Pool swim season in Clemson, SC
Swim season in Clemson without a heater, and with one
An unheated pool in Clemson reaches 78°F in Jul to Aug, about 2 months a year. The air allows up to 7 swimmable months with a heater (Apr to Oct).
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Heater options for a Clemson pool, side by side
| Option | Months | Swimmable | Energy/yr | All-in/yr |
|---|---|---|---|---|
| No heater | 2 | Jul to Aug | $0 | $0 |
| Solar cover only | 4 | Jun to Sep | $0 | $50 |
| Solar panels + cover | 6 | May to Oct | $0 | $283 |
| Heat pump + cover | 7 | Apr to Oct | $246 | $796 |
| Gas heater + cover | 7 | Apr to Oct | $510 | $935 |
For a 450 sq ft pool held at 80°F, at SC prices of 15.9¢/kWh electricity and $17/Mcf gas. All-in spreads the purchase over the equipment's life.
The cheapest way to the full season in Clemson
Solar panels + cover: 6 of 7 possible months for about $283 a year all-in, which works out near $71 for each month it adds.
Before you pay for any heater, buy a solar cover: on its own it adds 2 months here for about $50 a year (why a cover comes first). 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: Clemson Univ, 1.8 mi away (NOAA 1991–2020 normals). Water temperature is estimated from air and sunshine, not measured.
Clemson 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 | 53° | 43° | 2.7 | 44° | 50° | – | – |
| Feb | 57° | 46° | 3.4 | 45° | 51° | – | – |
| Mar | 65° | 53° | 4.4 | 51° | 57° | – | – |
| Apr | 73° | 61° | 5.7 | 59° | 65° | $142 | $287 |
| May | 81° | 69° | 6.2 | 68° | 74° | $52 | $117 |
| Jun | 88° | 76° | 6.5 | 76° | 82° | – | – |
| Jul | 91° | 80° | 6.2 | 81° | 87° | – | – |
| Aug | 90° | 79° | 5.7 | 82° | 88° | – | – |
| Sep | 84° | 73° | 4.9 | 78° | 84° | – | – |
| Oct | 74° | 62° | 4.0 | 69° | 75° | $52 | $106 |
| Nov | 64° | 52° | 3.1 | 57° | 63° | – | – |
| Dec | 56° | 45° | 2.4 | 48° | 54° | – | – |
Heating costs most in Apr (about $142 with a heat pump, $287 with gas). Sunshine peaks in Jun at 6.5 kWh/m²/day (NASA satellite data, 35.0 km grid cell). Highlighted months are swimmable with no heater.
How Clemson compares with nearby cities
Clemson ranks 29 of 42 South Carolina cities for unheated swim months; Anderson nearby gets a longer season without a heater.
| City | Distance | Unheated months | Heat pump months | Heat pump $/yr |
|---|---|---|---|---|
| Anderson, SC | 15 mi | 3 | 7 | $231 |
| Easley, SC | 16 mi | 2 | 7 | $276 |
| Greenville, SC | 28 mi | 2 | 7 | $301 |
| Mauldin, SC | 29 mi | 2 | 7 | $301 |
| Simpsonville, SC | 32 mi | 2 | 7 | $275 |
| Fountain Inn, SC | 35 mi | 2 | 7 | $275 |