South Korea's Hyundai Electric & Energy Systems will soon complete a massive lithium ion battery in the industrial city of Ulsan.

When it goes live in three months, Hyundai's 150-megawatt system will overtake Tesla's 100-megawatt facility in South Australia as the world's largest industrial energy storage system, Independent.ie reported. Sorry, Elon Musk.

It's an exciting—albeit geeky—race to help the planet wean off environmentally harmful fossil fuels. That's because if we want to accelerate the world's renewable energy transition, we'll have to modernize the energy grid and much of that depends on energy storage technology.

Tesla famously built its ginormous battery within 100 days after Australian billionaire Mike Cannon-Brookes dared Musk to help fix the South Australian's electricity woes. The system, which is connected to Neoen's Hornsdale wind farm, has exceeded expectations after switching on about a year ago. The lightning-fast system has saved about $40 million in grid stabilization costs, prevented blackouts and helped restore confidence in the state's energy resources, the Australian Financial Review noted.

Hyundai's $45 million battery is being built for the metal smelting company KoreaZinc, which intends to be energy self-sufficient and wants to reduce electricity costs, according to Climate Action. The company estimates it will save almost $60 million in electricity expenses over the next three years once the facility is built. KoreaZinc is also complying with the South Korean government's larger efforts to boost renewables and mitigate air pollution, the publication added.

These large-scale projects are enabled by less expensive battery prices, with prices dropping by almost half since 2014, according to Bloomberg.

Other entrepreneurs are joining in the big battery race, including billionaire Sanjeev Gupta's SIMEC ZEN Energy, which plans to build a 120-megawatt battery near Adelaide. Tesla is also vying to build another giant Powerpack system in Colorado for Xcel Energy Inc., an electric utility operating in eight Western and Midwestern states.

Bloomberg New Energy Finance (BNEF) estimated that developers announced 1,650 megawatts per hour of new lithium-ion battery projects in 2017, four times the amount for all of 2016.

"Musk has set a benchmark on how quickly you can install and commission a battery of this size," Ali Asghar, a BNEF senior associate, said in a Bloomberg interview.

Falling costs are "making them a compelling mainstream option for energy-storage applications in many areas around the world, and projects even bigger than Tesla's are now under construction."