Pool Heater Types Compared: Gas, Solar, and Heat Pump

Pool heater types break down into three main categories: gas, solar, and heat pump. Each one has a completely different cost structure, a completely different usage pattern, and a completely different best-fit scenario. This guide walks through all three with honest 2026 pricing and helps you work out which one makes sense for an Adelaide backyard pool.

Gas pool heaters

Gas heaters burn natural gas or LPG to warm pool water directly via a heat exchanger. They heat fast and strong — from cold to swimming temperature in a matter of hours — and can hit any target temperature regardless of weather.

How they work

A gas burner heats a finned copper or cupronickel heat exchanger. Pool water pumped through the exchanger absorbs the heat and returns warm to the pool. Temperature is controlled by thermostat cycling the burner on and off.

Pros

• Fast heating — useful for on-demand or occasional heating
• Hits any target temperature in any weather
• Cheaper upfront than heat pumps
• Reliable and well-understood technology

Cons

• Running costs are very high: $15 to $25+ per day of active heating
• Requires natural gas connection or LPG bottle supply
• Annual servicing recommended
• Emissions and environmental footprint

Cost 2026

• Unit and install: $3,500 to $8,000
• Running cost: $15 to $30 per day of active heating
• Annual service: $200 to $350

Best for

Occasional heating — a pool party, a cold snap, bringing the pool up for a weekend. Not practical for full-season heating because running costs get ugly fast.

Heat pump pool heaters

Heat pumps extract heat from ambient air and transfer it into the pool water using refrigeration cycle technology. They’re the same physics as a reverse-cycle air conditioner, just tuned for water heating.

How they work

Refrigerant absorbs heat from outside air, gets compressed (which concentrates the heat), and then transfers that heat to pool water through a heat exchanger. Running costs are far lower than gas because the heat pump is moving heat rather than creating it.

Pros

• Very efficient — delivers 4 to 6 units of heat per unit of electricity
• Running costs roughly 30% of gas
• No gas supply required
• Can extend swimming season to nearly year-round in Adelaide

Cons

• Slower heat-up than gas (days rather than hours)
• Efficiency drops in very cold weather
• Higher upfront cost than gas
• Unit is physically large and needs clearance

Cost 2026

• Unit and install: $5,000 to $10,000
• Running cost: $5 to $12 per day of active heating

Best for

Season extension and regular use. If you want to swim October through April comfortably, and May and September on warm days, a heat pump is the right call.

Solar pool heaters

Solar pool heating circulates pool water through collector panels (usually on the roof) where sunlight warms the water before returning it to the pool.

How they work

A controller monitors pool water temperature and roof temperature. When the roof is hotter than the pool, the circulation pump pushes pool water through the collectors. Solar-warmed water returns to the pool until the target temperature is reached.

Pros

• Zero running costs (beyond the small circulation pump)
• Environmentally friendly
• Can provide meaningful heating October through April in Adelaide
• Long lifespan on quality systems (20+ years)

Cons

• Weather-dependent — doesn’t work on cold, cloudy days
• Requires suitable roof area and orientation
• Can be slow to raise pool temperature during cool weather
• Not suitable as sole heater if you want consistent winter swimming

Cost 2026

• Unit and install: $4,000 to $9,000 depending on pool size and roof complexity
• Running cost: Near zero (minimal pump power)

Best for

Owners who want extended season at minimal running cost and don’t need a guaranteed temperature on demand.

Combining heater types

A common approach is combining solar with a small gas booster or heat pump. Solar does the bulk of the heating in mild weather, and the gas or heat pump adds a boost for cold snaps or evenings. This gives the cheapest running cost with the flexibility of on-demand heating.

What pool heater type makes sense for your Adelaide pool

Scenario 1: Occasional use only

If you heat the pool a handful of times a year for special occasions, gas heating is cheapest overall because you don’t use it enough for running costs to matter, and upfront cost is lowest.

Scenario 2: Season extension

Swimming October to April with the occasional cold snap — heat pump is the best call. Running costs are manageable and upfront pays back in 4 to 6 years of active use.

Scenario 3: Every day use

Families with kids who swim daily in warmer months should consider solar for bulk heating with a small gas booster for overnight top-up. Lowest running cost, widest comfort window.

Scenario 4: Year-round pool

Realistic year-round swimming in Adelaide needs a heat pump (or a large gas system) plus a quality pool cover. Without a cover, running costs become impractical.

Pool cover: the other half of heating cost

A pool cover reduces heat loss by 50% to 80%. Any heater decision should include a pool cover — without one, you’re pouring heat into the atmosphere every night. Blanket covers are cheapest, roller covers are easier, and automatic covers are most convenient.

Read our summer preparation guide for timing heater maintenance, or our pool maintenance guide for broader care context.

Our pool equipment service covers heater supply and installation alongside pump, filter and chlorinator work. For resurfacing pricing, see the cost guide or cost estimator.

Thinking about pool heating for the first time or replacing an old system? Contact us or call 1800 724 683. We’ll help you match the right heater to your usage, pool size and budget.