* Top Japanese coal, LNG buyer in green push
* Big growth opportunity for utility scale batteries in Asia
* Fluence to supply batteries for 3 Australian solar farms
MELBOURNE, May 29 (Reuters) - Japan's JERA, a U.S.-German joint venture and an Australian firm have teamed up to develop battery projects in the Asia-Pacific, including the world's biggest, targeting a market expected to be worth several billion dollars by 2022.
The move marks a big green push for JERA, a joint venture between Tokyo Electric Power Co and Chubu Electric Power Co that is the world's top buyer of liquefied natural gas (LNG) and one of the world's biggest coal traders.
The plan is for JERA to fund energy storage projects with Australian renewable power developer Lyon Group, while Fluence - a joint venture between U.S. power company AES Corp and Germany's Siemens AG - provides battery technology.
The companies will focus first on batteries for three solar farms, together expected to cost up to A$1.5 billion ($1.1 billion), that Lyon Group plans to build in Australia.
Globally, demand for utility-scale batteries is expected to rise to 28 gigawatts, worth more than $15 billion, by 2022, up from 2 GW committed by electricity providers in 2017, according to estimates from Fluence and others.
The batteries play a vital role in maintaining stability on the grid by balancing supply and demand for a few minutes to a few hours when wind and solar energy fluctuate, and can eliminate the need for expensive power plants that might be used for only a few hours a day.
Fluence sees opportunities in Asia in Japan, China, Korea and India, but for the moment sees Australia growing the fastest as the country copes with rapid growth in renewable energy, soaring power prices and an ageing grid.
"That market has huge potential to grow very, very quickly," Fluence's Asia Pacific market director, Mark Leslie, told Reuters.
Lyon's Riverland project in South Australia would be the world's biggest battery, with 400 megawatt hours (MWh) of storage, eclipsing the current largest, Tesla's 129 MWh battery, also in South Australia.
Lyon said construction is expected to begin on all three of its projects within months. Riverland and the Nowingi project in the state of Victoria need offers to connect to the grid before construction can begin.
A smaller project, Cape York, in the state of Queensland already has development approval and an offer to connect to the grid.
"There are many markets beyond Australia where big batteries can provide substantial value in terms of network strength and dispatchable capacity," Lyon Group Chairman David Green said in a statement.
$1 = 1.3221 Australian dollars Reporting by Sonali Paul; additional reporting by Yuka Obayashi in Tokyo; editing by Richard Pullin