Supporting a net zero future with long duration battery storage technology

As more clean energy assets appear, the ability to store intermittent outputs is becoming increasingly critical. Decarbonising the national electricity grid by 2030 is a pivotal part of the UK Government’s energy policy and a crucial step towards achieving net zero. Since the new Government has come into force, there’s been progress concerning onshore wind and solar energy, and a significant expansion of offshore wind via the recent CfD auction. All these energy sources are essential for delivering a cleaner grid, but increasing renewables in an isolated manner isn’t enough.

The International Energy Agency (IEA) forecasts that to support climate summit pledges of tripling global renewable energy capacity, energy storage will also need to increase sixfold. Furthermore, it’s not only the scale of storage needed but a required infrastructure evolution. Currently, most grid-scale storage projects have a duration of between 2 and 4 hours, which isn’t sufficient to achieve the needs of a fully renewable grid.

Established in 2011, ESS builds iron flow batteries specifically for long-duration energy storage. Flow batteries are built to manage deep, regular charge and discharge cycles over multiple years with little deterioration. This is something lithium-ion products are not well suited for. LDES flow batteries are capable of a duration between 6 and 12 hours, operating in a nearly continuous state of charge or discharge.

LDES technologies work on non-lithium battery chemistries and can store excess renewable energy during peak generation, supplying the grid during periods of peak demand. IFBs can maintain their capacity over thousands of cycles without being vulnerable to degradation.
Flow batteries provide a much smaller proportion of energy density compared to lithium but with an extended lifecycle, a lower cost and abundance making them an ideal option for the increasing stationary storage market.

One of the largest businesses in the flow battery space, ESS confirmed plans to triple production after a significant investment from the US Bank. ESB manufactures iron flow batteries for long-duration energy storage. For example, iron flow technology at the Schiphol airport in Amsterdam has been used for plans to electrify ground operations, eliminating diesel ground power units and replacing them with cleaner electric units. The transition will support the airport in reducing carbon emissions and air pollution, helping with the airport’s goal of being net zero by 2030.

While renewables could potentially meet nearly 90% of electricity demand during peak generation periods, their intermittency means that the national grid is very reliant on gas-powered facilities for backup. Over the last year, gas contributed 30% towards grid power, with renewables at around 40% and a combination of nuclear and biomass making up the rest. To completely decarbonise the grid, gas generation needs to be removed, and many industry experts believe flow batteries are the chosen technology to enable this.

Flow battery technology is in a strong power position in today’s stationary storage demands. For future energy requirements, new chemistries are being worked on, and these could completely transform electricity storage. German company Theion is one leading in market developments. The patented sulphur-crystal battery promises the potential to triple current battery energy density at a fraction of the cost and a third of the carbon footprint. The technology consists of a cathode shaped with sulphur crystals. Its new tech centre on the edge of Berlin has enabled it to expand production and the delivery of samples to customers. The goal is to generate the first phase of their battery technology by 2027, which will deliver more than twice the energy density of the latest batteries on the market.

Whether it’s flow batteries or new technologies like crystal sulphur, LCOS will play an important role in shaping the future of our grid. Reducing the storage costs, especially with intraday storage, is critical to supporting decarbonised electricity, displacing gas-powered facilities that many grids still depend on.