[az_gila]

Pressurized carbon dioxide is used to move the beer from the keg to the tap. Running out of CO2 is as bad as running out of beer.

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The good “real/craft beer/ale” spots in the UK still use an old-fashioned pump system. No CO2 tanks involved.

[IndispensableDestiny]

The good “real/craft beer/ale” spots in the UK still use an old-fashioned pump system. No CO2 tanks involved.

Cask beer and ale is pumped. But the story is about keg beer which isn't. Long ago, some beers were sold in kegs that could be gravity fed. I recall the galvanized ice tubs with a hole cut near the bottom for the gravity tap. A relief valve on top let in air.