New York has a reputation as the city that never sleeps. But it does use much less electricity after dark — and its utilities charge a lower price for power then.
On top of a Manhattan skyscraper is a car-sized battery that charges itself at night, when most of the building is empty and electricity costs less. When office workers arrive the next morning — and the electricity price rises — the battery discharges to power the building.
The mega-battery was produced by American Vanadium (don't let the name fool you, it's actually Canadian, run out of Vancouver). And its technology has the potential to transform electrical grids, along with our ability to make use of green energy such as wind and solar power.