Happy birthday, SA’s big battery, and many happy returns (of your recyclable parts)


Aleesha Rodriguez, Queensland University of Technology

A year ago today, Tesla’s big battery in South Australia began dispatching power to the state’s grid, one day ahead of schedule. By most accounts, the world’s largest lithium-ion battery has been a remarkable success. But there are some concerns that have so far escaped scrutiny.

The big battery (or the Hornsdale Power Reserve, to use its official name) was born of a Twitter wager between entrepreneurs Mike Cannon-Brookes and Elon Musk, with the latter offering to build a functioning battery in “100 days or it’s free”.

Musk succeeded, and so too has the battery in smoothing the daily operation of South Australia’s energy grid and helping to avert blackouts.




Read more:
A month in, Tesla’s SA battery is surpassing expectations


The battery has also been a financial success. It earned A$23.8 million in the first half of 2018, by selling stored electricity and other grid-stabilising services.

These successes have spurred further big battery uptake in Australia, while the global industry is forecast to attract US$620 billion in investments by 2040. It’s clear that big batteries will play a big role in our energy future.

But not every aspect of Tesla’s big battery earns a big tick. The battery’s own credentials aren’t particularly “green”, and by making people feel good about the energy they consume over summer, it arguably sustains an unhealthy appetite for energy consumption.

The problem of lithium-ion batteries

The Hornsdale Power Reserve is made up of hundreds of Tesla Powerpacks, each containing 16 “battery pods” similar to the ones in Tesla’s Model S vehicle. Each battery pod houses thousands of small lithium-ion cells – the same ones that you might find in a hand-held device like a torch.

The growing demand for lithium-ion batteries has a range of environmental impacts. Not least of these is the issue of how best to recycle them, which presents significant opportunities and challenges.

The Hornsdale Power Reserve claims that when the batteries stop working (in about 15 years), Tesla will recycle all of them at its Gigafactory in Nevada, recovering up to 60% of the materials.

It’s important that Tesla is held account to the above claim. A CSIRO report found that in 2016, only 2% of lithium-ion batteries were collected in Australia to be recycled offshore.

However, lithium-ion batteries aren’t the only option. Australia is leading the way in developing more sustainable alternative batteries. There are also other innovative ways to store energy, such as by harnessing the gravitational energy stored in giant hanging bricks.




Read more:
Charging ahead: how Australia is innovating in battery technology


Solving symptoms, not problems

Tesla’s big battery was introduced at a time when the energy debate was fixated on South Australia’s energy “crisis” and a need for “energy security”. After a succession of severe weather events and blackouts, the state’s renewable energy agenda was under fire and there was pressure on the government to take action.

On February 8, 2017, high temperatures contributed to high electricity demand and South Australia experienced yet another widespread blackout. But this time it was caused by the common practice of “load-shedding”, in which power is deliberately cut to sections of the grid to prevent it being overwhelmed.

A month later, Cannon-Brookes (who recently reclaimed the term “fair dinkum power” from Prime Minister Scott Morrison) coordinated “policy by tweet” and helped prompt Tesla’s battery-building partnership with the SA government.




Read more:
A year since the SA blackout, who’s winning the high-wattage power play?


Since the battery’s inception the theme of “summer” (a euphemism for high electricity demand) has followed its reports in media.

The combination of extreme heat and high demand is very challenging for an electricity distribution system. Big batteries can undoubtedly help smooth this peak demand. But that’s only solving a symptom of the deeper problem – namely, excessive electricity demand.

Time to talk about energy demand

These concerns are most likely not addressed in the national conversation because of the urgency to move away from fossil fuels and, as such, a desire to keep big batteries in a positive light.

But as we continue to adopt renewable energy technologies, we need to embrace a new relationship with energy. By avoiding these concerns we only prolong the very problems that have led us to a changed climate and arguably, make us ill-prepared for our renewable energy future.

The good news is that the big battery industry is just kicking off. That means now is the time to talk about what type of big batteries we want in the future, to review our expectations of energy supply, and to embrace more sustainable demand.The Conversation

Aleesha Rodriguez, Phd Student, Digital Media Research Centre, Queensland University of Technology

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Yes, SA’s battery is a massive battery, but it can do much more besides


Dylan McConnell, University of Melbourne

Last Friday, the “world’s largest” lithium-ion battery was officially opened in South Australia. Tesla’s much anticipated “mega-battery” made the “100 days or it’s free” deadline, after a week of testing and commissioning.

