Experts in
Solar Batteries
The vast majority of First Class Solar customers are choosing to go with batteries to complement their solar PV system.
How do solar batteries work?
Batteries are used in conjunction with your solar panels and inverter to store excess electricity that’s produced by your system. As a simplified example, if your panels are producing 4kW of electricity over the course of 1 hour, but the house is only going to use 3kWh, the remaining 1kWh of power goes into your battery, rather than being sold back to the grid. This means that you’re able to store the electricity you produce during the day time, to use at night time when you get home from work.
This is what makes batteries very important for people who have solar, and either work full time out of home, or are just not usually home in the daytime. These people will need to come home, make dinner, do the washing, put the dishwasher on etc, and will want to use the electricity from the system that was produced during the daytime when they weren’t home – the battery is the key tool that allows this to happen.
What are the batteries made from?
First Class Solar only install lithium-ion batteries for several reasons – they tend to have a longer lifespan, higher efficiency and far fewer maintenance needs compared to the more traditional lead-acid batteries.
What size batteries should I get?
There are many different sizes available, but First Class Solar commonly installs 5kWh and 10kWh options. These can be added onto (linked together), provided that the batteries are the same size ie. if you wanted to add an additional 10kWh battery to your existing 5kWh, you would need to add two of the 5kWh’s.
There is no ‘one size fits all’ in this category as such, but we have asked our director Peter what his opinion is on battery sizing:
“This can vary massively from house to house, mainly depending on the yearly kilowatt usage of the house, the amount of PV the customer would like to install, and whether they have an electric car or not. If the customer has very high usage, for example, and will have very little left over to store in their battery, then the battery may look like a waste of time. The flip side of this is that if they are using an electric car and are set up on the cheap overnight EV electricity tariff, then a battery might be a great idea as they’ll be able to charge the battery overnight in the winter months, directly from the grid, meaning they wake up each day with full batteries of roughly half price electricity. This will allow them to save year round! So yes, it varies house to house, and your solar professional will be able to discuss the best options for your situation.”
Where in my home do the batteries go?
This is one of the main questions customers ask when considering getting—or adding—a battery to their solar system. Below are the various options, all of which can be discussed during a site survey:
This can be a good location if you have nowhere else to put the batteries. The batteries are very heavy and can be difficult to get into a roof space, but it is possible. Once installed, they’ll be out of the way. Modern batteries include in-built fire suppressants for peace of mind, and the system will be connected to your phone, so you’d very rarely need to climb into the roof space to check on it.
Many solar inverters and batteries are now fully water- and weather-proof, making outdoor installations increasingly popular. The latest 10kWh PowerBox G2 Dyness battery, for example, includes in-built heating for the winter months, so even during the cold spells we experience in Northern Ireland, your battery system will continue to operate effectively.
This is often an ideal location if space allows. An attached garage provides easy access to both the solar cables from the roof and the NIE meter on the house. If the garage is detached and the meter is on the house, a CAT5/CAT6 cable would need to be run between the garage and the meter for the battery to function correctly. If a duct already exists between the buildings, this is straightforward. If not, most quality solar companies can organise the installation of a duct, whether by cutting a trench or moling underground and bringing the duct up at either end.
This is less common, as most homeowners don’t want to sacrifice indoor space for the equipment. However, it is certainly possible, as long as the chosen room isn’t a bedroom and ventilation is adequate.
Do the solar batteries work in a power-cut?
Typically, no. As your solar PV system is grid-tied (meaning it is still connected to the main electricity grid), having the batteries work during a power-cut is a safety issue. There are some workarounds for this if this is a really important feature for you – in some homes, we can install a double off-grid socket, depending on the Northern Ireland Electricity (NIE) metering and earthing arrangement at your home.
Or, you could choose to go for a premium SigEnergy option where a Gateway is installed alongside your inverter and batteries, which allows for a seamless switchover to the batteries in the event of a power outage (https://www.sigenergy.com/en/products/gateway).
Some homes may not be suitable for this option, depending on the location of their meter and other factors – our skilled team will be able to talk through whether this is a workable option for you.
In Summary
A skilled and qualified team can install your battery and inverter almost anywhere in your home, as long as cable runs to your meter and switchboard are achievable. We always recommend discussing location options with your solar professional before signing a contract, to avoid any hiccups on installation day.
