The submarines can operate at high speed on diesel power or switch to the AIP system for silent slow cruising, staying submerged for up to three weeks with little exhaust heat.

The German Submarine Consortium built them at the shipyards of HDW and Thyssen Nordseewerke GmbH (TNSW) of Emden.

[citation needed] On 21 April 2008 the Italian Navy ordered the optional second batch of submarine, in the same configuration of the original ones.

[10] On 22 December 2015 Admiral Giuseppe De Giorgi, Commander in Chief of the Italian Navy, announced plans to build another two U212A submarines.

[14] This "CD" (Common Design) variant of the Type 212 will consist of six submarines, with the German Navy ordering two new boats alongside the four Norwegian vessels.

This is a long-standing requirement for German submarine designs, enabling them to pass a strategic point in the Baltic Sea (the "Kadettrinne") submerged.

[citation needed] Although hydrogen–oxygen propulsion had been considered for submarines as early as World War I, the concept was not very successful until recently due to fire and explosion concerns.

The gases are piped through the pressure hull to the fuel cells as needed to generate electricity, but at any given time there is only a very small amount of gas present in the crew space.

In April 2006, the German Navy's U-32 sailed from the Baltic Sea to Naval Station Rota in Spain in two weeks, going 1,500 nautical miles (2,800 km; 1,700 mi) without surfacing or snorkelling.

In 2013, while on the way to participate in naval exercises in U.S. waters, the German Navy's U-32 established a new record for non-nuclear submarines with 18 days in submerged transit without snorkelling.

[23] On 15 October 2017, the German Navy's U-35 suffered damage to its rudder fins while conducting dives off the Norwegian coast.