If you already have solar panels, or you are planning a new system, one question comes up time and time again. How do you make the most of the energy your panels generate?
For many Surrey homeowners, the choice comes down to battery storage or an immersion controller. Both are designed to reduce wasted solar energy and lower reliance on the grid, but they work in very different ways.
So which option actually saves more money, and which one is right for your home?
Solar panels often produce more electricity than a household needs at certain points in the day, especially around midday. Without a way to use or store that excess energy, it is exported back to the grid.
While solar export payments are available, they are usually far lower than the cost of buying electricity back later. That is why increasing solar self-consumption is key to maximising savings from your system.
This is where batteries and immersion controllers come in.
A solar battery stores excess electricity generated by your panels during the day so it can be used later. Instead of exporting unused energy, it is saved and released when your home needs it.
This is particularly useful in the evenings when solar production drops but household demand increases.
Battery storage can help:
For many households, a battery significantly increases how much of their own solar energy they use.
An immersion controller takes surplus solar electricity and diverts it to your immersion heater. Instead of exporting energy, it heats your water using solar power.
This means hot water produced by your panels rather than electricity or gas from the grid.
Immersion controllers are automatic and work quietly in the background, using only excess energy that would otherwise be lost.
They are especially effective in homes with:
The big question is which option saves more.
Battery storage typically offers higher overall savings because it can power a wide range of household appliances, not just hot water. By reducing evening grid use, batteries often cut electricity bills more significantly over time.
Immersion controllers tend to offer more targeted savings. They reduce the cost of heating water, which can still be a meaningful part of household energy use, particularly in homes with electric immersion heaters.
In simple terms:
Cost is a key factor for many Surrey homeowners.
Immersion controllers are generally much more affordable to install. They involve lower upfront costs and can start delivering savings quickly, making them an attractive option for households wanting a simple upgrade.
Battery systems require a larger initial investment. However, they also deliver broader benefits and higher long-term savings, especially as electricity prices rise.
The right choice often depends on budget, energy usage patterns, and long-term plans.
Homes that use most of their energy during the day, such as those with remote workers, often benefit greatly from immersion controllers. Solar surplus is common during working hours, making hot water an ideal place to use it.
Homes with higher evening and overnight energy use usually see better value from battery storage. This includes families, electric vehicle owners, or anyone who uses appliances after dark.
Yes, and in many cases this delivers the best results.
A battery can be prioritised to store energy first, with any remaining surplus then diverted to heat water via an immersion controller. This approach maximises self-consumption and reduces both electricity and water heating costs.
For some Surrey homes, combining both options creates a flexible, future-proof energy system.
Battery systems require space, usually indoors or in a garage. They also need careful system design to ensure compatibility with your inverter and existing setup.
Immersion controllers are smaller and simpler to install, but they rely on having a suitable hot water cylinder.
A professional assessment is essential to ensure whichever option you choose works safely and efficiently.
There is no single answer that fits every household.
Battery storage generally offers greater overall savings and energy independence, especially for homes with higher electricity use outside daylight hours.
Immersion controllers offer excellent value for money, lower upfront costs, and a simple way to reduce wasted solar energy by heating water for free.
The best solution depends on how your home uses energy, when you use it, and what you want to achieve long term.
At Sheerwater Solar, we look at the full picture. Your household habits, your existing system, your future plans, and your budget.
Whether that leads to a battery, an immersion controller, or a combination of both, the goal is always the same. To help you get more from your solar investment and reduce your reliance on the grid.
The smartest solar systems are not just about generating energy. They are about using it in the right way, at the right time.
If you’d like to speak to our experts, get in touch today, we’re always happy to help.
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Reaching out to Sheerwater Solar is straightforward and hassle-free. Whether you’re interested in solar panels for your home or business in Woking, we’re here to guide you every step of the way. You can contact us directly by calling 01932 627 555 or by sending an email to info@sheerwatersolar.co.uk.
Alternatively, fill in our online form for a swift response.
What happens next?
In most cases, we’ll need to conduct an on-site survey at your property to assess the feasibility and provide you with a tailored quote. This visit allows us to understand your specific needs and explore the potential for renewable energy solutions. Following the survey, we’ll discuss the best options for integrating solar energy into your property, including detailed costs and the installation process.
We’re excited to assist you on your journey to renewable energy and look forward to hearing from you.