The body had been drifting in the Limmat river and was washed up at the power plant at around 11am, according to a police report.
City of Zurich police say there are no signs that the man – aged in his mid-fifties – met a violent death or that anyone else was involved.
However, the exact circumstances surrounding the death are unclear.
The police are looking for anyone who may have seen anything potentially linked to the death between midday on December 23rd and the 25th.