BHP looks to use 35-tonne blocks to store renewable energy for its WA operations


US-Swiss startup Energy Vault makes gravity energy storage solutions, similar to pumped hydro, only it lifts blocks to use surplus energy and lowers them to generate it. The long-duration solution, according to the company, is cheaper to build than pumped hydro projects and does not require drastic landscape reshaping.

It has signed a Memorandum of Understanding with resources giant BHP which will focus on using its storage systems at BHP operations as well as “exploring opportunities for new applications relevant to BHP’s business.”

This seems to be referencing the exploration of using waste materials to produce the Energy Vault composite blocks, include mining tailings and coal combustion residuals (coal ash), of which BHP probably has large stores it’s eager to rid itself of. Also posited was the idea of including fibreglass from decommissioned wind turbine blades to make the blocks.

Energy Vault’s storage durations start from 2 hours and continuing to 12 hours or more. There is zero degradation in the storage capacity of the raised composite blocks, which can remain in the raised position for unlimited periods of time, said Energy Vault.

For the startup, the agreement would provide a foot in the door into the Australian market.

How the EVx tower works

In August, Energy Vault secured US$100 million (AU$140 million) in Series C funding for its EVx tower, a six-arm crane tower designed to be charged by grid-scale renewable energy. It lifts large bricks using electric motors, thereby creating gravitational energy. When power needs to be discharged back to the grid, the bricks are lowered, harvesting the kinetic energy.

Energy Vault first commercial-scale deployment of the energy storage system happened in 2020, with the company launching its EVx platform this April.

The company said the EVx tower features 80-85% round-trip efficiency and over 35 years of technical life. It has a scalable modular design up to multiple gigawatt-hours in storage capacity.

The company said its technology can economically serve both higher power/shorter duration applications with ancillary services from 2 to 4 hours and can also scale to serve longer-duration requirements from 5 to 24 hours or more.

This content is protected by copyright and may not be reused. If you want to cooperate with us and would like to reuse some of our content, please contact: