Depends on what you call huge ?Larger than a Lithium battery of...

Depends on what you call huge ?
Larger than a Lithium battery of the same capacity, but for standing storage applications the slight size difference is far outweighed by the many advantages.

Here is an article on another VRB install by VSUN, which show's a battery and mentions the particular application.
Also from the article --->>
"With different properties to the dominant lithium-ion batteries, vanadium flow batteries are gaining traction worldwide for being safer, more scalable, longer-lasting and more reliable. Notably, vanadium flow batteries don’t degrade with cycling like lithium-ion options and are able to move electricity without generating heat. "