Gravity storage pioneer to build two batteries next to Australia’s biggest solar farm

The US-based Energy Vault, which has made headlines across the world with its so-called gravity storage technology, has been awarded contracts to build two big batteries at the site of Australia’s biggest solar farm.

The deal was announced jointly by Energy Vault and Acen Renewables, which is building the New England solar farm in NSW, which will be sized at 720 MW when the 320 MW second stage is finished and added to the already complete 400 MW first stage.

Acen has previously flagged its intention to build a 200 MW, 400 MWh battery at the site, and it appears to have decided to deliver that capacity but with two distinct installations, one a 50 MW, 100 MWh battery and the other a 150 MW, 300 MWh battery.

According to the two companies, construction will begin in the second half of 2024, with commercial operations expected in 2025, presumably for the smaller project, and in 2026.

Energy Vault says the batteries will be charged and discharged on a daily basis and designed to dispatch stored renewable energy at peak consumption hours to help meet high demand as the state reduces its reliance on its ageing coal fleet.

“These deployments, and the tight timelines under which they will be delivered, stand as a testament to Energy Vault’s commitment to a customer-centric approach to energy storage as well as evidence of the growing global demand for reliable and effective energy storage solutions,” said Energy Vault chairman and CEO Robert Piconi.

“We see today’s agreement as just the first step in a long and fruitful relationship with Acen and their renewable power generation projects moving forward.”

Energy Vault’s gravity storage technology has been greeted with a mixture of curiosity and skepticism, and questions over the efficiency of using renewable power to lift and then lower large weights, operating in the same way as pumped hydro but with solid mass.

Still, Energy Vault announced earlier this week that is has commissioned its first large scale gravity storage project, a 25 MW, 100 MWh facility in Rudong, China.

It has also turned its focus to more conventional battery storage projects, and recently completed a 220 MW, 440 MWh battery built for NV Energy at the site of a decommissioned coal fired generator in Nevada.

In late 2022, Energy Vault announced plans to build a 250 MW, two hour battery near Wangaratta in Victoria at a site known as Meadow Creek, but nothing has been heard of that project since. We have reached out to the company to ask for an update.

t has also struck MoUs with some big names in the industry, such as BHP, and also a potential “multi gigawatt hour” storage proposal with Ark Energy for use with the Sun Metals zinc refinery in Queensland.

• However, in its first quarter results released earlier this week Energy Vault revealed first quarter revenue of just $US7.8 million and a net loss of $21.1 million, which had reduced from a loss of $US31.2 million in the same period a year earlier due to lower operating expenses.

Energy Vault has developed a suite of integrated battery solutions its dubs as “B-Vault”, and these will be coupled with Siemens S120 inverter, which enables advanced grid support functionalities such as voltage and frequency ride-through, grid support during disturbances, and reactive power control.

Acen Australia managing director David Pollington said Energy Vault was selected for the New England projects due to its impressive track record.

“Energy Vault’s ability to work with our Siemens S120 converters will be particularly valuable as we optimize our battery storage systems for maximum efficiency and impact,” he said.

Acen’s New England solar project, located near the town of Uralla, last year won a 20-year Long Term Energy Service Agreement (LTESA) in the first renewable and storage auction held by the NSW government. The contract effectively minimises the risk for project developers and protects the facility from sustained low prices.