EPCG said in a statement it changed the deadline, initially set on November 4.
The utility said earlier this month it has earmarked 57.4 million euro ($86 million) for the purchase which will be divided into 16 lots.
"A bidder may submit a bid for one or more than one lot or the whole amount of electricity. […] Within each of the lots the bidder may submit a bid for delivery of electricity of a 10 MW minimum power," EPCG said.
Montenegro, with an installed generation capacity of 868 MW, suffers constant power shortages and increases electricity imports every year. Almost two-thirds of its electricity output is produced by two big hydro power plants, Perucica and Piva, and around one-third is contributed by its sole thermal power plant Pljevlja.
($=0.6686 euro)