Is solar battery storage suitable? Battery storage installation systems There are two types of battery installation: DC and AC systems. DC battery systems A DC system is connected directly to the generation source (eg solar panels), before the electricity generation meter. You won’t need another inverter, which is more efficient, but charging and discharging is less efficient, so could affect your FIT (this isn’t usually recommended if you’re retrofitting a battery to an existing PV system). DC systems can’t be charged from the grid, according to the Energy Saving Trust. AC battery systems These are connected after the electricity generation meter. So you’ll need an AC-to-DC power unit to convert the electricity you generate into AC you can use in your home (and then back again to store it in your battery). AC systems are more expensive than DC systems, according to the Energy Saving Trust. But an AC system won’t affect your FITs payments, as the generation meter can register the total system output. If you have solar PV panels, or are planning to install them, then using battery storage to store electricity you’ve generated will help you to maximise the amount of renewable energy you use. This provides the building with added Energy Security Energy storage will reduce the electricity you use from the grid, and cut your bill. If your building is off-grid, it can help to reduce your use of fossil fuel back-up generators. Installing energy storage system is a long-term investment to help cut your energy bills, although this may not be your motivation. Whether a battery will save you money will depend on: the cost of installation the type of system installed (DC or AC, chemistry of the battery, connections) how it’s used (including the effectiveness of the control algorithm) the price of electricity (and how it changes during the lifetime of your system) the battery’s lifetime. Several systems come with a 10-year warranty. They require little maintenance, so the main cost is the initial installation. If you install it with solar PV (which can last 25 years or more), you should factor in the cost of replacing the battery.