WA's second big $100M battery planned by Alinta for Wagerup

South West WA's power system may get two $100M big batteries to help handle rooftop solar growth with Alinta planning an investment at its Wagerup power station.

WA's second big $100M battery planned by Alinta for Wagerup


WA's second big battery is planned for Alinta Energy's power station in Wagerup and could equal the size of Synergy's $100 million-plus investment in Kwinana.

The WA Environmental Protection Authority yesterday published its approval for the "installation of a battery energy storage system (BESS), with a battery power output of 100 megawatts."

The system was described as modular, suggesting Alinta could install capacity in stages.

The system will cost about $100 million and be completed in the March quarter of 2023, according to a planning application to the Shire of Waroona lodged in December 2020. The battery will "improve the reliability of the electricity network and facilitate increased penetration of renewable energy."

In October 2020 WA's largest power generator Synergy announced plans to install a battery in Kwinana that could deliver power at a rate of 100MW and store 200MW-hours of energy. It was to be the second-largest in Australia.

WA plans $100M big battery to balance solar
A huge battery in Kwinana will help tame the chaos in the South-West WA power system caused by soaring output from rooftop solar panels and pave the way for more renewable energy.

A spokesperson for Energy Minister Bill Johnston said tender submissions for construction of the Big Battery at Kwinana Power Station closed today.

"Tender evaluation will take place over coming months, with the battery targeted to be operational towards the end of 2022,"the spokesperson said.

In the past six months the size of Synergy's "Big Battery" has been surpassed by several announcements in the eastern states. The largest is a 500MW/450MW-hours BESS on Sydney's outskirts on the site of a disused coal-fired power station.

The EPA also approved an increase in Wagerup's capacity from 350MW to 450MW, allowing the two gas turbines and battery to all export at maximum capacity at the same time. The approval document did not specify the amount of battery storage.

Synergy plans to store energy in its Kwinana battery in the middle of the day when rooftop solar panel output peaks and feed it back to the grid in the early evening.

Alinta could do the same and further help reduce the so-called duck curve that, if untamed, threatens the power system's stability by pushing minimum demand too low.

Forecast growth in the duck curve on the South West Interconnected System for 2018 to 2028 by AEMO.
Forecast growth in the duck curve on the South West Interconnected System. Source: AEMO 2019.

Both batteries could also participate in the Essential System Services market to be introduced on the South West grid that will reward facilities that help stabilise the frequency of the power system.

The Wagerup facility is adjacent to Alcoa's alumina refinery but the two facilities are separate.

The 380MW Wagerup power station was the seventh-largest generator on the South West grid in the 12 months to June 2020, according to Clean Energy Regulator data.

Alinta has a second gas-fired power station in the South West near Alcoa's Pinjarra refinery. It is a cogeneration plant that supplies steam to Alcoa as well as 285MW of power to the grid.

Alinta began life as the State-owned supplier of gas to WA homes and was privatised in 1998.

It remains a domestic gas retailer in WA, competing with Kleenheat, AGL and others.

With little public profile, it has become a significant player in WA power.

The Chinese-owned company runs two gas-fired power stations in the Pilbara: a 178MW Newman facility and 210MW of capacity in Port Hedland.

The Newman station that powers the Roy Hill mine incorporates a 30MW battery.

Alinta also owns almost 12 per cent of the Goldfields Gas Pipeline and manages and part-owns the 214MW Yandin wind farm that started operating in 2020.

In 2018 Alinta owner, Chow Tai Fook Enterprises Limited, bought the 1100MW Loy Yang B coal-fired power station in Victoria.

Boiling Cold does not know if Alinta is fully committed to the Wagerup battery investment at this stage or if more approvals are required.

Alinta Energy did not respond by deadline to questions from Boiling Cold.

Updates and Corrections:

7 April 2021 4:40 PM: Comments from the Energy Minister's spokesperson added.

7 April 2021 10:00 PM: Cost and schedule from planning application added.

14 April 2021: Removed incorrect statement that the Wagerup power station was a cogeneration plant that supplied steam to Alcoa.  

Main image: Wagerup power station. Source: Steven Bradley, CC BY-SA 3.0, via Wikimedia Commons.