While lithium-ion batteries are proliferating, the power grid must function reliably for days at a time, not just for a few hours buoyed by batteries. This is a challenge, especially during extreme weather. There are often energy-constrained times in peak summer or winter seasons, plus lulls in renewable energy generation. Though peaker plants have traditionally filled this need, they aren’t always clean energy.
With this in mind, let’s dive into new long-duration battery storage technologies and how they can impact the grid. Then explore how you can find places on the grid that are ideal for siting batteries for reliability and profitability.
Form Energy has a new system for clean, long-duration energy storage. This system delivers without the typical risks lithium-ion batteries face such as overheating and fire. This is because the cells are composed of porous, metallic-iron anodes submerged in a water-based electrolyte.
The iron-air technology works because the battery breathes in pumped oxygen, which reacts with the iron, and then rust forms on the iron, releasing energy. You can reverse this process when the battery charges.
A key to this technology working is balancing costs with efficiency. While iron is a very low-cost material, these batteries are about 40% efficient (compared to about 80% for lithium-ion batteries).
The footprint is similar to utility-scale, lithium-ion batteries.
All types and lengths of batteries serve a specific function in grid reliability. Utility resource planning is a key part of the energy transition. These types of technologies can fit into a least-cost portfolio and improve reliability at a lower cost to ratepayers.
Yes Energy’s solution, EnCompass, is designed to help market participants tackle the changing power grid. It can help with identifying locations on the grid where short-term and long-term batteries can arbitrage.
Source: Yes Energy. This shows an annual state of charge on a long-duration energy storage resource from an EnCompass optimization and demonstrates the hourly level of storage on the long-duration energy storage asset.
The above chart clearly shows the seasonality of how a long-duration energy storage asset ramps up on storage in certain months to apply that as generation in other months. This is key to a successful long-duration energy storage.
This sets long-duration energy storage apart from a regular battery, which can’t arbitrage monthly – most regular utility industry batteries only have two or four hours of storage, so they arbitrage over a day.
Looking up to 30 years in the future, EnCompass allows you to create multiple scenarios using shared datasets with scenarios grouped into structured folders that make it easy to set capital projects, outage dates, and initial conditions based on prior simulations. It helps you produce market price forecasts, analyze generation and transmission development, and make informed decisions in the transitioning power grid.
In addition, the National Database (input data to EnCompass) offers a readily available long-duration battery scenario for comparing the various types of technologies.
Last year, Great River Energy broke ground on a long-duration battery storage project, the culmination of analysis using EnCompass and other tools. In addition, EnCompass has been used in more than 30 IRP/regulatory filings and is used for PPA analysis, in support of financing, and other investment decisions.
While long-duration energy storage is an emerging technology, it offers promise. If you want to see how it could impact the grid or where to site an asset confidently, request a demo from our team.
About the author: Kailash Raman leads Form Energy's market development in the Western US, evaluating commercial opportunities across the region and engaging with utility, regulatory, and policy stakeholders to accelerate the deployment of multi-day storage. As a subject matter expert in energy systems modeling, he also works closely with electricity resource planners to identify the role that multi-day storage can play in addressing acute challenges on the grid. Kailash holds a Bachelor of Science in chemical engineering and a Master of Science in management science and engineering from Stanford University.
About the author: Norm Richardson built the EnCompass model, offered by Yes Energy. His past software and data experience includes leading a group of product managers and consultants at ABB (Ventyx and NewEnergy Associates, now Hitachi Energy) focused on power modeling software and databases, price forecasting, integrated resource planning, and economic transmission analysis.