Background
Eyde was born in Arendal as a son of ship-owner Samuel Eyde (1819–1902) and his wife Elina Christine Amalie Stephansen (1829–1906).
Eyde was born in Arendal as a son of ship-owner Samuel Eyde (1819–1902) and his wife Elina Christine Amalie Stephansen (1829–1906).
Eyde studied engineering in Berlin where he graduated in 1891.
He started his career in Hamburg, working with the railways where he planned new lines, bridges and stations. In 1897 he started his own business, Gleim & Eyde with his previous boss from Hamburg. He soon established offices in Kristiania and Stockholm, and by the turn of the century his firm was one of the largest in Scandinavia, with some 30 engineers.
Eyde and Kristian Birkeland met at a dinner party in 1903.
Birkeland was working on developing an electric arc, while Eyde had recently bought the rights to several waterfalls in Telemark. They agreed to cooperate to develop an electric flame.
This allowed Eyde to establish Det Norske Aktieselskap for Eletrokemisk Industri (today Elkem) along with the Wallenberg family who he had met in Sweden. The factory at Notodden opening on 2 May 1905.
The same year he founded Norsk Hydro-Elektrisk Kvælstofaktieselskab (now Norsk Hydro).
Eyde remained director-general of both companies. He was director-general of Norsk Hydro until 1917, when he resigned. He was offered a position on the board, where he remained until 1925, and a compensation of NOK 250,000 for ten years, and NOK 100,000 for the rest of his life.
In 1920, Eyde was appointed as Norwegian Minister to the United States.
Sam was a member of the Norwegian parliament in the period 1918-1920.