Renewable energies (wind, solar, geothermic) are of intermittent nature. The balance of the network sometimes demands transporting electricity over hundreds, even thousands of Km. For example, the offshore wind farms of the Netherlands are made viable by an underwater 580 Km DC 450 kV link that connects the Netherlands to Norway and its important hydroelectric resources. But things get complicated in the case of overland connections, due to people’s growing opposition to pylons carrying aerial cables. Superconducting cables can carry a very strong current, and therefore reduce the voltage for the same power, without any heat dissipation. This results in an extremely compact system that could be laid underground along a road or railway.
Already, during our conference in Jordan, H.Schmidt had presented the possible use of high-temperature superconductivity at liquid hydrogen temperature. Unfortunately, the cost of ceramics made of Bismuth (Bi-2223) and of Yttrium (Y-123), as well as the difficulty of fabricating wires out of them, restricts their use at the moment to highly urbanized zones where the rights of way of aerial cables would be prohibitive.
During a conference organized by Carlo Rubbia, Scientific Director of the IASS in Potsdam, on the 12th and 13th of May 2011, a new possibility arose that, if confirmed, would completely change the story and make underground pipes competitive with aerial cables in the near future. The material MgB2 is inexpensive and easily drawn into wires, and by chance it was discovered in Japan in 2000 to become a superconductor at the temperature of liquid hydrogen. During our next conference we will give prominence to this possibility, which is still little-known.