Swimming pools are big energy consumers. Pool owner/operators spend billions of dollars annually to heat the world's pools. Much of this energy is often wasted and can be saved with proper management. Wasting energy also contributes to our growing air quality problem.
Most swimming pools require some type of heating, whether to bring the pool up to temperature in the spring, to maintain a desired temperature during the swimming season, or to extend the swimming season. You can use conventional gas or electric heaters, but you may have large monthly bills from your local utility company.
Another option is to install a heating system that captures the free heat of the sun. Solar energy is a renewable domestic fuel that's widely available. Today, solar pool heating systems can be cost competitive with conventional heaters. Their advantage...very low operating costs.
Solar pool heating uses lower cost collectors and low water temperatures making it a cost-effective use of solar energy.
The simplest solar collector is a black hose lying in the sun that you can circulate water through. The sun shines on the black hose and heats up the water flowing through it. This is not a very efficient or durable solar collector, however.
To increase the efficiency of collecting solar heat, solar collector manufacturers have designed several types of solar collectors that maximize the amount of solar energy collected and are designed to last 15-20 years.
Most solar collectors are flat sheets, called absorber plates, with tubes running from bottom to top. Headers at the top and bottom supply the fluid to be heated. Some have a glazing over the top of the collector that aids in preventing the wind and cold air from carrying away the heat before it can get to its destination, but this greatly increases the cost of the collector..
Solar collectors are made of a variety of materials. Collectors that operate only when temperatures are above freezing can be made of lower cost materials such as thermoplastic rubber or polypropylene. These collectors can be used in the far southern part of the U.S. and for all outdoor seasonal use pools in the rest of the U.S.
Collectors that operate in colder climates on a year around basis generally have copper absorber plates with low iron tempered glass as a covering. This allows the collector to maintain most of its efficiency even during the cold winter months. As long as the sun is shining, it will collect some solar heat. But these collector systems require transfer fluid and heat exchangers which increase the total system cost.
Solar Heating Systems
Solar collectors are only one part of a total solar pool heating system. A simple unglazed pool heating system includes the pool pump and two heat sensors connected to a solar controller. One sensor measures the temperature at the collector surface. The other measures the pool temperature. If the difference between the two is sufficient, the controller sends a signal to a motorized valve that closes and directs the pool water through the solar collectors.
All the water circulated by the filter pump will pass through the solar system. Each time the water passes through the solar collectors it is heated 2-5 degrees. A properly sized solar system can raise the pool temperature 10-20 degrees and maintain a comfortable swimming temperature.
The purpose of solar heating a pool is usually to provide a comfortable and enjoyable pool water temperature during mild weather. Under these conditions, systems with open absorber plate solar collectors are most efficient and cost effective. These unglazed systems can even work for indoor pools in cold climates if the system is designed to drain back to the pool when not in use. Even if you have to shut the system down during cold weather, it may be more cost effective than installing a more expensive glazed collector system.
Glazed collectors systems can also be used to heat pools. Due to the ability of the glazing to trap heat and by using copper absorber plates, heat exchangers and transfer fluids, these systems can collect large amounts of solar heat even in the coldest weather. However, glazed solar systems often cost several times as much as unglazed systems. Another advantage of glazed systems is that they can double to heat domestic hot water year around.
A modern pump, properly sized for filtration and skimmer action will almost always be adequate for a solar system. The extra lift to the roof is balanced by the return head in a closed system. If the pump isn't large enough, a booster pump will have to be added.
There are a number of things to consider when trying to determine if a solar pool heating system is right for your pool.
Is there a large, sunny roof or open area available for mounting several hundred square feet of solar collector? Does the area have unobstructed sunlight from 8:00 am to 4:00 pm during the heating season or even later in the day for mid-summer use? Is it possible to securely anchor the collectors on the selected area? (The solar collectors can be mounted on a roof, on a deck, on a rack, or on the ground).
Also, the system should be installed in accordance with all local building and zoning requirements.
