The Kozienice plant - technically situated in the nearby village of Swierze Gorne - belongs to Poland's state-controlled energy group, Enea.
Built over the past five years for PLN 6.4 billion (EUR 1.5 billion), the new 1,075 MW block is compatible with the strict environmental standards of the European Union.
Moreover, as the biggest and most efficient coal-fired power-making facility in Poland (and one of the largest in the world), it will raise the capacity of the Kozienice plant by a third to some 4,000 MW, extending its life by at least four decades.
"The new block will boost the energy security of Poland and the Polish people," Morawiecki said at the unveiling ceremony, "which is one of the absolute priorities, economic as well as political, of our government."
The prime minister said that two years ago, the project had been in danger of falling behind schedule - which he had discussed with Energy Minister Krzysztof Tchorzewski at the time - yet the government had eventually managed to deliver it "almost on time".
In Morawiecki's view, this proves Poland has "great managerial abilities when it comes to implementing complex, multi-level economic projects."
The prime minister also noted the new block's efficiency, eco-friendliness and positive impact on the local community.
"It will be fired by coal supplied from the nearby Bogdanka mine, which is to say relatively cheaply," he explained, "and this is further proof that we are adopting a holistic approach, taking care of the whole state of affairs and the environment." (PAP)