What It Costs to Heat a Pool in Florida

Pool heating cost is the product of three things, and a contractor who gives you a number without all three is guessing: how much heat your pool needs, how efficiently the heater converts fuel into that heat, and what you pay for the fuel. Change any one and the answer moves by hundreds of dollars a year.

The first depends on surface area, target temperature, how many months you heat, and whether the pool is covered, screened or exposed. The second is published by the manufacturer — a thermal efficiency percentage for a gas heater, a COP for a heat pump. The third is on your utility bill.

What this page does is show the arithmetic with current, sourced Florida energy prices, so you can redo it with your own rate and your own pool rather than trusting a number written for a different climate and a different electricity market.

All prices below are from the U.S. Energy Information Administration and were checked on September 17, 2026. Energy prices move; the method does not.

A million BTU is a convenient yardstick — roughly what it takes to raise a 15,000 gallon pool by 8°F — and it puts every fuel on the same basis. Using the prices above:

Electric heat pump at a COP of 5.0: one million BTU of heat is 293 kWh, and at a COP of 5.0 the compressor draws 58.6 kWh to move it — about $9.00 at 15.36 cents. At a COP of 6.0, which Florida's warm humid air supports for most of the year, it falls to about $7.50; at the 4.0 manufacturers publish for 50°F air it rises to about $11.25.

Natural gas at 84% thermal efficiency: one million BTU delivered needs 1.19 million BTU of gas, about 1.15 thousand cubic feet. At Florida's $25.48 average that is about $29 — subject to the caveat above, since a heavy user's real rate is usually better than the state average. Propane at the same efficiency needs about 13 gallons: roughly $46 at the East Coast residential price, or $35 at the U.S. average.

Electric resistance heating, for context, has no multiplier at all: 293 kWh at 15.36 cents is about $45 per million BTU, which is a useful reminder of what a heat pump's COP is actually buying you. Solar has no fuel cost at all — only the extra pump time needed to push water through the collectors, which for two extra hours a day of a 1 kW pump is about 60 kWh a month, roughly $9 at Florida's average rate.

The Department of Energy publishes annual pool heating cost estimates by city, and Miami is the closest Gulf Coast proxy in its table. Both DOE tables are built on a 1,000 square foot pool — more than twice a typical 15 by 30 foot residential pool — and both use energy prices that are now out of date, so the numbers below adjust for pool size and today's Florida prices with every step shown. Treat the result as an estimate, not a quote.

DOE's heat pump table (an air-to-water heat pump at an average COP of 5.0, electricity at 13.01 cents) puts a year-round Miami pool held at 80°F at $1,989 a year uncovered, and $409 a year with a cover. Scaling to a 450 square foot pool (multiply by 0.45, since the heating load is driven by surface area) and updating the electricity price (15.36 divided by 13.01, so multiply by 1.18) gives roughly $1,060 a year uncovered — about $88 a month averaged across the year — and roughly $215 a year, or $18 a month, with a cover.

DOE's gas table (an 80% efficient natural gas heater at $1.09 per therm) puts the same Miami pool at $3,880 a year uncovered and $796 with a cover. Scaling for the smaller pool and updating to Florida's $2.46 per therm — $25.48 per thousand cubic feet divided by 10.36 therms — gives roughly $3,900 a year, about $330 a month, uncovered, and roughly $800 a year, about $67 a month, with a cover. On propane at the East Coast residential price the same job is around 1.6 times the natural gas figure.

Two honest caveats. These are year-round figures for a pool held at 80°F every single day, and most Florida owners heat for part of the year, so a real bill is usually a fraction of this; and DOE's two tables make slightly different cover assumptions, so they are not perfectly parallel. What the comparison establishes reliably is the ratio: gas costs several times what a heat pump costs for the same heat, and a cover changes everything.

Roughly in order of impact, these decide your bill:

Solar is the only option here with no fuel cost, which makes it structurally different: you are buying the equipment, not the energy, and the running cost does not move when utility rates do.

The constraint is roof area. DOE's guidance is that collector area should equal 50-100% of the pool's surface area, and that a 15 by 30 foot pool in Florida typically needs collectors equal to 100% of the pool — about 450 square feet — for year-round use. If the available unshaded roof plane cannot take that, the system will underperform, which is why it gets measured before it gets quoted.

The pairing that works best on many Gulf Coast pools is solar carrying the load most of the year with a heat pump filling in cold mornings and cloudy weeks, so the heat pump runs a fraction of the hours it would alone.

To estimate your own cost you need four things: the pool's surface area, the temperature you want, the months you intend to heat, and the efficiency figure for the heater you are considering (thermal efficiency for gas, COP at both the 80°F and 50°F test points for a heat pump). Run those through the cost-per-million-BTU figures above with your own utility rate and you will land in a sensible range — which is all anybody can honestly promise before the pool is measured.

It is also worth pricing the cover first: a solar blanket is the cheapest thing on any quote we write, and on the DOE numbers it does more for the annual bill than any equipment upgrade.

If your pool is in Sarasota, Manatee, Charlotte & Pinellas County, we will look at the pool, the enclosure, the pad and your utility situation — including whether natural gas is available at your address at all — before recommending anything. The method here is written for pool owners anywhere; the site visit is local.