The development of renewable energy alongside urbanisation and population growth has made the transmission of electricity a pressing issue for policymakers. Urban centres are often located hundreds or thousands of kilometres from the source of energy, and unlike fossil fuels, renewables cannot be transported. In response to this challenge, “supergrids” are being developed using specially built cables using direct current as very high voltages (HVDC), allowing large volumes of electricity to be efficiently transported over long distances.

The development of supergrids in the 21st century is the continuation of efforts since the dawn of the electric age to increase capacity and scale up access to electricity. As early as Expo 1904 in St. Louis, Chester H. Thordarson showcased a half-million volt transformer, winning a gold medal for the invention which he built in only 28 days. But it was not until Expo 1915 in San Francisco that Thordarson set the bar for electrical transmission when the public were introduced to the million-volt transformer, part of the High Tension Research Pavilion within the Machinery Palace.