Non-Alcoholic Beer

One of the topics I love banging on about is how rarely anything genuinely new appears in the world of beer. So you can imagine how delighted I was to come across an old reference to alcohol-free beer.

The process being used was to brew an alcoholic beer and then remove most of the alcohol through evaporation.

Non-Alcoholic Beer.
The process of reducing the percentage of alcohol in beer, to the limit of one per cent, of proof spirit, followed by cold storage, filtration and carbonation of beer, is very interesting, the ordinary vacuum pan being of very little service. Alcohol no doubt is sufficiently volatile, but to ensure expulsion the fluid undergoing ebullition in the vacuum pan must be constantly circulated and sprayed at a temperature of 125 deg. F., for under normal circumstances “bready” flavour comes into existence, the period of treatment being altogether excessive. We have found it absolutely necessary to complete evaporation in one hour, and this is alone possible so long as the contents of vacuum pan exist in sheet form, a neat engineering achievement. With this proviso, the process can be carried to a very successful issue, the carbonated beverage being brilliant, sparkling, and non-alcoholic. The opening for genuine, non-alcoholic beer of the kind does not exist in England, but in Mass., U.S.A., the price secured for the article is a gratifying recompense for the trouble taken.
The Brewers' Journal vol. 38 1902, July 15th 1902, page 434.

Though note that this technique was being used in the USA, not in the UK. From the last sentence it sounds like back then, just as today, non-alcoholic beer was being sold for a similar price to the full-strength version.