The UK may not be famous for endless sunshine, but when summer rolls around, homes with solar panels often find themselves generating more electricity than they need. If your system produces excess energy during bright days, you’re in a great position to save money — and even earn a bit. But are you really making the most of it? Make the Most of Excess Solar
In this guide, we’ll show you how to make the most of excess solar during sunny summer days, reduce your energy bills, and support a more sustainable lifestyle.
Why You’re Generating More Than You Use
Solar photovoltaic (PV) systems in the UK are typically designed to meet average daily needs. But in summer, when the sun rises early and sets late, your system can easily produce more electricity than your home can use — particularly if you’re out at work during the day and demand is low.
Think about it. On a hot sunny Tuesday lunchtime while your at work your panels could be producing between 3-10kW at any given time. At the same time the base load of a typical home is well under 1kW. This “excess” energy is typically exported back to the grid unless you have systems in place to store or divert it.
The good news? You can take control of that surplus and make it work harder for you.
1. Use Energy-Hungry Appliances During the Day
The simplest way to make use of your excess solar power is to shift your energy use to when the sun is shining where possible.
➤ Time Your Appliances
- Washing machine, tumble dryer, dishwasher: Run these between 10am and 3pm when solar output is usually highest.
- Slow cookers or air fryers: Prepare meals during peak solar hours where possible.
- Electric showers or immersion heaters: If you use these, try to time showers to late morning or early afternoon and/or set your hot water cylinder to heat up during peak solar hours.
➤ Use Smart Plugs
If you have appliances that do not have in built timers, smart plugs allow you to automate and stagger energy usage, ensuring you don’t overload your solar capacity but still make use of it efficiently.
2. Install a Solar/Home Battery
If you’re often out during peak generation hours, a solar battery is one of the best ways to capture that excess power for later use.
Benefits:
- Store electricity for evening and nighttime use when electricity is usually most expensive.
- Reduce grid dependence further.
- Boost your return on investment from your solar system.
What to Know:
- A 4–10 kWh battery is typically suitable for most UK households.
- Prices start around £3,000–£6,000.
- You can benefit from time-of-use tariffs like Octopus Agile/Go to store cheap grid electricity overnight as well.
3. Heat Water with an Immersion Diverter
A more affordable alternative to batteries is to divert excess solar energy to heat water using your immersion heater. This only works in homes with a hot water tank. Effectively the hot water tank acts like a big battery and reduces the need to use Gas or Oil to heat your water water throughout the day.
Devices like:
- MyEnergi Eddi
- Solic 200
- Solar iBoost+
These clever systems detect when your solar output exceeds your household demand and automatically redirects that surplus into your hot water tank, effectively giving you free hot water on sunny days.
Benefits:
- Cut gas, oil or paid electricity used for water heating.
- Simple, low-maintenance system.
- Can pay for itself in a few years.
4. Charge an Electric Vehicle (EV)
If you own an EV or plan to get one, summer solar is your best friend.
With a smart charger, like the myEnergi Zappi, you can ensure your EV is charged only using excess solar energy, avoiding costly grid electricity.
Top Tip:
- Schedule charging during mid-day when generation is highest.
- Combine with a solar battery for overnight range boosts.
It is worth noting that EV batteries are large (often up to nearly 100kWh) and will take a long time to charge fully on a domestic solar install. An average system may typically add 20-25% charge to your car on a nice sunny day.
5. Export and Earn with the Smart Export Guarantee (SEG)
If you have a smart meter and haven’t yet signed up, make sure you’re taking advantage of the Smart Export Guarantee (SEG) scheme, which replaced the Feed-in Tariff (FiT). At the time of writing you may be paid around £0.15p/kWh when you export excess solar back to the grid.
How it works:
- You get paid for every unit of electricity exported to the grid.
- Rates vary by supplier – from 1p to 15p per kWh.
Compare SEG tariffs and choose a supplier with the highest export rate. Octopus, E.ON Next, and ScottishPower are among the leading providers.
Even if you’re using other strategies to reduce exports, it’s still good to earn something back for what you don’t use.
6. Run a Dehumidifier or Air Purifier
On hot summer days, solar can power other useful devices:
- Dehumidifiers help keep homes dry and mould-free, especially in older UK properties.
- Air purifiers improve indoor air quality — particularly helpful during hayfever season.
Running them during peak generation hours ensures zero cost operation.
7. Power a Home Office or Garden Building
With hybrid working now the norm for many, powering your home office, studio, or garden room with solar during the day can lead to big savings.
Install a small secondary consumer unit or use battery-backed circuits to prioritise solar energy use in specific parts of your property.
8. Monitor, Adjust & Optimise
If you’re not measuring it, you’re not managing it.
Use energy monitoring tools like:
- SolarEdge, MyEnergi, or Sense apps
- Smart meters with real-time usage
- Home Assistant (for tech-savvy users)
By tracking your solar generation and usage patterns, you can spot trends, identify waste, and adjust your daily habits.
What About Overproduction?
On very sunny days, especially in low-demand homes, it’s possible to fully charge your battery, heat your water, and still have excess.
That’s OK — exporting the rest to the grid under SEG is still beneficial. But to go further, consider:
- Sharing power via community energy schemes (in development in some UK areas)
- Using peer-to-peer export platforms (coming soon to some suppliers)
- Investing in a larger battery if summer surplus is often wasted
Final Thoughts
In the UK, the number of homes installing solar PV continues to rise, and summer presents a golden opportunity to maximise returns. Whether it’s charging your EV, heating water, or simply shifting your energy use to the middle of the day, the key is to use what you generate as wisely as possible.
Taking control of your energy usage doesn’t just reduce bills — it also contributes to a lower-carbon, more resilient UK energy system. And that’s something worth celebrating, sunny or not.
