A to Z of Innovations at Expos: Alternating current

From cordless elevators to machines that make water from thin air, visitors to Expo 2020 Dubai, can expect to discover a myriad of cutting-edge technologies that will shape the future, just as visitors to past Expos were offered a glimpse of what was to come.

Looking back at some of these, the A to Z of Innovations at Expos will offer a snapshot of some of the iconic products, inventions and technologies made famous at Expos and that went on to make their mark in the world.

Starting with A is a ubiquitous feature of modern life: Alternating current. By the late 19th century, electricity – while still a recent form of technology – was becoming increasingly widespread and saw its significance grow at each successive Expo. At Expo 1893 Chicago – the World’s Columbian Exhibition – Organisers, determined to showcase the positive side of modernity, made the decision to fully electrify the whole 190 ha Expo site.

The awarding of the contract to power the site was far from straightforward and was subject to one of the most intense corporate and technical rivalries of the period: the War of Currents (now the subject of a feature film). With General Electric proposing its direct current (DC) system based on Thomas Edison’s inventions, Westinghouse offered the newer, cheaper and more efficient Alternating Current (AC) system, developed by Nikola Tesla. While General Electric raised concerns over the safety of the AC system, Organisers opted for it, putting Tesla’s system on display for the whole world to see. The scale of the Expo site’s electricity use was unparalleled – it used up three times as much electricity as the whole city of Chicago. The success of the Expo – and Westinghouse’s victory – marked the arrival of Alternating current as the future of electrical power, shaping the technological landscape for decades to come.