Alphabet's Google is in talks with Envicool and other Chinese firms about buying liquid cooling equipment for data centres, according to people with knowledge of a visit to China by one of the U.S. firm's procurement teams. Liquid cooling systems - which circulate water or other liquid over or around equipment - have become critical in AI data centers as the high-density computing generates more heat than a traditional air cooling system can handle. The visit by the team from Google's Taiwan operations this month reflects tight supply of parts for such systems, the sources said.