Editing Aller (Germany) (section)

== Water power ==
[[File:Aller (Fluss) Wasserkraftwerk Oldau 2008 by-RaBoe 02.jpg|thumb|Oldau waterworks]]
In upgrading the Aller between Celle and the mouth of the Leine near [[Schwarmstedt]] between 1908 and 1918, [[hydropower station]]s were built at two of the four new [[barrage (dam)|barrage]]s: [[Hambühren|Oldau]] and Marklendorf. They enabled the [[electrification]] of the [[Südheide Nature Park|Südheide]]. The Oldau station, with three [[Francis turbine]]s, was taken over in 1929 by [[PreussenElektra]]. In 1972, the power stations were closed as they were unprofitable. Whilst the structure in Marklendorf was demolished, the power station in Oldau was declared a technological monument and escaped destruction. After being modernised in 1983, it rejoined the grid. It has largely been preserved in its original state. Here, the water power of the Aller, with the aid of Francis turbines with a [[nominal power]] of 650&nbsp;kW, is used to generate 3 million [[kilowatt-hour|kWh]] per year of electric current.<ref>[http://www.niedersaechsische-muehlenstrasse.de/index.php?id=106 Wasserkraftwerk Oldau]</ref>