Unsurprisingly, the project has attracted a lot of attention, both in Australia and abroad. This is largely courtesy of the high profile Tesla chief executive Elon Musk, not to mention the series of Twitter exchanges that sparked off the project in the first place.

Many are now watching on in anticipation to see what impact the battery has on the SA electricity market, and whether it could be a game-changer nationally.

The Hornsdale Power Reserve

The “mega battery” complex is officially called the Hornsdale Power Reserve. It sits alongside the Hornsdale Wind Farm and has been constructed in partnership with the SA government and Neoen, the French renewable energy company that owns the wind farm.

The battery has a total generation capacity of 100 megawatts, and 129 megawatt-hours of energy storage. This has been decribed as “capable of powering 50,000 homes”, providing 1 hour and 18 minutes of storage or, more controversially, 2.5 minutes of storage.

At first blush, some of these numbers might sound reasonable. But they don’t actually reflect a major role the battery will play, nor the physical capability of the battery itself.

What can the battery do?

The battery complex can be thought of as two systems. First there is a component with 70MW of output capacity that has been contracted to the SA government. This is reported to provide grid stability and system security, and designed only to have about 10 minutes of storage.

The second part could be thought of as having 30MW of output capacity, but 3-4 hours of storage. Even though this component has a smaller capacity (MW), it has much more storage (MWh) and can provide energy for much longer. This component will participate in the competitive part of the market, and should firm up the wind power produced by the wind farm.


Read more: Australia’s electricity market is not agile and innovative enough to keep up


In addition, the incredible flexibility of the battery means that it is well suited to participate in the Frequency Control Ancillary Service market. More on that below.

The figure below illustrates just how flexible the battery actually is. In the space of four seconds, the battery is capable of going from zero to 30MW (and vice versa). In fact it is likely much faster than that (at the millisecond scale), but the data available is only at 4-second resolution.

Hornsdale Power Reserve demonstrating its flexibility last week. The output increased from zero to 30MW (full output) in less than 4 seconds.
Author provided (data from AEMO)

Frequency Control and Ancillary Service Market

The Frequency Control and Ancillary Service (FCAS) market is less known and understood than the energy market. In fact it is wrong to talk of a single FCAS market – there are actually eight distinct markets.

The role of these markets is essentially twofold. First, they provide contingency reserves in case of a major disturbance, such as a large coal generation unit tripping off. The services provide a rapid response to a sudden fall (or rise) in grid frequency.

At the moment, these contingency services operate on three different timescales: 6 seconds, 60 seconds, and 5 minutes. Generators that offer these services must be able to raise (or reduce) their output to respond to an incident within these time frames.

The Hornsdale Power Reserve is more than capable of participating in these six markets (raising and lowering services for the three time intervals shown in the illustration above).

The final two markets are known as regulation services (again, as both a raise and lower). For this service, the Australian energy market operator (AEMO) issues dispatch instructions on a fine timescale (4 seconds) to “regulate” the frequency and keep supply and demand in balance.

The future: fast frequency response?

Large synchronous generators (such as coal plants) have traditionally provided frequency control, (through the FCAS markets), and another service, inertia – essentially for free. As these power plants leave the system, there maybe a need for another service to maintain power system security.

One such service is so-called “fast frequency response” (FFR). While not a a direct replacement, it can reduce the need for physical inertia. This is conceptually similar to the contingency services described above, but might occur at the timescale of tens to hundreds of milliseconds, rather than 6 seconds.


Read more: Baffled by baseload? Dumbfounded by dispatchables? Here’s a glossary of the energy debate


The Australian Energy Market Commission is currently going through the process of potentially introducing a fast frequency response market. In the meantime, obligations on transmission companies are expected to ensure a minimum amount of inertia or similar services (such as fast frequency response).

I suspect that the 70MW portion of the new Tesla battery is designed to provide exactly this fast frequency response.

Size matters but role matters more

The South Australian battery is truly a historic moment for both South Australia, and for Australia’s future energy security.

The ConversationWhile the size, of the battery might be decried as being small in the context of the National Energy Market, it is important to remember its capabilities and role. It may well be a game changer, by delivering services not previously provided by wind and solar PV.

Dylan McConnell, Researcher at the Australian German Climate and Energy College, University of Melbourne

This article was originally published on The Conversation. Read the original article.