Orientation and Tilt
Ideally, collectors should face due south in the northern hemisphere and due north in the southern hemisphere. However, they can usually be oriented within 15 east or west of south with little loss in performance. Some sources even say up to a 45 variation is OK, but you will lose some performance.
The ideal collector angle varies based on latitude, and whether you need the heat in the summer months, during the winter months, or you need the heat all year around.
For summer only heating, use latitude minus 10-15. For winter only heating, use latitude plus 10-15. For year around heating, install the collectors at latitude. Variations from these ideals can be compensated for by adding additional collector area.
Solar pool heating systems can be installed to provide up to 100% of your pool heating needs. The size of the system depends on available solar insolation, wind factors, average temperatures for the region, and collector orientation and angle. Contact your local supplier for a proper sizing calculation.
It is a good idea to make your pool as efficient as possible before considering a solar pool heating system. The easiest way to lower your pool heating costs is to use a pool cover that stops evaporation when the pool is not in use.
By reducing your pool heating needs prior to the purchase of a solar pool heating system, you can purchase a smaller system, saving money.
If inconvenience or aesthetics is a major concern that keeps you from using a pool cover, then a solar pool heating system can provide you with low cost heat without affecting the looks of the pool.
Using solar energy to heat swimming pools is one of the best use of solar collection devices. Solar systems have become so easy to install that many pool owners can do it themselves. But, if you want a professionally installed system, contact a local solar dealer that has experience in solar heating swimming pools.
Bwawa la kuogelea hutumia nishati nyingi. Wamiliki wa mabwawa hutumia mabilioni ya dola kila mwaka kupasha maji mabwawa ya ulimwengu. Mara nyingi nishati hiyo nyingi hutumiwa bure na inaweza kuokolewa kwa njia inayofaa. Kutumia nishati bure pia huchangia tatizo letu la kuongezeka kwa ubora wa hewa. Hifadhi nyingi za kuogelea zinahitaji aina fulani ya joto, iwe ni kuleta dimbwi hadi joto katika majira ya kuchipua, kudumisha joto linalotakiwa wakati wa msimu wa kuogelea, au kupanua msimu wa kuogelea. Unaweza kutumia vifaa vya kawaida vya kupasha joto vya gesi au umeme, lakini huenda ukapata bili kubwa za kila mwezi kutoka kwa kampuni yako ya huduma za umma. Njia nyingine ni kuweka mfumo wa kupasha joto ambao huchukua joto la jua. Nishati ya jua ni nishati ya ndani inayobadilika ambayo inapatikana sana. Leo, mifumo ya joto ya bwawa ya jua inaweza kuwa na gharama ya ushindani na vifaa vya joto vya kawaida. Faida yao...gharama za chini sana za uendeshaji. Joto la jua la kupasha maji maji huchukua vifaa vya chini na joto la chini la maji, na hivyo kufanya matumizi ya nishati ya jua yawe ya gharama nafuu. Solar collector ni mfereji mweusi wa maji unaotumiwa kuingiza maji. Jua huangaza kwenye mfereji mweusi na kupasha joto maji yanayotiririka ndani yake. Hata hivyo, hii