The Croatian utility group said in a statement on Friday that, after reviewing the submitted expressions of interest, it has shortlisted for the next phase of the process Italy's Edison, South Korea's KOSEP, Japan's Marubeni and Poland's Pol-Mot.
HEP said it will invite the shortlisted companies to submit binding bids.
The submission deadline for expressions of interest from potential strategic partners to design, engineer, finance, build, operate and maintain the 500 megawatt coal-fired Plomin-C power station expired on September 14.
State-owned HEP has said it expects to select a strategic partner by the end of the first quarter of 2013.
($=0.7776 euro)