Batteries allow the user to capture electricity from a renewable system and help to eliminate the intermittency problems associated with solar and wind generation in particular. A variety of different battery technologies are available including relatively heavy, traditional lead acid batteries with low energy densities to much lighter but more expensive lithium ion batteries with higher energy densities. Lithium ion battery costs have tumbled in recent years and in 2021 were 89% cheaper in real terms than in 2010.

One of the main financial benefits from deploying a battery is from load shifting. This is where excess electricity produced from, for example, roof mounted solar can be used to charge a battery at zero marginal cost ready for discharge when grid supplied electricity is at its most expensive. The same principle works with a standalone battery which can also help shift demand for grid supplied electricity. With a time of use tariff like Economy 7, where night time electricity is less expensive than during the day, a battery can be used to discharge stored electricity when rates are more expensive. Batteries can also be utilised to generate additional revenue streams through the provision of ancillary services to National Grid. Such services can help National Grid maintain the frequency of the grid at 50hz and provide additional capacity when required.

The main physical constraints to battery deployment are space availability and suitability. Temperature and atmospheric conditions should also be considered as they will have an impact on the life span of the battery.