Goodbye batteries, hello brick building

A technology involving a modified construction crane, an electric motor and 35-tonne bricks is providing long-duration energy storage. Energy Vault is a long-term power storage that aims to address the problem of integrating intermittent energy sources, such as solar and wind, with the national grid.

Explaining the technology, Energy Vault Chief Commercial Officer Merrick Kerr said, “The Energy Vault system takes the simple principles of pumped hydro but, instead of using water, we use low-cost 35-tonne bricks.

“When you want to store the energy, you simply use a modified construction crane and an electric motor to lift 35-tonne bricks from a low position to build a tall, free-standing tower. The energy is then stored as potential energy in the elevation gain of the bricks. “When you want the power back, you simply lower the bricks back to their low position and the motor that was used to lift them now becomes a generator,” he explained.

Kerr said that Energy Vault’s primary purpose is to provide a long-term storage solution that helps expand the capacity of the grid.

“[Energy Vault] is designed to provide long-duration storage; it was designed to allow a much greater quantum of intermittent renewable resources to be attached to a grid, and to provide the potential for off-grid, mini-grid and micro-grid solutions that can be run on 100% renewable energy,” he said.

“Our technology can respond in milliseconds and ramps at over 33% per second, so it can provide the ancillary services currently provided by chemical batteries. If you require long-duration and short-duration [storage], then you can dispense with the chemical batteries and just use our solution.”

Australia has ample solar and wind resources, but as sustainable energy companies accelerate efforts to harness them, it has become apparent that the current grid is not well suited to intermittent energy sources.

Kerr commented that, “We have a levelised cost of storage that in good sun areas allows us to combine with PV and deliver very close to 24 by 7 by 365 solar energy for less than the cost of diesel generation. We believe our technology offers an excellent opportunity for Australia to accelerate its wind and solar program again, and this time without the negative impacts on the grid.”

As an added bonus, the bricks used by Energy Vault are made out of waste materials that would otherwise go to landfill, such as bottom ash from coal plants, mine tailings and contaminated soil. Kerr said, “In these circumstances we get a real win-win as you clean up an environmental problem and provide much-needed energy storage.”

Merrick Kerr will discuss Energy Vault’s storage technology at the Australian Energy Storage Conference & Exhibition 2019 on 13–14 June at the International Convention Centre in Sydney.

For more information or to register, visit australianenergystorage.com.au.

Image courtesy of Australian Energy Storage Conference & Exhibition.