Energy storage refers to any method that allows one to save energy for later use, from chemical energy stored during photosynthesis in plants to pumping water behind hydroelectric dams back behind to lithium-ion battery storage on an entire grid level.
ESS can assist in balancing electricity supply and demand on multiple timescales, including second-by-second basis, to help improve power quality by minimizing surges or sags in power quality.
Boosting the use of renewable energy
Energy storage is integral in making renewable energy more reliable and accessible, helping businesses stay operational during power outages while cutting their costs. Storing solar or wind energy reduces demand from older power plants while helping businesses maintain operations despite energy outages, helping keep costs under control and cutting electricity consumption altogether.
Energy storage also helps prevent renewable energy from going to waste when its output exceeds demand, and can store this surplus renewable power before returning it to the grid during high demand periods to help prevent price spikes for electricity customers.
Residential and commercial storage systems also play a vital role in helping lower electricity bills by charging at times of lower demand, then using stored energy during periods of higher peak usage at higher rates. This helps offset the need for pollution-emitting peak power plants that would increase greenhouse gas emissions; additionally energy storage reduces frequency regulation costs with its lower costs than competing technologies; battery energy storage offers this service at reduced prices than others technologies.
Boosting community resiliency
Energy storage is an integral component of power resiliency, helping prevent or minimize power outages during extreme heat or cold, natural disasters, or during other critical situations such as extreme temperatures. Outages cost Americans billions each year in lost productivity, food spoilage and property damage – not to mention possible health complications if critical services like hospitals are disrupted.
Energy storage devices can help meet peak power demand in densely populated urban areas, alleviating strain on the grid and helping prevent spikes in electricity prices. When combined with community solar, storage can even serve as localized backup power sources for homes and businesses alike.
Resiliency benefits of energy storage can be compounded for communities located away from the electrical grid, such as rural homes or islands, which may be more vulnerable to disruptions in power supplies. Energy storage provides back-up power as well as helping shift renewable generation toward when it is most needed, increasing reliability in such communities and helping ensure renewable power production at times when its needed most.
Increasing access to electricity for low-income communities
Energy storage provides low-income communities with greater access to renewables while simultaneously lowering energy costs by providing backup power and decreasing demand. It can even replace fossil fuel peaker plants which often operate nearby during periods of peak electricity demand – potentially contributing to air pollution and health impacts.
Policymakers who aim to maximize benefits for low-income communities when designing energy storage programs must take several factors into account when designing the programs. Policymakers should prioritize community engagement and capacity building activities that foster education about energy storage projects as well as hiring/entrepreneurship opportunities within solar+storage project structures.
Finally, they should utilize existing program resources to support energy storage projects in LMI communities, including utility procurement targets, finance programs, and energy efficiency programs. Techno-economic modeling may be employed to explore system design options which maximize benefits to LMI communities while simultaneously meeting financial feasibility requirements while aligning with community goals.
Increasing grid stability
Energy storage devices can improve grid stability by smoothing out the variable outputs of renewable energy sources such as solar or wind power, charging during periods of excess generation from these sources and discharging when peak demand hits, thus preventing electricity from either being cut off from the grid or going to waste.
ESSs provide additional ancillary services by quickly responding to electricity demand fluctuations on second-to-second timescales to maintain electric grid frequency characteristics and increase quality of power supply. Fast response (ramping) ESSs such as batteries and flywheels are particularly suited to this use while thermal energy storage systems such as molten salt storage can be employed in cogeneration plants or fuel cells that generate both electricity and heat simultaneously.
ESSs can be located across various segments of the electric grid, including transmission and distribution networks, power plants and residential and commercial building levels. As costs continue to decrease and new technologies emerge, their deployment will increase quickly allowing immense flexibility within the grid.