How Many Solar Panels Need To Run A Hot Tub?

Thinking about using solar panels to power your hot tub? You’re not alone. As energy prices climb and UK homeowners look for sustainable solutions, many are exploring how solar panels can offset the high running costs of hot tubs. 

But how many solar panels do you actually need to run one?

In this guide, we’ll break down the factors that influence solar panel requirements, show real-world examples, and help you make an informed investment decision. 

Whether you're a homeowner, landlord, or manage a commercial property, this article will give you everything you need to know.

How Many Solar Panels Are Needed To Power A Hot Tub In The UK?

You’ll typically need 2 to 7 solar panels to run a hot tub in the UK, depending on the size of the hot tub and how often it’s used. 

Smaller 2–3 person tubs may only require 2–3 panels, while larger 6+ person hot tubs used year-round could need 6 or more panels to run efficiently.

The number of solar panels required depends on the energy consumption of your hot tub and the energy output of your solar system. On average, UK hot tubs consume between 1.5 kWh and 7.5 kWh per day, depending on their size, insulation quality, and usage.

Typical Energy Consumption of Hot Tubs

According to Ofgem, the average UK solar panel (rated at 400W) produces approximately 1.1–1.3 kWh per day, depending on location and orientation.

Additionally, read our article on how much electricity a typical solar panel generates for deeper insights.

Quick Estimate: Number of Panels Needed by Hot Tub Size

These estimates are for solar PV panels only. Solar battery storage costs can add £3,000–£6,000 depending on capacity.

This assumes ideal conditions (south-facing roof, minimal shading, and good weather). To ensure year-round performance, especially in winter, it's wise to oversize your system by 20–30% since solar panel efficiency fluctuates based on placement and weather.

What Affects The Number of Solar Panels You’ll Need?

Several factors influence how many solar panels you need to run a hot tub efficiently:

1. Geographic Location in the UK

Solar energy output varies significantly by region. For instance:

If you're in Scotland or Northern England, you may need an extra panel or two to compensate for reduced sunlight.

2. Seasonality & Weather Conditions

UK winters are overcast and daylight hours are short. In December, solar production can drop by up to 80% compared to July. Therefore, hot tubs used year-round may require additional capacity, or even hybrid systems (solar + grid) to ensure consistent operation.

Do solar panels work on cloudy days is a common question, and while output is reduced, they still generate power.

3. Panel Placement, Angle, and Direction

• South-facing roofs with a 30–40° tilt offer the best year-round performance.
• East- or west-facing installations may lose up to 20% efficiency.
• can work well with adjustable mounting systems. Avoid shaded areas, especially during midday hours when solar production peaks. For more on maximising output, read our guide on horizontal vs vertical solar panel installation.

Avoid shaded areas, especially during midday hours when solar production peaks.

Is It Worth Using Solar Power for a Hot Tub in the UK?

Yes, it is worth using solar power for a hot tub, especially if:

• You already have or plan to install a solar PV system.
• You use your hot tub regularly (e.g. 3+ times per week).
• You want to reduce reliance on rising energy prices.

By using solar panels, you can offset running costs and lower your carbon footprint. Running a hot tub without solar can cost £30–£60/month, depending on energy tariffs. Over a year, that’s £360–£720 in potential savings.

According to the UK Government's Smart Export Guarantee (SEG), you can also sell unused electricity back to the grid.

Can Solar Batteries Help Run My Hot Tub More Efficiently?

Absolutely. Solar batteries allow you to store excess solar power generated during the day and use it later, for example, in the evening when you're more likely to use the hot tub.

On top of that, battery storage helps reduce grid reliance and can improve return on investment (ROI) from your solar setup.

Prices for solar batteries vary depend on the brand (e.g. Tesla Powerwall, GivEnergy, LG Chem), warranty, and integration complexity.

These prices include typical installation and VAT, based on current UK market rates as of mid-2025.

Should You Use Solar Thermal Panels Instead of PV Panels for a Hot Tub?

Solar PV panels convert sunlight into electricity, while solar thermal panels heat water directly. While thermal panels are highly efficient, they're less flexible and harder to integrate with modern electric-powered hot tubs.

For most homeowners, solar PV with optional battery storage is more versatile and scalable, especially if you plan to power other household appliances too.

How to Get the Best Solar Panel Quote for Your Hot Tub?

If you're considering powering your hot tub with solar energy, getting the right system tailored to your property is crucial. That's where Eco Answers comes in.

Use Eco Answers’ Quote Comparison Tool to connect with trusted UK solar panel suppliers. It’s quick, easy, and free to use.

Our free, easy-to-use tool connects you with trusted suppliers offering competitive quotes tailored to your needs. Just provide a few details, and we’ll match you with reputable providers.

FAQs 

Can I run a hot tub completely off-grid using solar panels?

Yes, but you’ll need a larger off-grid solar panel system with ample battery storage. Running off-grid requires careful system sizing to handle winter usage and backup power needs.

Can solar panels heat the water in the hot tub directly?

Not directly. Most hot tubs use electric heating elements. You can offset their electricity usage with PV panels, but not heat the water directly without specialised systems.

How long does it take to recoup the cost of solar panels for a hot tub?

Depending on usage and energy tariffs, most systems see ROI in 6–10 years, especially if you power other parts of your home too.

Is it possible to use portable solar panels for hot tubs?

Not recommended. Hot tubs require consistent energy output, which portable panels struggle to provide. Permanent roof-mounted systems are more reliable and efficient.

Do I need planning permission to install solar panels for a hot tub?

In most cases, no. Solar panel installations fall under permitted development rights, but exceptions apply in conservation areas or listed buildings. 

Conclusion

If you're wondering how many solar panels you need to run a hot tub in the UK, the answer depends on your tub's size, location, and usage patterns. Most homes will need 2–7 high-efficiency panels, along with optional battery storage for optimal performance.

Switching to solar is a smart investment, not just for your wallet, but for the environment too. And with energy prices continuing to rise, there’s never been a better time to explore solar.

Ready to start your journey? Use Eco Answers’ free quote comparison tool to find the best solar panel deals tailored to your home and hot tub needs.