In essence - battery energy storage systems are considerably more advanced than the batteries you keep in your kitchen drawer or insert in your children’s toys. A battery storage system can be charged by electricity generated from renewable energy, like wind and solar power.

Solar energy systems that can store their own electricity have three main components:

• Solar panels that absorb and convert the sun’s energy to DC electricity.
• A battery (or batteries) to store the electricity that is not used for when the solar panels aren't generating electricity.
• An inverter that converts DC electricity to AC ready for use in your lights, appliances etc.

Solar batteries typically last for 15 years and come with a 10-year warranty – though their capacity might decline in their later years. They have to perform repetitive, daily charging and draining cycles, and just like your phone’s battery, this eventually wears them out. Intelligent battery software uses algorithms to coordinate energy production and computerised control systems are used to decide when to store energy or to release it to the grid. Energy is released from the battery storage system during times of peak demand, keeping costs down and electricity flowing.

The battery size and its cost will depend on your current energy use and the size of any generation technologies you have installed. You may
also want to plan around future electricity use if you are intending to purchase an electric vehicle (EV) or heat your home with an air source heat pump.

As well as storing the electricity generated by your solar PV panels, a battery can also be used to store electricity bought from the grid at cheaper times of the day, with new smart dynamic tariffs that vary in price throughout the day. This can reduce your reliance on more expensive electricity during peak periods, with some tariffs even allowing you to ‘sell back’ during those periods. Most electricity storage systems also feature smart management capabilities, which allow you to track energy usage online or via an app on your smartphone.

If you already own solar panels at home, that’s not a problem; we can easily retrofit a solar battery to an existing solar PV system.

When the solar battery is installed, it must be either AC-coupled or DC-coupled, and this depends on the type of inverter that your solar panels are using. If your PV system has a microinverter, then the solar battery will have to be AC-coupled. This is the cheaper of the two options (as you won’t need to replace the inverter), and the installation process is fairly quick. However, this solution does lead to additional energy loss over time, because it involves converting the solar-generated electricity twice. On the other hand, if you don’t have a microinverter, then you’ll need to replace your existing inverter with one that can work with your solar battery. This is more expensive up front (your whole system will need to be rewired), but it only involves converting the solar-generated electricity once, so there is less energy loss in the long term. We can help you work out exactly what size battery you need and whether it needs to be AC-coupled or DC-coupled.