Edison, the Italian subsidiary of French energy group EDF, said earlier this year it would sound out investors over the possibility of selling three natural gas storage sites it manages in Italy.
Italian gas distributor Ascopiave (ASCI.MI), Czech energy group EPH, Australian infrastructure group Macquarie and gas grid operator Snam (SRG.MI) have all filed non-binding offers for Edison's storage business, the sources said.
They added all the bids had a value of more than 600 million euros.
Both Snam and Ascopiave have recently said they were interested in the assets. Edison, EPH and Macquarie were not immediately available for comment on the issue.
The energy crisis triggered by Russia's invasion of Ukraine showed last year how large gas storage facilities allow a country to build an energy buffer to face potential consumption peaks during the winter.
Edison's gas storage business posted core earnings of around 50 million euros last year. The business has a regulated asset base of around 500 million euros, according to the sources, referring to unpublished figures.
