Energy storage uncouples electricity production from consumption, improving grid stability and helping to lower power prices while decreasing greenhouse gas emissions and opening new opportunities for renewable energy deployment.
Energy storage comes in various forms. Pumped hydro storage (lifting water), batteries (chemical reactions), thermal (heat storage) and flywheel mass storage (spinning a wheel) are the four most prevalent options, each offering unique duration and efficiency benefits.
1. Flexibility
Energy storage devices can help to restore equilibrium to the electric power grid and ensure smooth operations.
Energy can be stored chemically (such as rechargeable batteries and hydroelectric dams), gravitationally potential (such as hydroelectric dams) or electrically (capacitors and superconducting systems). Thermal energy storage options also exist such as chilled water or ice, used to cool peak electricity consumption times; latent heat storage materials encapsulated walls or ceilings also serve to store latent heat energy.
Lithium-ion battery technology for grid-connected applications remains the dominant means of energy storage today, while redox flow batteries and supercapacitors have recently emerged as alternatives. Many of these technologies require large quantities of expensive rare earth metals which must be mined, necessitating skilled engineers who advocate for responsible sourcing of raw materials to develop them effectively.
2. Reliability
An effective energy system requires striking an ideal balance between supply and demand for electricity, and energy storage technologies like pumping or megawatt-scale technologies or behind the meter battery technologies can play an integral role in maintaining that equilibrium.
Storage systems offer redundancy, grid stability and other essential capabilities essential to maintaining energy balances, making them an integral component of renewable energy integration, particularly intermittent generation.
Energy storage needs have grown increasingly pressing due to decreased reliance on fossil fuel baseload power, increased intermittent renewable investments and the burgeoning adoption of distributed energy resources. Unfortunately, methods and models for valuing storage use cases remain evolving.
Nantucket Island study results revealed that cost-benefit analyses used to calculate performance payments to customer-sited batteries significantly underestimate the value of winter peaking capacity services from customer-sited batteries, according to SEIA’s statement. SEIA believes this must be addressed and level the playing field for new storage development across the nation.
3. Economical
Storage technology enables consumers and businesses to save on electricity costs by shifting consumption away from peak load periods, while simultaneously creating high quality jobs across America and supporting manufacturing revival efforts.
Economic considerations when choosing electricity storage options vary significantly based on required storage duration, efficiency and scalability. Pumped hydro storage, hydrogen market-based systems and batteries for personal use are examples of currently available technologies.
As part of expanding electricity production from variable renewables, discussions about additional capacities of energy storage are underway. According to previous analyses conducted by Zerrahn and Schill, even an increase of up to 80% in VARET share requires only moderate additional storage capacities if its peaks can be effectively shed from the grid. It should be noted, however, that storage requirements could increase further without alternative flexibility measures like household prosumage, demand-side management by households or sector coupling.
4. Environmentally friendly
Energy storage allows us to integrate more solar, wind and distributed generation resources into the electric grid by decoupling supply and demand. Renewables can shift gears more freely; and overall it makes the grid operate more efficiently and reliably while decreasing GHG emissions.
Battery energy storage systems use electricity to alter chemical bonds in their materials and generate power when needed later on. Lithium-ion batteries are currently the most prevalent option; however other technologies like thermal ice-storage technology offer benefits by lowering peak electricity rates for businesses and residents, using non-toxic components like water as opposed to toxic elements like lithium.
While all energy storage technologies pose some chemistry-specific hazards under fault conditions, their risks tend to be contained to their physical boundaries and any fires which do erupt are usually managed without endangering wider communities; battery manufacturers advise allowing fires to burn themselves out to lower risk of spills and spread of toxic fumes.