The “Top Ten Breakthrough Technologies in the World” selected every year have strong technological “source” attributes. In long-term grid energy storage batteries, cheap and durable iron-based batteries can help distribute the supply pressure of renewable energy. And expand the use of clean energy.

Iron flow batteries are made from abundant materials such as iron, salt and water, making them safe, low-cost and sustainable. Both ESS and Form Energy are representative companies of iron flow batteries.

Oregon-based ESS, whose batteries can store 4 to 12 hours of energy, claims to be able to be charged and discharged indefinitely without losing capacity. It launched its first grid-scale project in 2021.

Massachusetts-based Form Energy, which raised $240 million in 2021, has batteries that can store electricity for up to 100 hours, and its first installation will be at a one-megawatt pilot plant in Minnesota, which is expected to Completion in 2023.

Some analysts believe that the unit cost of a lithium-ion battery energy storage system with a continuous discharge time of 4 hours is relatively low, but in applications with a continuous discharge time of more than 4 hours, the cost of an iron flow battery energy storage system is relatively lower.

Form Energy said its batteries could end up costing as little as $20 per kilowatt-hour, even less than optimistic forecasts for lithium-ion batteries for decades to come.

In terms of industrial applications, Gaogong Energy Storage learned that ESS mainly has two battery energy storage products: the 400kWh Energy Warehouse battery energy storage system for commercial and industrial (C&I) customers, and the energy storage system for utility-scale applications. Energy Center battery energy storage system. The company expects to sell 40 to 50 Energy Warehouse battery storage systems this year.

Just recently, ESS said that it will deploy an iron flow battery energy storage system for the first time in Europe, and is expected to have local manufacturing capacity in Europe by 2025.

ESS expects to start production of the two battery energy storage products in continental Europe in 2024 and energy storage system power modules in continental Europe in 2025.

The company’s long-term clients include SoftBank Group’s clean energy arm SB Energy, Enel Green Power España and Chilean utility Edalaysen.

ESS previously cited a report issued by the Long Term Energy Storage Council (LDES) that 85 to 130 GWh of battery storage systems will need to be deployed around the world.

At present, the technical routes of long-term energy storage mainly include flow batteries, gravity energy storage and green hydrogen solutions. Among them, flow batteries are regarded as one of the important trends and have obvious advantages. In the past few years, this technical route mainly Mainly vanadium redox flow batteries.

According to the analysis, a large determinant of the feasibility of a flow battery is the system cost, which is closely related to the choice of electrolyte active materials. Historically, vanadium redox flow batteries have been the preferred choice due to their various attractive electrochemical properties, including relatively long lifetimes.

But with prices falling, lithium-ion batteries can now compete on cost with vanadium flow batteries. As the design of vanadium redox flow batteries brings cost advantages from “4 to 6 hours of continuous discharge time”, strategies for development to improve the economics of active materials are also evolving.

Flow batteries will compete with lithium-ion batteries for up to 69GWh by 2030 (46% of the total required capacity of 150GWh), according to the Energy Storage Grand Challenges report released by the U.S. Department of Energy. Peak demand and energy transfer are the most competitive applications of flow batteries. Iron-based flow batteries, developed to address the cost of vanadium flow batteries, could change that forecast.

It is worth noting that iron-based flow battery technology still has certain challenges, and its efficiency is usually very low, which means that a considerable part of the energy invested cannot be recovered. In addition, side reactions can also degrade the battery over time, which means that the technology still needs to be further matured and perfected before it can be applied on a large scale.