Tesla is building the world’s largest lithium-ion battery in South Australia — an installation 60% larger than any other large-scale battery energy storage system on the planet.

In partnership with the SA government and French renewables company Neoen, alongside the third stage of the Hornsdale Wind Farm, the PowerPack battery farm will top 100 megawatts of capacity and provide 129 megawatt-hours of energy generation to the region — load balancing the state’s renewable energy generation and allowing emergency back-up power if a shortfall in energy production is predicted.

The battery pack’s 100MW/129MWh capacity will top the world in terms of its size, solidly beating out the world’s current largest installation — a 80 megawatt-hour substation at Mira Loma in Ontario, California also built using Tesla batteries. The 129MWh project in SA will also use Tesla’s PowerPack 2 commercial/utility-grade battery systems, and will be 60 per cent larger than the California installation, with the capacity to power 4000 homes in the region for an entire day in case of blackout. It will be installed at the Hornsdale Wind Farm, a string of wind turbines stretching 8km and 24km north of Jamestown in South Australia.

The batteries will keep the lights on in South Australia, in a time where the state has struggled with reliable energy generation and suffered from a statewide blackout caused by a 50-year storm. Tesla has detailed its planned development in a blog post: “Tesla Powerpack will charge using renewable energy from the Hornsdale Wind Farm and then deliver electricity during peak hours to help maintain the reliable operation of South Australia’s electrical infrastructure. The Tesla Powerpack system will further transform the state’s movement towards renewable energy and see an advancement of a resilient and modern grid.

“Upon completion by December 2017, this system will be the largest lithium-ion battery storage project in the world and will provide enough power for more than 30,000 homes, approximately equal to the amount of homes that lost power during the blackout period.”

Tesla CEO Elon Musk famously promised that Tesla would get a battery system installed and up and running within 100 days of contract signature or it would be free, and SA’s government has taken him up on that — from the signature of the grid interconnection agreement, Tesla will have a little over three months to set up the PowerPack substation. SolarCity co-founder and cousin of Musk, Lyndon Rive, previously said at an event in SA that between 100 and 300 megawatts of storage would solve South Australia’s energy issues, which included a widespread blackout in the state in September of last year. Other bidders included Australia’s Carnegie Clean Energy.

The consortium of Tesla and Neoen will be known as the Hornsdale Power Reserve, with the company name registered with ASIC six weeks ago. The Power Reserve will be the largest renewable generator in the state as well as home to the largest lithium ion battery in the world. Neoen deputy CEO Romain Desrousseaux believes that it will be a watershed moment for batteries and renewables in Australia and around the world: “South Australian customers will be the first to benefit from this technology which will demonstrate that large-scale battery storage is both possible and now, commercially viable. Together, the South Australian Government, Neoen and Tesla will demonstrate that renewables can provide dependable, distributable power that will turn a new page in Australia’s energy future.”

This move is one of the first in South Australia’s $550m plan announced in March to secure its own means of energy production — a move that enraged the federal government. The total dollar cost of the installation has not been disclosed.

According to the South Australian government, Tesla and Neoen’s proposal was “the best value for money” of the 90 responses it received. Tesla has succeed in driving down the cost of lithium-ion batteries significantly — by over 30%, according to internal figures — since the company was founded with the construction of its Gigafactory in Nevada, soon to celebrate its first year of production.

At roughly five PowerPacks per MWh of energy generation, South Australia’s Tesla battery setup will comprise around approximately 640 PowerPack towers — each containing 16 individual battery pods that balance charge. The 129MWh of batteries to be installed at Hornsdale is roughly equivalent to the capacity installed into Tesla’s new electric cars during five days of Model S and Model X production at its plant in Fremont, California. Think 1200 cars as a battery.

Being a failover system in case of energy shortages in the region, the Tesla battery will provide emergency power — at least for a short time, in the context of South Australia’s power demands — and has the side benefit of lowering the chance of brownout events. Horndale already exports its excess energy production into the national grid, and is part of an AEMO trial into demonstrating that wind power can supply a baseload level of energy, known as frequency control and ancillary services or FCAS, to compete with traditional baseload sources like coal and gas.

South Australian premier Jay Weatherill is understandably chuffed: “South Australia has been leading the nation in renewable energy – now we are leading the world in battery storage. I’m thrilled with the selection of Neoen and Tesla, whose experience and world-leadership in energy security and renewables will help South Australia take charge of its own energy future. Battery storage is the future of our national energy market, and the eyes of the world will be following our leadership in this space. This historic agreement does more than bring a global energy giant in Tesla to South Australia, it will also have some significant economic spin-offs.”

The third partner in the Hornsdale renewable and battery consortium, French company Neoen, is fast-tracking the development of renewable power sources across Australia and is aiming for 1GW in wind and solar before 2020, including the third 109MW stage of the 315MW Hornsdale Wind Farm that the Tesla PowerPack will be installed alongside. Neoen was one of 5 shortlisted responses to SA’s wind tender, and the companies will work together to deliver the project by December 1.

The partnership between Tesla, Neoen and the SA government also extends further than the initial battery energy storage and Hornsdale project — without elaborating on any further detail, the state’s government said that “other investments” with the partners would be announced in the future. The Finkel Review into Australia’s energy networks recommended background wind power with battery storage, and also recommended that incentives be made available to consumers that invest in batteries and solar for their own houses and businesses.

Read more at Gizmodo Australia.

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