He was one of the inventors of the Hall-Héroult process for smelting aluminium, and developed the first successful commercial electric arc furnace.

[1] Paul Héroult is renowned for other major inventions, among them a self-supporting conduit still used to bring water down from mountain heights and across rivers to hydraulic power plants, avoiding the need to build expensive bridges.

He was highstrung, unruly, occasionally hard and insolent; he did not fit the image of wise, disciplined men of science.

He loved games, the company of women, travels by land and sea; he was a free spirit in an impetuous body.

Instead, his inventions appeared suddenly, out of the blue, a stroke of common sense, or of genius, sometimes during a lively game of billiards, his favorite pastime.