In the XX. century, the Paks Nuclear Power Plant was the biggest industrial innovation of Hungary. After completing the capacity upgrade of all units the nominal power of the NPP reached 2,000 MW. With this, Paks NPP has a leading role in Hungarian energetics: it takes part of more than 40 % in national energy production. In 2009, the four units produced 15,427 GWh electric energy. The sell-out price of generated electricity was only 10.67 HUF/kWh in 2009, which is the cheapest value in Hungary.The nuclear power plants are the more environmental-friend solution for energy production, according to other types of power plants. It is not emitting carbon-dioxide, so it can spare as much oxigen in a year, as consumptioned by 2 million people. This measure is equal the oxigen production of all hungarian woods. Therefore, Paks NPP is essential for Hungary in national energetics, in environment protection and in economy as well.