Energy storage can help meet demand-supply imbalances while simultaneously supporting renewable wind and solar technologies into systems previously dependent on fossil fuels.
Batteries are one of the most scalable energy storage technologies. Just like those found in cell phones, utility-scale battery energy storage systems are capable of storing electricity until necessary, then discharging it when required.
Battery Storage
Energy storage is an indispensable component of renewable-energy production, allowing alternative energies such as wind and solar to make a sustained contribution despite their inherently intermittent nature. Furthermore, storage devices serve to lower electricity prices during peak demand periods on hot summer days when air conditioners run more often and households consume more electricity.
ESS systems may be found anywhere from within an electric grid transmission network and distribution network to customer sites or co-located with renewable-energy sources. In the US alone, there is currently over 708MW of large battery energy storage systems operating that are managed by organizations charged with maintaining grid stability (ISOs and RTOs).
ESS technology can be utilized to reduce customer-owned demand charges during electricity peak pricing periods or participate in utility demand-side management programs. Furthermore, these systems may also be integrated into microgrids that serve specific geographic regions or communities.
Hydrogen Storage
Hydrogen storage offers more versatile seasonal energy storage than batteries, typically lasting from minutes to several days or weeks at most. Hydrogen gas can be compressed underground for storage while liquid forms absorb it directly and store it. Once it has been recharged it can be used in fuel cells to produce electricity.
This technology makes possible the replacement of fossil-fuel peaker plants – typically located in areas with high electricity demand and often contributing to air pollution – with greener alternatives such as pumped hydro and CAES systems, where energy can be stored locally but also transported long distances via dedicated pipelines. However, overall energy chain efficiency of hydrogen production, storage, refueling is lower – it only exceeds 25% [68].
Wind Storage
Energy storage is vital to the success of renewables in modern power systems, acting as an intermediary between intermittent wind power production and its constant demand from production equipment.
Energy storage also helps us avoid cost spikes on our electric bills. Energy storage devices can reduce demand during peak times – like hot summer days when everyone turns their air conditioning up full blast!
Grid-scale energy storage technologies (such as batteries) can play an instrumental role in stabilizing the grid, acting as an invaluable buffer when wind power output exceeds what the grid needs or can accommodate. Any excess electricity is then stored for later withdrawal – smoothing out its peak-and-valley patterns while increasing stability, quality power output and suppressing low frequency oscillations of the grid while simultaneously saving on transmission costs by eliminating upgrades of poles, wires and substations making up this vital infrastructure.
Solar Storage
Energy storage systems can make solar energy systems smarter and cleaner by acting as backup power sources that safeguard against power outages while taking advantage of time-of-use pricing systems offered by utilities. Energy storage also protects homeowners against power outages while giving them more opportunities to take advantage of time-of-use pricing systems offered by their utility provider.
Storage can also help balance the electric load. Without storage, electricity must be produced as it’s needed – meaning more expensive rates during peak demand times – like on hot summer afternoons when air conditioners are running and electronics are being used widely. Storage helps manage price spikes and makes switching renewable electricity sources simpler for consumers.
NREL researchers are exploring the unique economic and grid benefits of solar-plus-storage systems, which combine photovoltaic (PV) systems with batteries for energy storage. Battery technology such as lithium-ion plays an increasingly prominent role as its costs continue to fall, providing economic and grid benefits of this hybrid approach to renewables.