“Energy storage” encompasses a wide array of technologies, applications, and public policy inducementsFor policy analysis, the user is able to sort and filter according to the following criteria:
- policy source (state or U.S. federal)
- grid interconnection, including secondary distribution
- ownership model (customer-, utility-, or third-party-owned)
- utility type (cooperative, investor-owned, or public)
- service/use case (e.g., electric bill management, supply reserve capacity, frequency regulation, etc.).
Four major energy storage technology families can be distinguished, including:
- electro-chemical – including electro-chemical capacitors as well as all types of batteries (flow, lead acid, lithium ion, metal air, sodium-based, and zinc air)
- electro-mechanical – comprised of compressed air storage, flywheels, and gravitational systems
- pumped hydro – both open and closed loop
- thermal storage – ice, and molten salt
The U.S. energy storage pipeline: Pumped hydro still dominates, but its position is weakening
The total rated power capacity of currently operating U.S. energy storage comes to 21,484 MW. (Over the years, 15,584 MW has been decommissioned, and 7,684 MW is currently offline or under repair). This U.S. capacity will grow by 5,760 MW in additional energy storage capacity, going by those projects that have been announced, are contracted, or are under construction.
We see that pumped hydropower storage remains the giant in the field, with a pipeline of 4,150 MW of rated power to add to existing operations of 20,356 MW. However, among the technologies, it is growing the slowest, adding only 20% of capacity. Thermal storage is expected to add 302 MW of rated power to the existing 553 MW (an increase of 54%). Electro-chemical approaches will add 602 MW, a rise of 148% over the existing 405 MW of rated power capacity. The most dramatic pipeline growth, relative to existing capacity, is with the electro-mechanical technologies such as compressed air storage and flywheels, a finding that runs counter to prevailing assumptions in the market. An additional 706 MW of power capacity is expected to come on line in this area, an increase of 418% over the present capacity of 169 MW.
At the top of this chart we see the thermal projects that have been announced, contracted or are under construction. Next are the clusters for electro-mechanical and battery technologies. No projects are listed for sodium-based or zinc manganese dioxide batteries, or for electric capacitors. What is the takeaway message for investors? Future tendencies may not all be about batteries, and one would be wise to consider all available energy storage applications, depending on the project needs.
Finally, where in the United States are most of these projects headed? According to research by CleanTechnica, California is leading the way, likely due to the recent state-level energy storage mandate.
- “The DOE Global Energy Storage Database provides free, up-to-date information on grid-connected energy storage projects and relevant state and federal policies. All information is vetted through a third-party verification process. All data can be exported to Excel or PDF. Our hope is that this site will contribute to the rapid development and deployment of energy storage technologies.” U.S. Department of Energy, 3/16
- “Global Energy Storage Pipeline Increases 45% In Q4’15: IHS – According to analytics company IHS, battery cost reductions, government funding programs, and utility tenders all contributed to a 45% increase in the global energy storage pipeline in Q4’15, with the pipeline of planned battery projects and flywheel projects reaching 1.6 GW..” CleanTechnica.com, 1/16
- “Global Energy Storage Pipeline Increases 45% In Q4’15: IHS – According to analytics company IHS, battery cost reductions, government funding programs, and utility tenders all contributed to a 45% increase in the global energy storage pipeline in Q4’15, with the pipeline of planned battery projects and flywheel projects reaching 1.6 GW..” CleanTechnica.com, 11/25/15
- “The energy storage market is maturing, and there's now less focus on physics and more emphasis on projects, system intelligence and grid integration. It’s when project development and execution become quotidian and efficient that energy markets really take off.” GTM2, 12/15
- “Globally, the total installed capacity of electric energy storage is over 141 GW -- but 99% of that is in the form of pumped storage hydropower systems.”