Battery in a drum rolled out
That's enough to power a computer workstation for 2 or 3 days, or to recharge a cell phone almost indefinitely, according to Younicos, the German company that invented the pack.
The mobile energy storage unit, called Yill, is a couple of feet in diameter, about the size of a small bass drum, with a handle and wheels. It recharges in about four hours in a 220-volt electric outlet.
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Tornadoes and More: What Spring Can Bring to the Power Grid
WASHINGTON - The storm and tornado outbreak that recently barreled through the US Midwest, South and Mid-Atlantic was a devastating reminder of how much danger spring can deliver, despite it being the “milder” season compared to summer and winter.
Danger season is approaching, and the country is starting to see the impacts.
The event killed at least 32 people across seven states. The National Weather Service is still tallying up the number of confirmed tornadoes, which has already passed 100. Communities coping with tragedy are assessing the damage, which so far includes at least 72 destroyed homes in one Tennessee county…