si mkusanyaji wa jua mwenye ufanisi sana au wenye kudumu. Ili kuongeza ufanisi wa kukusanya joto la jua, wazalishaji wa mkusanyaji wa jua wamebuni aina kadhaa za mkusanyaji wa jua ambao huongeza kiasi cha nishati ya jua inayokusanywa na imeundwa kudumu miaka 15-20. Vichukizo vingi vya jua ni karatasi tambarare, zinazoitwa sahani za kunyonya, zenye mirija inayoanzia chini hadi juu. Vichwa vya juu na vya chini hutoa kioevu kinachopashwa joto. Baadhi ya vifaa hivyo vina kioo juu ya mkusanyaji, ambacho huzuia upepo na hewa baridi usichukue joto kabla ya kufika mahali pake, lakini hii huongeza sana gharama ya mkusanyaji. Vipuli vya jua hutengenezwa kwa vifaa mbalimbali. Vichukizo vinavyofanya kazi tu wakati joto ni juu ya kuzima vinaweza kutengenezwa kwa vifaa vya gharama nafuu kama vile mpira wa thermoplastic au polypropylene. Kwa ujumla, collectors kutumika katika sehemu ya kusini ya mbali ya Marekani na kwa ajili ya wote nje msimu matumizi ya mabwawa katika sehemu nyingine ya Marekani. collectors kwamba kazi katika hali ya hewa baridi zaidi juu ya mwaka kuzunguka msingi kwa ujumla kuwa na shaba absorbers sahani na chini chuma tempered kioo kama kifuniko. Hilo huruhusu mkusanyaji kudumisha ufanisi wake hata wakati wa miezi ya baridi kali ya majira ya baridi kali. Maadamu jua linaangaza, litachanganya joto fulani la jua. Lakini mifumo hii ya mkusanyaji inahitaji uhamisho wa kioevu na exchangers joto ambayo kuongeza jumla ya gharama ya mfumo. Solar Heating Systems Solar collectors ni sehemu moja tu ya jumla ya mfumo wa joto pool jua. Mfumo rahisi unglazed pool joto ni pamoja na bwawa pampu na sensorer mbili joto kushikamana na mtawala wa jua. Sensorer moja hupima joto kwenye uso wa mkusanyaji. Nyingine hupima halijoto ya dimbwi. Ikiwa tofauti kati ya mbili ni ya kutosha, udhibiti hutuma ishara kwa valve motorized ambayo hufunga na inaelekeza maji ya dimbwi kupitia collectors jua. Maji yote yanayotiririka na pampu ya kichujio yatapita kupitia mfumo wa jua. Kila wakati maji hupita kupitia collectors jua ni joto digrii 2-5 Kwa mfano, mfumo wa jua wa ukubwa sahihi unaweza kuongeza joto la dimbwi kwa digrii 10-20 na kudumisha joto la kuogelea. Kusudi la kupasha joto la jua kwenye dimbwi kwa kawaida ni kutoa joto la maji la dimbwi lenye starehe na lenye kufurahisha wakati wa hali ya hewa ya kiasi. Chini ya hali hizi, mifumo na wazi absorber sahani solar collectors ni ufanisi zaidi na gharama nafuu. Mifumo hii unglazed inaweza hata kufanya kazi kwa ajili ya mabwawa ya ndani katika hali ya hewa baridi kama mfumo ni iliyoundwa kwa drain nyuma ya bwawa wakati si katika matumizi. Hata kama unahitaji kuzima mfumo wakati wa hali ya hewa baridi, inaweza kuwa na gharama nafuu zaidi kuliko kufunga gharama kubwa zaidi glazed mfumo wa mkusanyaji. Mifumo ya collectors glazed pia inaweza kutumika joto mabwawa. Kwa sababu ya uwezo wa kioo cha kuhifadhi joto na kwa kutumia sahani za absorber za shaba, exchangers za joto na maji ya uhamisho, mifumo hii inaweza kukusanya kiasi kikubwa cha joto la jua hata katika hali ya hewa ya baridi. Hata hivyo, mara nyingi mifumo ya jua yenye kioo hugharimu mara kadhaa kuliko mifumo isiyo na kioo. Faida nyingine ya mifumo yenye kioo ni kwamba