Pool swim season in Casa Grande, AZ
Casa Grande, AZ: how long the pool season really is
An unheated pool in Casa Grande reaches 78°F in May to Oct, about 6 months a year. The air allows up to 10 swimmable months with a heater (Feb to Nov).
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Heater options for a Casa Grande pool, side by side
| Option | Months | Swimmable | Energy/yr | All-in/yr |
|---|---|---|---|---|
| No heater | 6 | May to Oct | $0 | $0 |
| Solar cover only | 6 | May to Oct | $0 | $50 |
| Solar panels + cover | 9 | Mar to Nov | $0 | $283 |
| Heat pump + cover | 10 | Feb to Nov | $339 | $889 |
| Gas heater + cover | 10 | Feb to Nov | $771 | $1,196 |
For a 450 sq ft pool held at 80°F, at AZ prices of 15.4¢/kWh electricity and $19/Mcf gas. All-in spreads the purchase over the equipment's life.
The cheapest way to the full season in Casa Grande
Solar panels + cover: 9 of 10 possible months for about $283 a year all-in, which works out near $94 for each month it adds.
A solar cover alone adds no swim months here, so if you want a longer season you need a heater (why); still use one at night to hold the heat you pay for. If you get quotes, ask for a heat pump sized to your pool's surface area; here it beats gas all-in (heat pump or gas).
Weather station: Casa Grande, 3.1 mi away (NOAA 1991–2020 normals). Water temperature is estimated from air and sunshine, not measured.
Casa Grande month by month: air, sun and pool water
| Month | Air high | Air avg | Sun kWh/m²/day | Water, unheated | Water, covered | Heat pump $ | Gas $ |
|---|---|---|---|---|---|---|---|
| Jan | 69° | 54° | 3.6 | 54° | 60° | – | – |
| Feb | 73° | 57° | 4.6 | 57° | 63° | $169 | $366 |
| Mar | 80° | 64° | 6.0 | 63° | 69° | $97 | $230 |
| Apr | 88° | 70° | 7.4 | 71° | 77° | $22 | $57 |
| May | 96° | 78° | 8.2 | 80° | 86° | – | – |
| Jun | 106° | 88° | 8.4 | 89° | 95° | – | – |
| Jul | 107° | 93° | 7.2 | 94° | 100° | – | – |
| Aug | 105° | 91° | 6.7 | 96° | 102° | – | – |
| Sep | 100° | 86° | 6.1 | 92° | 98° | – | – |
| Oct | 91° | 74° | 5.1 | 82° | 88° | – | – |
| Nov | 78° | 61° | 3.9 | 69° | 75° | $51 | $118 |
| Dec | 68° | 53° | 3.2 | 57° | 63° | – | – |
Heating costs most in Feb (about $169 with a heat pump, $366 with gas). Sunshine peaks in Jun at 8.4 kWh/m²/day (NASA satellite data, 51.5 km grid cell). Highlighted months are swimmable with no heater.
How Casa Grande compares with nearby cities
Casa Grande ranks 15 of 44 Arizona cities for unheated swim months, and no nearby city gets a longer unheated season.
| City | Distance | Unheated months | Heat pump months | Heat pump $/yr |
|---|---|---|---|---|
| Coolidge, AZ | 14 mi | 6 | 10 | $397 |
| Eloy, AZ | 15 mi | 6 | 11 | $625 |
| Maricopa, AZ | 17 mi | 6 | 10 | $384 |
| Florence, AZ | 23 mi | 6 | 10 | $326 |
| Queen Creek, AZ | 25 mi | 6 | 9 | $206 |
| Chandler, AZ | 26 mi | 6 | 11 | $550 |