The electrical generating sector came into being in the last two decades of the 19th century in the industrial countries, with the first small installations of public capacity in the 1890s in the USA, UK and Japan, mainly for street lighting. In those early years and in years before manufactured town gas was a more important energy source in the cities. Electric power grew slowly during the first half of the 20th century, supplied by a myriad of small local companies mostly operating in towns. The Second World War was to change this and with the explosion of industrial activity that it unleashed, electricity became a major national priority. Many countries nationalised their electricity industries or grouped them into large consolidated utilities. Until then electricity had been generated and distributed locally but now electricity transmission entered the picture. Transmission lines were constructed to transport bulk power at high voltages over long distances from large centralised generating facilities to industrial and population load centres where it was distributed at low voltage.
In 1938, the electrical industry was dominated by Europe with 59 GW in 1938 and North America with 46 GW. Only two other countries were electrically significant, the USSR with 8.9 GW and Japan with 10.4 GW. In 1950 this re-mained the case but all countries were building capacity and the spread of industrialisation which characterised the second half of the last century had begun.
The increase in generating capacity has continued without interruption for the last sixty years, dominated by two surges, when the rate of growth escalated. The first surge was throughout the 1970s, tailing off slightly in the following decade of the 80s, but escalating even faster in the last ten years.