Smart ways to heat your swimming pool year-round

Whilst swimming pools in the UK get plenty of use in the summer, especially when heatwaves come around, they’re often neglected in the winter, which needn’t be the case.

Learning how to heat a swimming pool efficiently means it can be used comfortably all year round, which not only means more fun and exercise, but a better overall return on investment.

Whether you’re a homeowner wanting to extend your season or a commercial operator looking to maximise facility appeal, there are several excellent options available. Solar heating systems, air source heat pumps, and ground source heat pumps all offer long-term benefits for pools of any size, as well as reducing your carbon footprint. We’ll explore each in more detail below.

At Signature Pools, we’ve spent over 15 years helping homeowners and commercial operators across the South West discover the perfect heating solution for their needs. In this guide, we’ll walk you through the main methods of pool heating, their costs, and which option might be right for you.

How to heat a swimming pool

For both domestic and commercial swimming pools of all sizes, there are several proven methods to keep your pool water at a comfortable temperature year-round. These solutions are best viewed as long-term investments that through time, pay dividends through lower running costs and extended swimming seasons.

The main approaches are solar heating systems and heat pumps (air source and ground source). Each has distinct advantages depending on your pool type, location and budget.

Our range is chosen to combine performance with energy efficiency. Whilst traditional gas heaters have been the go-to choice in years gone by, they are expensive to run and rely heavily on dwindling fossil fuels, something we wouldn’t necessarily recommend if you’re viewing a pool as a long-term investment. Instead, we’ve tested the sustainable alternatives, those mentioned below, intensely, and find that they match gas heaters for performance, without the higher running costs or substantial carbon footprint.

Solar heating systems

Solar pool heating harnesses the free energy of the sun to warm your pool water naturally. Systems typically consist of solar collectors (often solar panels mounted on your roof or ground), a circulation pump and a control system. Water is pumped through the solar collectors, where it’s heated by direct sunlight, then returned to your pool.

Solar heating shines in warmer climates with consistent sunshine. In the UK, solar systems work best during late spring, summer and early autumn, often extending your swimming season by several weeks either side of peak summer.

Advantages include:

–          Minimal running costs once installed

–          Free energy from the sun

–          Lower carbon footprint

–          Very little maintenance is required

–          Ideal for outdoor pools

–          Can be combined with other heating methods

Air source heat pumps

Air source heat pumps extract heat from the outside air and transfer it into your pool water through a heat exchanger. To emphasise their productivity, they deliver up to five times the electrical energy you put in as heat output. This exceptional efficiency makes them one of the cheapest ways to heat a swimming pool.

Advantages include:

–          Great seasonal efficiency, they’re brilliant during the peak months of summer

–          An environmental pick as they utilise free environmental energy

–          Adaptable scheduling, they only require around four hours of daily runtime in mild weather to maintain a comfortable temperature

–          Much cheaper to run than traditional fossil fuel alternatives

Ground source heat pumps

Ground source heat pumps tap into naturally stored heat beneath the ground. Underground temperatures remain stable year-round, typically between 10-13°C, making them exceptionally reliable. The system circulates fluid through underground pipes (buried 1.5 to 2.5 metres deep), capturing thermal energy and transferring it to your pool water.

Ground source systems offer outstanding long-term efficiency and lower running costs over time. What makes them particularly attractive for commercial pools is their consistency. Whether summer or winter, the ground temperature remains constant, meaning your heating system delivers reliable performance throughout the year without seasonal variations.

At Signature Pools, we specialise in ground source heat pump installation for both residential and commercial applications. These systems work beautifully for larger pools where the return on investment justifies higher upfront costs.

Advantages include:

–          The best pick for consistent year-round performance

–          Lower running costs than air source systems

–          Exceptional lifespan and durability

–          Discreet, quiet operation

–          Eco-friendly, low carbon

Comparison table: Heating options for swimming pools

Heating Method	Best Season	Key Advantage	System Ideal For
Air Source Heat Pump	Spring to Autumn	High energy efficiency during the primary swimming season.	Standard domestic outdoor pools looking for a balanced, eco-friendly setup.
Ground Source Heat Pump	Year-round	Exceptional, stable efficiency that is entirely unaffected by freezing air temperatures.	Larger residential or commercial pools requiring consistent, year-round operation.
Solar Heating System	Late Spring to Early Autumn	Completely sustainable operation that utilises free solar energy. Minimal running costs.	Outdoor pools seeking a natural temperature boost during the sunnier months.

Which option is best for my pool?

