Energy storage refers to any method of capturing and storing energy for later use, such as battery systems in electric vehicles and flywheels which store kinetic energy.
Utility-scale storage technologies such as pumped hydro provide vital services that balance electricity supply and demand on an hour-by-hour basis, while residential and commercial battery storage has seen exponential growth thanks to falling prices.
Resilience
Energy resilience should be an organizational priority given that power outages can last days and severely interrupt business operations. Furthermore, extreme weather events related to climate catastrophe are expected to become more severe over time, straining grid infrastructure more and leading to longer and more frequent outages.
Energy storage can help enhance energy resilience in various ways, from providing backup power for individuals and businesses during grid outages, to smoothing out high prices on electric bills by lowering peak demand charges. A household solar system equipped with a small battery provides an easy way to become more resilient while simultaneously cutting costs during times of high electricity demand.
Advanced energy resilience solutions use energy storage to form microgrids or resiliency hubs, often combined with solar or other forms of renewable energy sources like community solar. For instance, one marine corps air station developed one of the country’s most sophisticated solar-plus-storage microgrids to address their critical power resilience needs.
Flexibility
Energy storage provides an effective means to balance supply and demand in ways that improve both its economics and efficiency. Storing renewable energy during times of high production before releasing it back onto the grid during periods of peak demand helps prevent cost spikes as well as avoid expensive fossil fuel power plants during these crucial moments.
ESSs can also help commercial and industrial electricity demand charges by reducing consumption during utility peak demand periods. They can also be integrated with renewables to smooth their variable output by absorbing excess wind or solar generation and dispensing it during off-peak hours.
ESS technologies range from rechargeable batteries (such as those found in home EV chargers), hydroelectric dams that store water to be converted into electricity at night, and thermal storage systems like molten salts used for concentrating solar power production, to more sophisticated approaches including pumped storage hydroelectric dams, compressed air energy storage devices such as flywheels and superconducting magnetic coils for large-scale applications.
Cost
Energy storage solutions allow businesses and sectors to store energy from cheap sources when prices are low and use it when prices increase, helping reduce their energy bills, meet sustainability objectives and meet climate targets.
Electricity storage systems (ESSs) can store and deliver electricity over an extended time period – anything from seconds to hours – as well as providing services such as frequency response or reserve capacity to the grid. They may be located anywhere along its transmission or distribution networks, power plants or end-use facilities.
ESSs can play a vital role in transitioning to a low carbon economy by helping balance electricity supply and demand, improve power quality and integrate renewables into the grid. They offer large deployment potential at relatively low costs: for instance, IRENA estimates lithium battery costs for stationary applications could decline 50%-60% by 2030.
Climate Change
Energy storage can be an invaluable tool for integrating renewables and reducing greenhouse gas emissions, but its success depends on how it’s implemented – for instance, replacing natural gas plants with pumped hydro energy storage can cut carbon dioxide emissions by as much as 60%!
Longer duration energy storage provides other important benefits, including decreasing seasonality of electricity supply by running a pumped storage hydroelectric dam on an annual cycle instead of daily.
Thermal energy storage allows electricity to be saved over the summer for use during winter; for instance, the Solar Tres Power Tower in Spain and similar projects use special conduits to pump molten salt that heats up when required and converts it to electricity when required; these systems are known as long-duration energy storage; some studies optimize size and operation based on economic criteria.