Gas Heaters
Fastest heating (1-2°F per hour). Cost: $2,500-$5,000 installed. Operating cost: $200-$600/month depending on usage. Best for: spa heating, occasional pool heating, cold climates where heat pumps struggle.
Heat Pumps
Most efficient option - extract heat from ambient air. Cost: $3,000-$6,000 installed. Operating cost: $50-$150/month. Slower heating (0.25-0.5°F per hour) but dramatically cheaper to run. Best for: year-round heating in climates above 50°F.
Solar Heating
Lowest operating cost (nearly free). Requires roof-mounted or ground-mounted collectors. Cost: $3,000-$7,000 installed. Extends pool season 2-4 months in most climates. Best for: environmentally conscious homeowners, sunny climates.
Combination Systems
Many pools use a heat pump for daily maintenance heating and a gas heater for rapid spa heating or cold-weather boosts. This combination maximizes efficiency while maintaining flexibility.
Pro Tip
A pool cover reduces heat loss by 50-70% and can cut heating costs nearly in half regardless of heating method.