Battery storage

• Solar self-consumption. Stores surplus generated in the day for use later, instead of exporting it at a much lower rate. Usually the strongest single reason to add one.
• Load shifting. Charges when power is cheaper and discharges when it is more expensive, which matters more as time-of-use pricing spreads.
• Peak demand management. Discharging across a demand peak can reduce the capacity a site needs to reserve, and capacity is charged every day.

A battery does not reduce the energy a site uses. Round-trip losses mean it uses slightly more. The value is entirely in when the energy is used and what that timing is worth.

Anyone presenting storage as an energy reduction is describing it wrongly.

The shape of your tariff, the shape of your load, whether you are also generating, and the installed cost. Change any one of those and the answer changes.

It is the technology where the commercial model matters most and where we most often advise against proceeding. We would rather tell you that than sell you a battery that never earns its cost.

If the objective is managing a demand peak, check the agreed capacity position first. Reducing capacity that is never used costs nothing and recurs annually. A battery bought to solve a capacity problem that a form would have solved is an expensive answer to a cheap question.