Home battery storage: how it works and whether it is worth it

A home battery charges up when electricity is cheap or free, and discharges when it would otherwise be expensive. There are two common ways to fill it: - From solar: surplus daytime generation that you are not using is stored instead of exported. - From the grid: on a time-of-use tariff, the battery charges during the cheap overnight window and powers your home through the expensive evening peak.

The battery sits alongside your existing electrics with its own inverter or a hybrid inverter, and management software decides when to charge and discharge.

No. A battery is most powerful paired with solar, but a standalone battery can still save money for households on a time-of-use electricity tariff by shifting usage from expensive peak hours to cheap off-peak hours.

That said, the strongest case is usually solar plus battery, because you are storing electricity you generated for free rather than buying it, even at a low rate.

A battery tends to be worth it when: - You have solar and currently export a lot of surplus you could be using yourself. - You are on, or can switch to, a tariff with a cheap off-peak rate. - Your evening electricity usage is high, when grid power is most expensive.

It is less compelling if your usage is very low, you have no solar, and you are on a flat tariff with no cheap window to exploit. We will model your specific case rather than assume.

Home batteries are rated for a large number of charge and discharge cycles and typically carry a warranty covering many years of daily use. Capacity gradually reduces over the battery's life rather than failing suddenly. We match battery capacity to your usage so it is neither undersized nor paying for storage you never use.

The Tesla Powerwall is one of the best-known home batteries, and we install it alongside other leading brands. The right battery for you depends on the capacity you need, whether you want whole-home backup during a power cut, and how it integrates with your solar and tariff. We recommend based on fit, not brand name.

Some batteries can provide backup power during an outage, but this is a specific capability that has to be designed in, not something every battery does by default. If keeping essential circuits running during a cut matters to you, tell us and we will specify a system that supports it.