The 16” has a 100wh battery, so it needs 100w of power to charge 50% in 30 minutes (their “fast charging”). Add in 20w to keep the laptop running at the same ti

The 16” has a 100wh battery, so it needs 100w of power to charge 50% in 30 minutes (their “fast charging”). Add in 20w to keep the laptop running at the same time, and some conversion losses, and a 140w charger sounds just about right.