in Northern NJ.

Most solar systems have the advantage of being easily expandable--especially the rollable panels--so you can always make a small system bigger if it is not adequate.

Solar's BIGGEST advantages are that it is basically free to operate--just the pump, but the heat is free, and it can double as a cooling system merely by running it at night. It's disadvantage is that it doesn't work without sun, or in the rain.

After having tried the opaque blue-on-top, black-on-bottom cover, the transparent blue cover, and the totally clear heavy-weight cover, I like the last best. Heavier covers insulate more and take longer to pop their bubbles. Clear covers allow the sunlight to penetrate the water and heat it directly, rather than trying to use conduction and convection currents.

Last, if you get a reel, get a good one, a metal one. I don't like the plastic ones--I had the plastic bearings self-destruct, making it hard to turn, and then the handles broke!

[towney]

Panels can face East or West, but North is a waste generally. But watch where the sun is. It moves South in the winter, and North in the summer. For me the difference is SIGNIFICANT and I turn panels on and off accordingly.

Solar heat isn't just "heat". You have to decide what you what it for, when you want it, and how much you want. Typically, salesmen tell you the panels should have a surface area near that of the pool. Like all things, this depends on what you expect of them. My panels are only about 35% of my pool's surface but they do GREAT because of what I expect them to do: Extend my swimming season to early May and mid-to-late September, and warm the pool during the summer so it isn't a shock to get in--and that's living in Northern NJ.

Most solar systems have the advantage of being easily expandable--especially the rollable panels--so you can always make a small system bigger if it is not adequate.

Solar's BIGGEST advantages are that it is basically free to operate--just the pump, but the heat is free, and it can double as a cooling system merely by running it at night. It's disadvantage is that it doesn't work without sun, or in the rain.

After having tried the opaque blue-on-top, black-on-bottom cover, the transparent blue cover, and the totally clear heavy-weight cover, I like the last best. Heavier covers insulate more and take longer to pop their bubbles. Clear covers allow the sunlight to penetrate the water and heat it directly, rather than trying to use conduction and convection currents.

Last, if you get a reel, get a good one, a metal one. I don't like the plastic ones--I had the plastic bearings self-destruct, making it hard to turn, and then the handles broke!


Thanks Carl
I would be getting approx. 75% of my surface area. I'd love to be able to extend season to mid Nov (Florida). If I go heat pump I could heat pool year round, but at a cost. The panels would amount to 7 on my West side. Any thoughs on heat pump?

[RavenNS]

Heat Pumps are awesome!
Everyone I know (locally) has closed up over a month ago; we're still swimming ( even though we've already been having "frost" at night & the leaves have half changed already)

Being that you're in florida, you could literally swim all-year-round :D

If you have the cash, I'd go with solar panels & a heat pump.
just set the heat pump to the "minimum" temperature that you like to swim at...
& let the solar panels bring it up to what you really like the temperature to be at ...

Happy Swimming :-)

( I'm so envious... wish I could swim year-round...lol)

[CarlD]

I don't know much about heat pumps--just a little. Pool heating is an ideal application--the outside air is warm (in heat pump terms--in the 50's or higher) so they get into their super-efficient range, far more so than gas.

H/Ps have a bad rep because they were used for heating and cooling houses in Northern Virginia (near DC) where it's far too cold for them to be efficient in the winter. But for pools they are supposed to be terrific.

They are expensive to install--2 to 3x what a gas heater costs, but far more efficient. If you need to heat a pool fast, though, they aren't so good--gas is better. But keeping it warm? I gather they can't be beat.

Are they better than solar? In some ways yes, in some ways no.

If you can do both, it would be great. You are in Florida, though, where you get lots and lots of sun.

[TMan]

One question about the return line - Ive noticed in the ads for the prebuilt panels (the kind they show on the ground, standing tilted near the side of an AG pool) that the return lines are flexible pipe.
Can you use the flexible return lines like most AG owners have currently? Isn't the water too hot for flex? I was planning to use my current flex so I don't have to buy any more fixtures but was thinking about the heat?
I'm currently in the 'build' stage of my home built solar heater.
We get over 300 days of sun here in AusTX and we stopped swimming 2 weeks ago, just because we got 2 'cold' fronts and temps dropped into the mid-80s during the day. Yesterday it was 90+ and today it will be also, 9hrs of sun. I'm using 1/2" poly pipe off a 5-outlet header into 50' of hose each, 250' of hose, coiled in a used hard pvc pond (empty of course). With the sun I'm hoping for an added boost of 2-3deg. to current pool temps of 75-77. Night temps in the upper 50's are dropping the pool temp so any recovery is slow. Hoping a little help from my home-built will have us swimming in the evenings/weekends.
TomC

[towney]

I don't know much about heat pumps--just a little. Pool heating is an ideal application--the outside air is warm (in heat pump terms--in the 50's or higher) so they get into their super-efficient range, far more so than gas.

H/Ps have a bad rep because they were used for heating and cooling houses in Northern Virginia (near DC) where it's far too cold for them to be efficient in the winter. But for pools they are supposed to be terrific.

They are expensive to install--2 to 3x what a gas heater costs, but far more efficient. If you need to heat a pool fast, though, they aren't so good--gas is better. But keeping it warm? I gather they can't be beat.

Are they better than solar? In some ways yes, in some ways no.

If you can do both, it would be great. You are in Florida, though, where you get lots and lots of sun.

