Electric highway to South America

01.12.2025

Source: E & M powernews

8,000 kilometers of cable, electricity trading with a time difference of three to four hours: The Climate Neutrality Foundation envisions an HVDC connection to South America.

Twice-a-year summer in PV electricity trading: the Climate Neutrality Foundation is proposing to connect the northern and southern hemispheres via a transatlantic extra-high voltage direct current (HVDC) transmission line. The idea is for a cable that would connect Germany, Belgium and Portugal with Brazil, Uruguay and Argentina. The electricity highway would be around 8,000 kilometers long, 5,000 of which would run under water.

The time difference of three to four hours and opposing seasonal generation patterns are intended to balance out generation surpluses and deficits between the northern and southern hemispheres. Electricity trading between the individual countries at the ends of the cable would also be supported, they say. In addition, the Iberian Peninsula would be better connected to the Central European grid.

The Wegener Center at the University of Graz has analyzed the idea of an HVDC cable between the EU and South America in terms of costs, benefits and supply effects. The scientists came to the conclusion that a link between the two continents could significantly reduce the supply gaps for photovoltaics and provide controllable power at competitive costs.

The costs for flexibly available power provided by a combination of photovoltaics and electricity storage are examined. This is reportedly based on optimization models for the entire EU load curve and Germany's residual load.

68 to 77 euros per MWh

At today's prices, electricity transmission from Brazil to Portugal would cost EUR 27 to 36/MWh, they say. In the long term, the scientists believe it is likely to cost between 8 and 17 euros/MWh.
For Germany, the calculations show that covering the residual load would lead to total costs for controllable generation of EUR 68 to 77/MWh. This is below the expected costs of gas-fired power plants based on climate-neutral hydrogen, which are likely to reach at least 400 euros/MWh.

"Our proposal is not an alternative to urgently needed backup capacities for 2030," write Rainer Baake, Director of the Climate Neutrality Foundation, and Professor Wolf Grossmann from the Wegener Center at the University of Graz. However, one or more transatlantic cables could reduce or even replace the additional backup capacity required in the 2030s and 2040s. The experts estimate ten to twelve years for planning, approval and construction.

The study by the University of Graz is available free of charge on the Internet.

Author: Manfred Fischer