If you’re considering installing a solar PV system in Northern Ireland, you may be wondering whether adding a battery storage system is worth it. Batteries allow you to store excess solar energy generated during the day for use later on, meaning you’re using more of your solar and buying less from the grid. But are they the right choice for your home? We’ll have a look at the benefits batteries offer, and some things to consider when making this decision.
How Do Solar Batteries Work?
A battery storage system works by storing extra electricity generated by your solar panels that your house doesn’t need. Instead of exporting this energy back to the grid, the battery saves it for later use—such as in the evening time when your panels are no longer producing electricity. This is an especially useful option for those homes where no-one is in for most of the day – whether you’re at work, school or just out and about. Batteries then allow these homes to still use the electricity that their solar panels have produced. Most batteries available today are lithium-ion and typically come in 5kW increments, allowing you to choose a size that suits your household’s energy needs.
Advantages of Adding a Battery
1. More Control Over Your Power
A battery allows you to use more of the electricity your solar panels generate instead of relying on the grid. This means you are less affected by changes in electricity prices, as you use a higher proportion of self-generated electricity from your solar panels.
2. Lower Electricity Bills
By using stored solar power instead of drawing from the grid, you can decrease your reliance on the more expensive daytime electricity rates. Over time, this can lead to significant savings.
3. Winter Benefits: Charging with Economy 7 or Day-Night Tariffs
During the darker winter months – or even those grey, rainy summer days when solar generation takes a hit—batteries can still help reduce your electricity costs. In Northern Ireland, many homes have access to Economy 7 or Day-Night tariffs, which offer cheaper electricity rates at night. By charging your battery overnight using these lower rates, you can wake up in the morning with a full battery and use that stored energy throughout the day, minimising your reliance on peak-rate electricity.
Things to Consider Before Getting a Battery
Upfront Cost
Battery storage adds to the overall cost of your solar PV system. However, the long-term savings on energy bills can help offset this investment. First Class Solar provides a comprehensive PV report following a survey, where your return-on-investment can be calculated and compared for a solar PV system with, or without a battery, giving you the information to make an informed decision.
System Size
Choosing the right battery size is crucial. Too small, and it won’t store enough energy; too large, and you may not use its full capacity efficiently – meaning you could be paying for storage you don’t actually need. The First Class Solar team will guide you through your options, considering not just your overall electricity usage but also your lifestyle—whether you’re home during the day, anticipating changes in household energy needs (such as family members moving in or out), and other key factors. Our goal is to help you find the perfect balance between cost-effectiveness and energy efficiency.
Lifespan & Warranty
Most lithium-ion batteries last 10-15 years, with cycle lengths of between 6,000-10,000 depending on brand. First Class Solar only installs batteries with minimum 10-year warranties to ensure peace of mind and long-term reliability.
Charging Strategy
If you plan to use Economy 7 or Day-Night tariffs, you need a system that can schedule charging at the cheapest times – your inverter WiFi monitoring app usually allows you to do this with ease, something that the First Class Solar technical team members will show you during your post-installation visit.
Do Solar Batteries Work During Power Cuts?
Most standard solar batteries do not function during power cuts. This built-in safety feature prevents electricity from being fed back into the grid, protecting utility workers from potential life-threatening electric hazards. However, if backup power is a priority for you, the premium SigEnergy Gateway system—approved in Northern Ireland and installed by First Class Solar—could be the option for you. This system requires specific installation conditions, such as being placed directly next to your NIE meter, and can only be offered after a thorough site survey by our technicians to ensure feasibility. Installation is more complex and may take longer, which can increase the overall cost.
Do Solar Batteries Work in the Cold?
Yes, solar batteries are tested to work in colder temperatures as can be seen in their “operating temperature” on each product datasheet – for example, the Duracell Energy Dura5 battery operates between -10°C~+55°C. However, the battery efficiency can be affected. Lithium-ion batteries, which are commonly used for solar storage, may experience reduced charging and discharging efficiency in extremely low temperatures. Most modern batteries have built-in temperature management systems to help regulate their performance. If you live in an area prone to very cold weather, our team may advise for your batteries to go in an attached garage or to have an insulated cover fitted if installed outside, to help maintain optimal battery function.
How do I get on the Economy 7/Day-Night Rate?
Switching to an Economy 7 or Day-Night tariff in Northern Ireland requires contacting your electricity supplier to request the change. These tariffs provide cheaper electricity rates during off-peak hours (typically overnight – see the Power NI site for example, making them ideal for homes with battery storage systems. Your supplier may need to install a special meter if you do not already have one. Before making the switch, it’s important to review your energy consumption patterns to ensure that the tariff will actually save you money. Our team can offer guidance on whether an Economy 7/Day-Night tariff is the right fit for your solar and battery setup.
“The landscape of solar batteries has changed drastically over the last 18 months. There has been rapid technical progress made by the old faithful, like Growatt and Dyness, as well as a large rise in new, strong competitors such as SigEnergy. With pricing of your standard 5kW battery coming down by more than 50%, storing your own power is as economically beneficial as it’s ever been” – Peter McCarty, Managing Director
So, Is a Solar Battery Right for You?
If you’re looking to maximise your solar investment, drop those electric bills, and gain energy independence, adding a battery is a smart move. It is especially beneficial if you are out of the house for most of the day and can’t make much use of your generated solar, or if you’re on the Economy 7 or Day-Night tariff, as you can charge the battery overnight when electricity is cheapest and use it throughout the day. At First Class Solar, we can help you choose the right battery storage solution for your home. Get in touch today to find out how you can benefit from adding a battery to your solar PV system!
