https://www.cnet.com/news/ces-2019-this-kettle-heats-water-precisely-as-you-pour-it/ > Typically used in fancy espresso machines, PID controllers have also made their way into other kitchen appliances. Breville's Precision Brewer is one example. This $300 drip coffee maker uses a PID controller linked to an electric water heating system. > The Duo goes one step further. Instead of plugging into an AC outlet, the pitcher draws electrical power from a rechargeable battery. That makes it portable, not chained to a socket. Heatworks hasn't set a price for the Duo though, nor has it pegged a date for its availability.