Installing solar panels on your roof is a great way of generating your own clean, renewable energy. But given that this electricity can’t always be used immediately, is it possible to add batteries to your existing solar system to prevent it from being wasted?
In short, the answer is yes.
At Apex Doma, we’re here to explain how solar battery storage works, guide you on what to consider when adding batteries to an existing solar system, and outline the pros and cons of doing so.
What Is Solar Panel Battery Storage?
Solar panel battery storage (or solar batteries) allows you to store excess electricity generated by your solar panels for later use.
How Does Solar Battery Storage Work?
Solar panels generate the most electricity during the day, when energy consumption is often at its lowest.
Solar batteries store excess energy generated by solar panels for later use.
The process is fairly simple:
- Solar cells in the panel convert sunlight into direct current (DC) electricity.
- This DC flows into an inverter, which converts it to alternating current (AC) to power your home and any electrical devices.
- If your electricity usage is less than what is being produced, then the DC is taken from the solar panels and used to charge a battery.
- Should you need electricity at night or when the sun is not shining, you can use the energy stored in your solar battery.
Whilst any unused electricity can be sold back to the grid, you could benefit more by installing a solar battery to store this excess electricity and use it to power your home later on.
The best part is that this happens automatically. Using built-in algorithms, intelligent solar battery software can calculate when to use, store, or discharge excess energy back to the grid to achieve optimal cost savings.
Can I Add Batteries to My Solar System?
Yes, you can add batteries to your solar system.
At Apex Doma, we offer solar batteries as part of our solar panel installation packages, or we can help you install them yourself.
Our team of dedicated solar and battery storage experts is on hand should you need them to help install solar batteries, answer any questions, or offer guidance to help choose the power storage solution that’s right for you.
Adding Batteries to an Existing Solar System in the UK
Adding a battery to an existing solar system is always an option.
For more complex solar systems or when solar PV panels are already installed on a property, you’ll need a separate battery and PV inverters. Here, the solar battery is joined to the PV system on the AC side of the inverter (also known as AC-connected or AC-coupled batteries).
Different-sized batteries are available depending on the storage capacity you need and the specifications of your existing solar system. Retrofitting a solar battery may also involve adding a hybrid inverter or modifying your home circuit board or wiring.
All of this can be discussed during your free consultation to help you find a product that’s right for you and your home. Our team of battery storage experts have installed systems of all shapes and sizes, and we’ll find the best solution for your needs.
If your existing system benefits from the government’s Feed In Tariff (FIT) scheme, then you can continue to make use of this. Your FIT payment will remain the same as you’re paid for all the energy you generate.
To protect these profitable payments alongside battery storage, we’d recommend having an AC-coupled system. This involves leaving the existing system as it is and installing a second inverter to manage the charging and discharging of the battery. This allows maximum energy to pass through your FIT-registered meter, providing you with the highest possible financial return from the scheme.
For more information, read our guide on ‘Adding Battery Storage to Your Existing Solar Setup with a Feed-In Tariff (FIT)’
How Many Batteries Can I Add to My Solar System?
The number of batteries you can add to a solar system depends on:
- Your energy consumption
- The capacity of the existing solar PV panels and their level of output
- The specifications and compatibility of your inverter and charge controller.
- Any manufacturer guidelines that need to be adhered to
- Amount of physical space available and any safety concerns
While there is no universal limit on the number of batteries you can install, technical and practical limits may decide the final number. This is where a professional assessment from our team will help you choose the ideal number of batteries for your residential solar system.
For further details, check out our guide on the ‘top 5 things to consider before buying solar and battery storage’.
Pros and Cons of Solar Battery Storage
Pros
Solar battery storage stores the power generated by your solar panels for later use, reducing wastage. This reduces your reliance on the grid, leading to less imported electricity and lower energy bills.
According to the UK Government, families could save around £500 a year on their energy bills by installing rooftop solar panels.
Some intelligent systems automatically switch to battery power during peak billing hours, saving you even more money.
Solar battery storage also provides greater energy security as a backup power source during blackouts and extended outages. You can also use this surplus electricity to charge your electric vehicle, further reducing your running costs.
If you’re eligible for the Feed-In Tariff scheme or Smart Export Guarantee, any excess electricity produced by your solar panels will go to waste without battery storage, so it’s definitely something worth considering.
Cons
There are some considerations when retrofitting a battery to an existing solar system.
AC-coupled batteries are better suited than DC-coupled ones. DC-coupled systems are better for new installations and new-build properties that don’t have existing circuit boards, breakers, and wiring. AC-coupled solar batteries need a storage inverter, whereas DC-coupled systems require a solar inverter.
The project costs may increase if additional components are needed, but this will depend on the make, model, and complexity of your system.
Our team will guide you through these points during your consultation. We’ll find you the best solution for your home and help you maximise your return on investment.
For more information, check out our guide on ‘Are Solar Battery Storage Systems Worth It?’ and ‘AC vs. DC Coupled Batteries: Which Is Best for Your UK Home?’.
Why Choose Apex Doma When Adding Battery Storage to an Existing Solar System?
Here at Apex Doma, we’re dedicated to excellence. As an NICEIC Approved Contractor alongside our Which? Trusted Trader status and MCS & RECC registrations.
Our engineer-led approach means you won’t encounter salespeople along the journey; just a team of solar experts whose primary goal is to find a battery storage solution that works for you and your property.
A blend of solid infrastructure, slick processes, and professionalism empowers us to deliver an efficient, dependable, and cost-effective service for a range of solar projects, regardless of size or complexity.
Speak with one of our team members for a free, no-obligation quote to help find the solar battery storage that’s right for you.
Final Thoughts
Adding battery storage to an existing solar system is an excellent way to maximise your return on investment, save money on your energy bills, and decrease your reliance on the National Grid.
They also give you greater autonomy in your energy consumption, where this electricity comes from, and how you use it.
Retrofitting solar battery storage is now easier than ever before, with a greater range of solutions on the market to meet everyone’s energy needs.
Our team of experienced, dedicated, and reliable experts is here to discuss the options available to you and to offer our expertise in determining which battery would be best for your existing solar system.
Contact us to arrange a virtual quote, on-site survey, or to answer any queries you may have.
You can visit our Solar Advice Hub for the latest insights and research into solar energy in the UK, including further information on adding battery storage to an existing solar system.
FAQs About Adding Batteries to an Existing Solar System
A solar battery is a rechargeable energy storage system that stores excess electricity generated by solar PV panels during the day for use at other times when energy production is less efficient (such as at night, on cloudy or rainy days, or during power outages).
If you don’t have a battery fitted to your solar system, you won’t be able to store any of your solar energy, and you’ll have to use the generated power straight away or export it to the grid.
This’ll cost you a significant amount of money, as you’ll have no control over whether you use electricity from your provider during on-peak or off-peak hours.
Installing solar battery storage with your solar panels increases the clean energy you can use around the house to power your devices, especially during off-peak hours and when the sun is not shining. It’ll give you more independence from the grid, saving you money on your energy bills.
Yes, adding a battery to an existing solar system is almost always worth it.
It’ll allow you to maximise your return on investment, reduce your reliance on the grid, and give you more control over where your electricity comes from during peak billing hours. Over time, this will save you money and reduce your energy bills.
Solar battery storage also boosts your energy security by providing a renewable, clean source of electricity. It also reduces wastage by storing excess electricity for you to use whenever you need it.
Yes, you can use solar panels without a battery when it’s part of a grid-tier system. However, adding battery storage to an existing solar system is becoming increasingly common, as it stores electricity for use at night or when energy production is limited (such as on cloudier days or during a power cut).
