The Zwentendorf nuclear power plant on the Danube, near Tulln in Lower Austria, was planned in the 1970s as Austria's first commercial nuclear power plant. Construction began in 1972 and was essentially completed in 1976. The plant was designed as a boiling water reactor with an electrical output of 730 MW and was considered modern and safe by the standards of the time.
Despite its complete construction, the power plant was never put into operation. The decisive factor was the referendum on November 5, 1978, in which 50.47% of Austrians voted against its commissioning. The National Council subsequently passed a law prohibiting the use of nuclear energy for electricity generation in Austria. Thus, Zwentendorf remains the only completed but never operational nuclear power plant in the world.
In the following decades, the plant was not dismantled but continued to be used. Since the 2000s, it has served as a training and education center for power plant and safety personnel, as a real reactor without radioactive radiation offers a unique training environment. Guided tours, technical training sessions, film shoots, and events also take place there. A photovoltaic system was later installed on the site, making it a symbol of the energy policy shift and Austria's decision against nuclear power.