At Solnova 1, mirrors in the form of parabolic troughs concentrate sunlight in a pipe and heat up special oil, the so-called heat transfer medium, circulating in it. Another method consists of concentrating sunlight from numerous flat mirrors on a small surface at the top of a tower frequently over 100 meters in height. A range of different technologies will likely be used on the visionary Desertec project: the project plans to transfer electricity from solarthermal power stations in Northern Africa to Europe. Over such a distance, this is only possible with little leakage using high-voltage DC transmission systems (HVDC). HVDC lines will constitute the backbone of future interconnected networks as “electricity highways”.