Giant four-hour battery proposed next to Australia’s biggest operating pumped hydro plant

Plans to install a four-hour big battery next to the largest operating pumped hydro generator in Australia have been submitted for assessment under the federal government’s Environment Protection and Biodiversity Act.

Ace Power is seeking approval to build a 450 megawatt (MW), 1,800 megawatt-hour battery energy storage system (BESS) around 700 metres from the Tumut 3 Power Station, in what would be the first big battery to be built alongside the Snowy Hydro scheme in New South Wales.

The battery is planned for construction adjacent to Transgrid’s 330 kV Lower Tumut Switching Station, roughly 2.8km south of the township of Talbingo, on the traditional lands of the Ngarigo and Wolgalu Peoples.

A project fact sheet says the Talbingo Battery would be built on privately owned land and make “efficient use” of existing electrical infrastructure, including the Lower Tumut 330 kV switching station and nearby transmission lines.

The fact sheet says the big battery will assist in firming the electrical network and providing system services to the electrical network in NSW.

“In addition to absorbing and dispatching energy, batteries ensure the safe and reliable operation of electricity supply,” it says.

“They help contribute to lower energy prices, relieve curtailment and constraints in the network and ensure a stable and reliable supply of energy during extreme events like storms or equipment failures.”

The potential for combining pumped hydro and big batteries to provide “very cheap energy storage and cheap storage power” was recently detailed by ANU professor Andrew Blakers, in an article published on Renew Economy.

“For example, Snowy 2.0 (350 gigawatt-hours (GWh) of energy storage + 2.2 gigawatts (GW) of storage power) can be coupled with 5 GW of four-hour batteries located at grid strong-points,” Blakers writes.

“Now we have cheap high-power (7 GW) and very cheap large-scale energy storage (370 GWh).

“During calm and cloudy weather when energy prices go high, this hybrid system can meet a 7 GW load from 5pm to 9pm. For the following 20 hours, the PHES can trickle-recharge the batteries.

“It can do this for 12 days in a row before the PHES is empty, whereas a battery-only system would be empty after the first day.”

Plans for the Talbingo BESS are open for public comment via the federal government’s EPBC portal until June 17, and Ace Power says it also welcomes welcomes feedback through the community consultation process, which is currently underway.

It says that fire and bushfire have been highlighted as a key concern in consultations, so far, and the community wants to understand how this will be managed and how firefighting activities will be impacted in the event of a fire at the battery.

As the EPBC referral documents note, “there is a history of serious bushfires in the region, with instances occurring as recently as 2020.” There are also sections within the project area that are mapped as Category 1 bushfire prone land.

As well as the EPBC process, the Talbingo Battery project is currently preparing an Environmental Impact Statement (EIS) as part of the State Significant Development Approval application process with the NSW government.