Thanks gain CarlID
If this is of any help I do have a Starite 400K propane heater so I could use this in conjuction with either. But I still at an impass on which one.

[tphaggerty]

Solar should not get so hot that you can't use flex, BUT, there is no way you can tie that into your normal pump system, you would have to have a separate return to the pool (I think Poconos does it this way, he has a return running on the deck under his diving board just for solar - excuse me in advance if I'm wrong! Someone is doing it this way). Generally, an efficient solar system will return water that is no more than 5 degrees or so above the current pool temp.

[CarlD]

I use separate returns for my solar panels. In fact I have mine as two independent systems, each with its own return.

[Poconos]

That's me...separate return hoses dumping into the deep end and running under the diving board to keep them out of the way. I tie a bleach bottle loaded with sand to the ends to keep the hose ends deep.
Al

[brent.roberts]

Here is a link that has all the unbiased information you need to make a good decision. It is the Florida State University of Central Florida .

http://www.fsec.ucf.edu/solar/install/poolinst/poolinst.htm

It has sections for other solar applications as well as pools.

I find the navigation around the site very UN-intuititve. You'll have to work at finding the good stuff.
For example you'll need to do a lot of mining to find this page,

http://www.fsec.ucf.edu/solar/testcert/collectr/tprpoolap.htm

which is half of the efficiency testing of panels for pools, this is makers A to P. Q to Z is nearby. ( they do have another for domestic hot water heaters )

The rule of thumb seems to be
1) the cheapest panels have the least amount of plastic and are the least durable and the poorest investment
2) they ( the cheapest) seem to rate pretty high on the efficiency test because they have thin walls, but are again not the best investment.

I selected Techno-solis using this guide. Our home lot is on a hill with the pool just about at the top, so a south facing slope became a great site for the panels. They are literally just thrown on the ground and connected to the plumbing. The dogs chase the rabbits across them. I walk on them. Snow sits on them all winter. Absolutely no problems.

Anyway, read up and you'll make get what you need.

[TMan]

Thanks TP and Brent. Are you saying you can't tie the solar output into the return line to the pool? Surely it's done all the time, right? Isn't that what the T and 3-way valves shown in the 'easy installation' guides show? What am I missing? Hope to have a lot done by tomorrow on my setup. I'll post pics and obviously, data. Output temp, pool temp..etc. Thanks for all the ideas and links.

[tphaggerty]

Are you saying you can't tie the solar output into the return line to the pool? Surely it's done all the time, right? Isn't that what the T and 3-way valves shown in the 'easy installation' guides show? What am I missing?

It all depends on the type of panels and tubing. AG pools use the spiral flex type hose (looks like a vacuum cleaner hose or an IG vacuum hose) all the time. These are rated for fairly low pressure (they are generally joined by metal band clamps).

What I was saying is that if you have that type of return hose on the panels, you cannot join that to a permanent return that uses schedule 40 or flex PVC because the pressure will blow that line up. If you use that type of panel, just make sure the return goes directly to the pool (for an IG). For AG, you can T it in to the return (you will need the special barb type fittings)

For IG installations, the source and return lines for the panels are pressure rated, just like the rest of the plumbing. They need to be able to handle the 30+ psi that an IG pool pump will product. As in my case, the solar is pumped in AFTER the filter, but before my SWG (you want clean water, but not high chlorine). Hope this helps.

[TMan]

Thx TP, I have an AG but I'm plumbing it with schd. 40 anyway, and will T it in, almost finished. Another issue, I'm using a SWG too and want to plumb it in Before the solar heater, not after. This is because the model I have reduces chlorine output when the water gets warm, anything above 90-degrees for mine and the 'check cell' light starts flashing. I expect the heated return water to be well above that. Then it will not be generating at optimum meaning more run time during the evening/morning, cooling off the pool and then I'm going backwards. It'a a Goldline AquaTrol for AG pools and works well, within a range. What do you think of running the chlorinated water thru the solar heaters? I'm guessing that now it's hotter, chlorinated water being returned to the pool.

[CarlD]

Thx TP, I have an AG but I'm plumbing it with schd. 40 anyway, and will T it in, almost finished. Another issue, I'm using a SWG too and want to plumb it in Before the solar heater, not after. This is because the model I have reduces chlorine output when the water gets warm, anything above 90-degrees for mine and the 'check cell' light starts flashing. I expect the heated return water to be well above that. Then it will not be generating at optimum meaning more run time during the evening/morning, cooling off the pool and then I'm going backwards. It'a a Goldline AquaTrol for AG pools and works well, within a range. What do you think of running the chlorinated water thru the solar heaters? I'm guessing that now it's hotter, chlorinated water being returned to the pool.

Using sched 40 and running chlorinated water through your solar panels is no problem. I do both.

I have separate returns for my solar panels. The pool manufacturer, Fanta-Sea does it that way--but they put the solar return near the main return. Since the main is high pressure and the solar return is low pressure I don't see how you could easily combine them and it's very easy to plumb separate ones (unless you have a concrete pool).

When I modified the Fanta-Sea system to split the panels into two groups, I added two returns at the far end of the pool. The two returns allowed me to run higher pressure (and therefore about a 40% increase in flow) through the panels, meaning my water warms faster--the system is more efficient. I cut the returns in during the off-season when I had lowered the water, using a hole-saw of the correct size. It was a fairly easy job. The old solar return I converted into an over-flow by having the hose that came out of it go up first to maximum desired level before going down to a french drain.