Choose solar heating if:

• Your pool is outdoors with good sun exposure
• Running costs are your biggest concern (solar is essentially free after installation, you just pay a minimal amount to keep the pump running)
• You’re willing to combine it with another heating method for winter months
• Environmental impact is your priority

Choose an air source heat pump if:

• You want affordable, efficient heating with low running costs
• You’re happy swimming mainly between March and October
• You have limited space for underground installation
• Your pool is residential or commercial, above-ground or in-ground

Choose a ground source heat pump if:

• You have available land space for underground loop installation
• You can afford the higher installation cost
• You want year-round consistent heating without seasonal variations
• You’re a commercial operator managing a larger pool facility
• Long-term sustainability and lowest possible running costs matter most

Commercial operators should consider:

• Hybrid systems combining heat pumps and solar for maximum efficiency
• Ground source heat pumps for larger pools requiring consistent year-round temperatures
• Systems that can be remotely monitored and controlled
• Long-term ROI calculations, as energy savings compound significantly

How much does it cost to heat a swimming pool?

It’s hard to give exact figures as this depends on a number of factors, including the size of the pool, so here is a broad outline instead. You can get in touch for more accurate estimates.

Solar Heating:

• Moderate upfront installation relative to the long-term energy savings achieved
• Running costs are minimal to none, requiring only basic electricity for the circulation pump
• Virtually zero annual cost impact, making it the most sustainable option on the market

Air Source Heat Pump Running Costs:

• Highly competitive per-hour operational costs compared to traditional fossil-fuel heating
• Economical monthly operating profile throughout the standard swimming season
• Predictable annual cost structure tailored for seasonal pool use

Ground Source Heat Pump Running Costs:

• Slightly lower per-hour running costs than air source systems due to stable underground energy
• Consistent monthly operating costs that remain stable regardless of the outdoor weather
• Higher initial installation cost than air source alternatives

Bonus tips to lower pool heating costs

Use a quality pool cover

A quality pool cover is one of the most underrated energy-saving tools.

Heat loss through the pool surface accounts for 75-80% of total energy loss, so a solid cover dramatically reduces evaporation and heat loss, meaning your heating system works less hard.

Maintain your heating system

Regular maintenance keeps your system running efficiently. For heat pumps, clear any debris from the outdoor unit and ensure proper airflow. For solar collectors, keeping panels clean maximises sun absorption. At Signature Pools, we offer comprehensive maintenance packages that keep your system in peak condition.

Maintain proper water chemistry

Balanced pool water allows your heating system to work more efficiently. If your water chemistry is unbalanced, the heating system will have to work a lot harder, which will naturally increase costs and negatively impact performance. To ensure this isn’t the case, we recommend regular testing and chemical adjustments where necessary.

Heated swimming pools from Signature Pools

At Signature Pools, we’re proud of our full service pool offering. From everything to the initial design, to our material and heating recommendations, to the installation and then aftercare, we’re a one-stop-shop for everything pool related.

We regularly work on both residential and commercial projects. It doesn’t matter if you’re looking for a smaller pool to fit inside a garden, or one to serve 200+ clients daily at a leisure centre, we’ve done it all before. Our commercial expertise covers hotels, holiday parks, fitness centres, leisure facilities, schools and specialist hydrotherapy pools, each with unique heating and climate control requirements.

We work with multiple materials and designs, including concrete, block liner, one-piece fibreglass and timber-effect pools, each available with integrated heating solutions. Our heating offerings include air source heat pumps, ground source heat pumps and solar heating systems, all selected for sustainability and long-term efficiency.

Beyond heating, we offer pool refurbishment, plant room repairs and leak detection services. As SPATA and BISHTA accredited specialists with membership in the Institute of Swimming Pool Engineers, we maintain the highest industry standards.

Who are Signature Pools?

We’re a family-run business established in 2008, serving customers throughout the South West of England including Devon, Cornwall, Somerset, Dorset and Bristol. With over 15 years’ experience, we’re a trusted provider of high-quality pool, spa and leisure solutions for both commercial and residential clients.

Our commitment to sustainability runs through everything we do. We source eco-friendly products from our suppliers and educate clients on energy-efficient options to reduce energy consumption and environmental impact. We’ve received numerous awards, including LABC Building Excellence Regional Winner 2020, and maintain accreditations with SPATA, BISHTA and the Institute of Swimming Pool Engineers.

Ready to extend your swimming season and reduce energy bills? Get in touch with Signature Pools today.

Contact us:

• Phone: 01626 333414
• Email: info@signaturepoolsuk.com
• Address: Unit 6 Aller Vale Buildings, Moor Park Road, Kingskerswell, Newton Abbot, Devon, TQ12 5AZ

FAQs: Swimming Pool Heating

Q: What’s the best pool heater for my size of pool?

A: Pool size is a good way to determine your heating selection. For instance, smaller pools typically suit solar pool heaters, whereas larger pools benefit from electric pumps, like ground source heat pumps, that deliver faster heating and consistent desired water temperature control.

Q: How do pool heat pumps perform in colder climates?

A: Electric heat pumps extract heat from ambient air, or the ground, effectively until temperatures drop significantly. In very cold climates, hybrid systems combining heat pumps with supplementary heating ensure comfortable water temperature year-round.