inaweza kutumiwa mara mbili kupasha maji moto ya nyumbani mwaka mzima. Pampu ya kisasa, yenye ukubwa unaofaa kwa ajili ya uchujaji na skimmer hatua itakuwa karibu daima kuwa ya kutosha kwa ajili ya mfumo wa jua. Lift ziada kwa paa ni usawa na kichwa kurudi katika mfumo uliofungwa. Kama pampu si kubwa ya kutosha, pampu booster itabidi kuongezwa. Kuna mambo kadhaa ya kuzingatia wakati wa kujaribu kuamua kama mfumo wa joto la jua la dimbwi ni sahihi kwa dimbwi lako. Je, kuna paa kubwa lenye jua au eneo la wazi linalopatikana kwa ajili ya kuweka mita mia kadhaa za mraba za mchanganyiko wa jua? Je, eneo hilo lina mwanga wa jua bila vizuizi kutoka 8:00 asubuhi hadi 4:00 jioni wakati wa msimu wa joto au hata baadaye katika siku kwa ajili ya matumizi ya katikati ya majira ya joto? Je, inawezekana kwa usalama anchor collectors juu ya eneo lililochaguliwa? (Vipuli vya jua vinaweza kuwekwa kwenye paa, juu ya sakafu, juu ya rafu, au ardhini). Pia, mfumo huo unapaswa kuwekwa kulingana na mahitaji yote ya ujenzi na ugawaji wa maeneo. Mwelekeo na Mwelekeo Kwa kawaida, wakusanyaji wanapaswa kukabili upande wa kusini katika kizio cha kaskazini na upande wa kaskazini katika kizo cha kusini. Hata hivyo, kwa kawaida wanaweza kuwa oriented ndani ya 15 mashariki au magharibi ya kusini na kupoteza kidogo katika utendaji. Kwa mfano, kuna uwezekano wa kuwa na kiwango cha juu cha 45%, lakini kwa kweli, unaweza kupoteza utendaji. Kwa mfano, pembe ya mkusanyiko wa joto inatofautiana kulingana na latitudo, na ikiwa unahitaji joto katika miezi ya majira ya joto, wakati wa miezi ya majira ya baridi, au unahitaji joto mwaka mzima. Kwa joto la majira ya joto tu, tumia latitudo minus 10-15. Kwa ajili ya joto majira ya baridi tu, kutumia latitude pamoja na 10-15. Kwa mwaka kuzunguka joto, kufunga collectors katika latitude. Tofauti kutoka kwa mawazo haya inaweza kusawazishwa kwa kuongeza eneo la mkusanyaji wa ziada. Mfumo wa joto wa jua wa kuogelea unaweza kuunganishwa ili kutoa hadi 100% ya mahitaji yako ya joto la kuogelea. Ukubwa wa mfumo hutegemea insolation ya jua inayopatikana, mambo ya upepo, joto la wastani kwa mkoa, na mwelekeo wa mkusanyaji na pembe. Wasiliana na muuzaji wako wa mahali hapo kwa ajili ya hesabu sahihi ya ukubwa. Ni bora kufanya pool yako iwe na ufanisi iwezekanavyo kabla ya kuzingatia mfumo wa joto wa jua. Njia rahisi ya kupunguza gharama za kupasha maji ya bwawa ni kutumia kifuniko cha bwawa ambacho kinazuia mvuke wakati bwawa halitumiwi. Kwa kupunguza mahitaji yako ya joto la dimbwi kabla ya kununua mfumo wa joto wa dimbwi la jua, unaweza kununua mfumo mdogo, kuokoa pesa. Ikiwa usumbufu au aesthetics ni wasiwasi mkubwa ambao unakuzuia kutumia kifuniko cha dimbwi, basi mfumo wa joto wa dimbwi la jua unaweza kukupa joto la gharama nafuu bila kuathiri sura ya dimbwi. Kutumia nishati ya jua kupasha joto vidimbwi vya kuogelea ni mojawapo ya njia bora zaidi za kutumia vifaa vya kukusanya nishati ya jua. Mifumo ya jua imekuwa rahisi sana kuanzisha hivi kwamba wamiliki wengi wa mabwawa wanaweza kufanya hivyo wenyewe. Ikiwa unataka mfumo wa kupasha joto wa jua, wasiliana na muuzaji wa jua wa karibu ambaye ana uzoefu katika kupasha joto la jua kwenye mabwawa ya kuogelea.