Can Big Drums Beat the Network Blues?

Large batteries could be configured to unlock a key brake on the transition to renewable energy.

Australian renewable energy development company Edify Energy will receive $6.6 million in funding from the Australian Renewable Energy Agency (ARENA) to develop an advanced battery and inverter system capable of stabilizing the power grid.

Until now, this vital role has been played mainly by coal and gas generators.

Grid-forming batteries, which combine grid-scale battery storage systems with advanced inverter technology, offer a substitute for grid-stabilizing synchronous generation provided by fossil fuel-fired coal-fired power plants who are due to retire over the next decade.

Importantly, this is the first grid forming battery to receive the required grid connection approvals from the Australian Energy Market Operator (AEMO).

Power grid transmission lines, cables and devices are designed to operate within stable parameters. If these are exceeded, it can lead to breakdowns and serious damage.

As grid-scale lithium-ion batteries become more common, it is possible to equip them with advanced inverters so that the batteries can become one of the primary sources of system stability for the power grid.

Transmission lines in the Queensland network. Picture: Power Link.

By ensuring that there are enough sources of system stability, more renewable generators like wind and solar farms will be able to connect more seamlessly to the grid.

Additionally, if AEMO is able to rely on grid-forming batteries for system stability, it will be able to turn off synchronous generators during periods of high renewable energy generation, rather than forcing them to remain operational when they are not needed and are not profitable. .

And that’s where the Edify Energy project comes in.

Full potential

Located next to the 275MW Darlington Point Solar Farm in South West New South Wales, the ARENA-backed 25MW/50MWh battery will be one of the most advanced battery systems of the national electricity market.

ARENA funding enabled Edify to expand the project to a total of 150 MW / 300 MWh. The entire project will be equipped with advanced inverters to help future-proof the Darlington Point area as renewable energy generation continues to expand in South West New South Wales.

Designed and developed by Edify, the Tesla Megapack storage system will use grid-forming inverters that operate the battery to behave similarly to a synchronous generator during grid disturbances and help make the electrical system more resilient.

In this way, it will not only provide electricity, but also crucial system-strengthening services, essential to support the future adoption of more solar and wind energy.

The location of the Darlington Point solar farm is very suitable for testing this new inverter capability, as the local area has relatively low system power. This means that the project will provide a greater improvement in system power in the region, which will also connect more renewable energy in the region.

The current solution for low system resistance is to use expensive synchronous capacitors, but batteries offer a lower cost solution due to their ability to generate revenue.

The project location is ideal for demonstrating grid-forming capability due to the low system resistance in the region. Several solar farms in the region have had to install expensive synchronous condensers to ensure adequate system stability.

This project is expected to show that array-forming batteries can provide a more cost-effective solution to system stability issues, while providing new dispatchable generation capacity in the power system.

So, some questions that can be addressed include:

  • Can the battery support the system?
  • Can the battery provide a more efficient and cheaper solution than conventional technology?

Construction of the project began in June 2022. It is expected to be completed in stages during 2023.

Artist's impression of the Broken Hill Battery Storage System
Artist’s impression of the Broken Hill Battery. Picture: Fluency.

ARENA Acting CEO Chris Faris said large-scale batteries are now seen as more than just storage devices for the grid and will be used to their full potential.

“ARENA has worked with key stakeholders, including AEMO, to accelerate the development of the next generation of energy storage.

“To support the rapid transformation of our electrical system, large-scale batteries will need to evolve to do more than just store energy. They must be equipped with advanced inverters capable of providing essential grid stability services to ensure the system security, especially as synchronous generators retire and renewables provide a higher share of supply, which is why it is important to support and demonstrate projects like this, where batteries with advanced inverters can help provide critical stability services to the grid, says Faris.

Edify Energy Managing Director John Cole said, “In this case, we are using the combination of the dispatchable properties of batteries with a new vintage of network-forming inverter control systems.”

“With the widespread adoption of this technology, we will remove the last bastion of any reliance on the carbon-intensive generation fleet in place and help usher in a 100% renewable future with the confidence of an electric system. stable and reliable”

ARENA has previously funded four other projects to demonstrate advanced inverter functionality, including AGL’s Broken Hill Battery, Electranet’s ESCRI Battery, Hornsdale Power Reserve Extension and Transgrid’s Wallgrove Battery. .