A dry winter following a hot summer in 1921-‘22 led to a lack of water, which seriously decreased hydroelectricity production in Italy. In the Po Valley, in the northern part of the country, this forced local governments to take action. The provinces of Piedmont, Lombardy, and Venice – Italy's industrial heartland – appointed special commissioners to ration the available electricity to industry. Besides this rationing, Switzerland supplied extra electricity. Technically this was possible, as transmission lines crossed the Italian-Swiss border and Italy already imported electricity from Switzerland. Electricity suppliers in France took part as well. French coal-fired plants in Nancy and Vincey supplied electricity to Zurich, Switzerland. The latter town normally received electricity from the Swiss plants in Brusio and Thusis. Northern Italy now consumed that electricity. According to the commissioner for Lombardy, Milanese engineer Angelo Omedeo, these electricity transmissions avoided “consequent shutting down of factories owing to lack of motive power”.

At this point in time an international solution – electricity exchanges between countries – seemed obvious to a solve a local problem – electricity shortage in northern Italy. Why this was possible, and how this situation was still rather unique needs historical explanation. By 1921 transmission lines traversed national boundaries for over two decades. The earliest cross-border interconnections, mostly 60-70 kV lines, could not play an important role beyond the local level, however. Often these connections transmitted electricity produced by power plants situated on border rivers.

But after the Great War, two major developments took place. A first major change was the use of higher voltages for transmission lines. This enabled the transfer of electricity over longer distances, without uneconomical losses in charge (see Table 2.1). Since then, higher voltage transmission lines interconnected the border regions between Germany, Switzerland, France, and to a lesser extent Italy. According to Lundgreen, the use of “high-voltage electrical technology opened the doors to a revolution in machine building, […] lighting and transportation, […] to the production, storage and distribution of current via central power stations”. Second and related, the average power plant capacity increased with the construction of so-called supercentrales or Überlandwerke. At the time the rapid increase in capacity resonated in consecutive claims of several new plants to be the largest in Europe. As the name Überlandwerk already implies, these plants served consumers far beyond the local.