As battery storage costs continue to fall, more energy storage technologies emerge, and as world powers continue their transition to cleaner energy economies, energy storage will play an even bigger role.
One of the reasons for the accelerated deployment of energy storage is that it increases the flexibility of grid operations, provides multiple services, and can be used for different applications. Energy storage systems can also be located in multiple parts of the grid—transmission networks, distribution networks (where electricity is delivered to consumers), generators (for example, collocated with wind or solar), and some smaller-scale commercial buildings or residential.
Since some renewable energy technologies, such as wind and solar, have variable outputs, storage technologies have great potential for smoothing the supply of electricity from these sources and ensuring that generation supply matches demand. If charged during periods of excess renewable energy generation and discharged when demand increases, energy storage can help maximize the use of renewable energy and ensure less waste. Residential battery storage can help utilities balance power customer demand and power supply to better align the more variable wind and solar supply with power demand.
More broadly, storage can provide power in response to changes or dips in power, provide power frequency and voltage regulation, and delay or avoid costly investments in transmission and distribution to reduce congestion. Energy storage is also valued for its rapid response – battery storage can start discharging to the grid very quickly in fractions of a second, while traditional thermal power plants take hours to restart. This rapid response is important to ensure grid stability when demand unexpectedly increases.
The deployment of energy storage can bring benefits to communities historically overburdened by the effects of pollution and climate change.
A key advantage of energy storage is its ability to provide grid services currently provided by fossil fuel peakers (or "peakers"). Why is energy storage a problem? That's because these power plants only operate during times of extremely high demand for electricity, such as during high temperatures, for a limited time throughout the year. Most peaks are powered by natural gas (though some even use coal, oil and diesel fuel), which increases air pollution and exacerbates the already poor public health impact of these overburdened communities. Energy storage can replace existing polluting peak power plants and can eliminate the need to develop additional power plants in the future. Battery storage is already cheaper than the gas turbines that provide this service, which means that existing peakers will be replaced more quickly over the next few years.
By charging storage facilities with energy from renewable sources, we can reduce greenhouse gas emissions, reduce our reliance on dirty fossil fuel factories that cause pollution and negative health outcomes in communities, and even improve community resilience through solar-plus-storage systems ability.