Powering down a misinterpretation of battery storage

^{By Renee Davidson}

Political lobby group Advance Australia has misinterpreted battery storage data for Asia to suggest that Australia cannot rely on battery storage to meet the nation’s energy needs.

In a Facebook post, the group, which has 90,000 followers, wrote: “Energy Minister Chris Bowen claims battery storage is the key to our renewable-induced energy woes. Reality disagrees, just look at Asia, they have just 31 seconds of battery storage.” 

The post includes a chart under the headline: “Batteries won’t save Asia. Asia has batteries able to supply just 31 seconds of average electricity consumption now and about 10 minutes in 2030.” 

RMIT FactLab found no evidence that Mr Bowen claimed “battery storage is the key to our renewable-induced energy woes”, and experts consulted by FactLab dismissed the post as a “misinterpretation of the facts”.

A reverse image search reveals the chart used in the post was first published on Twitter by Dr Bjorn Lomborg, a sceptical environmentalist and author with more than 127,000 followers.  

In his tweet Dr Lomborg wrote: “We're told solar and wind future. But when wind is not blowing and sun not shining? Batteries! Yet. Asia uses 25GWh/minute and has 13GWh of battery storage: enough for just 31 seconds. 2030: 9m:55s. After that, need 100% backup, mostly fossil fuels.”

A renewable energy grid supplies electricity through a combination of renewable energies (wind and solar power) and storage. 

Professor Lachlan Blackhall, Entrepreneurial Fellow and Head of the Battery Storage and Grid Integration Program at the Australian National University, told RMIT FactLab that the Advance Australia post effectively claimed: if all the energy in Asia’s grids had to be supplied from available battery storage, it would last just 31 seconds.

The post, which has been shared 300 times, amounted to a “misinterpretation of the facts” he said.

“The claim is misleading because battery storage is not intended to provide full backup. We would never power the entire grid from batteries and within this context, calculating the duration of battery backup is misleading,” he said.

Professor Blackhall said the claim ignored the fact that there are other forms of storage in the electricity grid, predominantly pumped hydropower, which provides a much longer duration of energy storage and accounts for more than 97 per cent of the world’s electricity storage. 

“So a far better calculation, if you were thinking about total energy storage, would be to calculate pumped hydro alongside battery storage,” he said. 

Pumped hydro is a form of energy storage that works by linking two water reservoirs at different elevations. During periods of high energy demand, water is released into the lower reservoir through turbines, which generates electricity. During off-peak times, the water is pumped back into the upper reservoir.

According to the International Energy Agency, there is significant pumped hydro development across Asia, with China and India among leading countries globally in pumped hydropower storage capability. 

Professor Iain MacGill, Joint Director of UNSW’s Centre for Energy and Environmental Markets, told RMIT FactLab it was “not surprising” that batteries cannot supply energy to the whole grid. 

“Battery deployment is growing rapidly from a small base, so the actual energy storage available in batteries is very modest compared to total generation,” he said.

He said most of the current energy storage in the Australian National Energy Market was pumped hydro, which is set to increase via Snowy 2.0. 

“I don’t think anyone claims that batteries alone will successfully address the challenges of integrating high penetrations of wind and solar,” he said. “Certainly not the Federal Government or the Australian Energy Market Operator [AEMO].” 

He said this was because there were a range of other mechanisms to manage variations in solar and wind, in addition to energy storage, including “transmission by aggregating wind and solar across geographical regions, flexible demand, flexible conventional generation including gas plants, distributed resources, as well as storage via pumped hydro and batteries.”

 According to AEMO’s June 2022 Integrated System Plan, these mechanisms will play a key role in the Australian national energy market’s transition from fossil fuels to renewables: “Investment in low-cost renewable energy, firming resources and essential transmission remains the best strategy to deliver affordable and reliable energy.”

ANU’s Professor Blackhall told RMIT FactLab that batteries in the power system also provided a “balancing” function to ensure that energy reliability is maintained, a key point that was omitted from Advance Australia’s Facebook post. 

The capability of batteries to “balance” the grid means they can provide a very quick response to any energy imbalance in the power grid, which is particularly valuable when there is a mismatch between supply and demand or following a large disturbance.  

The Australian Renewable Energy Agency’s website notes that “unlike many forms of energy storage, batteries are particularly valuable because they provide flexibility. They can respond faster than other energy storage or generation technologies, and help maintain grid stability by turning on and off in fractions of a second.”

While grid operators traditionally rely on fossil fuels to fulfil this balancing function, the AEMO forecasts that as technology improves and with sufficient batteries installed, batteries can play “an even greater role” in the electricity system than coal fired power plants, including the delivery of more secure services to the power system. 

RMIT FactLab found no evidence that Mr Bowen claimed batteries were “key” to Australia’s renewable energy woes. Instead, he has argued that “battery storage is the future” and that it is up to the states to decide how they want to provide backup energy generation as long as they meet the 2030 target.

In a joint press conference with Prime Minister Anthony Albanese in June 2022, Minister Bowen committed to provide a framework for renewable energy for storage and transmission, saying there was insufficient investment in storage.

“Yes, you can say the wind doesn't always blow and the sun doesn't always shine. The rain doesn't always fall either but we can store the water and we can store renewable energy if we have the investment. That investment has been lacking for the last decade. That is the problem.”