Alfred Büchi

[1] During his early years outside Switzerland, Büchi became fascinated with the challenge of improving combustion engine efficiency relating to exhaust heat loss.

[4] While a later patent (1925) describing "pulse operation for low-pressure supercharging"[5] is considered his landmark, due to Büchi's invention the year 1905 is thus acknowledged as the birth of the turbocharging era.

Intending to mitigate effects of thin air in high altitude for airplane engines, this version did not maintain consistent boost pressure and thus was not well received.

The first use of turbocharging technology was for large marine engines, when the German Ministry of Transport commissioned the construction of the passenger liners Preussen and Hansestadt Danzig in 1923.

Both ships featured twin ten-cylinder diesel engines with output boosted from 1750 to 2500 horsepower by turbochargers designed by Büchi and built under his supervision by Brown Boveri (BBC) (now ABB).

[2][8] Eventually near the end of his tenure at the firm, in 1925 Büchi for the first time succeeded in combining his technology with a diesel engine, increasing efficiency by over 40%,[3] the same year filing Swiss patent number 122 664 under his own name ("Büchi-Duplex turbocharging system").