The Poolbeg chimneys, one of the iconic landmarks in Dublin, could require some changes for their long-term survival.
Dublin City Council has warned that the two structures may need to be encased in fibreglass or concrete to ensure their stability.
It has also expressed concern over the ongoing costs to maintain the chimneys.
The council said the maintenance by the ESB runs to several million euro and this will only secure the chimneys in the medium term.
It also refers to the ESB's view that adding the chimneys to the Record of Protected Structures (RPS) will "not provide any additional security" to that provided under the maintenance programme.
The council added that it may impede any ongoing structural interventions or necessary external cladding in the future.
The twin structures, which were built in the 1970s, have not been in use for more than 10 years but the industrial landmark has become a striking feature of the Dublin skyline.
The council's warning about hefty costs and possible changes to the structures has sparked much discussion on their future.
Many living in the capital believe they should remain in place.
Several walkers on Sandymount Strand described the emotional attachment to the chimneys with the view of the structures being both "comforting" and "nostalgic".
Historians are mindful too that what was first viewed as an eyesore in the 1970s is now, for many, a treasured symbol of Dublin.
Historian Pat Liddy said that while they are not beautiful chimneys, they span several generations and people accept them as part of the landmarks of the city.
He said nothing beautiful can be kept, however, without maintenance.
"I think we have to accept that if we want to keep the chimneys, we're going to have to spend money on them.
"It's going to cost money to knock them down anyway. So if we love our chimneys we have to preserve them."
Mr Liddy gave the example of the Eiffel Tower in Paris which he said was built for a few months before it was meant to be knocked down, but the residents of the French capital said no as they wanted to preserve it.
Donal Fallon, a historian and producer of the podcast Three Castles Burning, compares the appeal of the chimneys to the Mona Lisa.
"They seem to follow you everywhere you go, they're looking at you all the time as you as you go across Dublin."
He also points out that Dublin is "not a particularly tall city" and the chimneys are one of the few things that really stand out.
Mr Fallon said it is interesting the discussion is happening now about their future as 2021 is the 50th anniversary of the first chimney.
"So that anniversary has inspired a lot of nostalgic looking back at them and thinking, particularly at this moment in time with lockdown.
"People are walking to see them all the time across the city. It's a time when people are really falling in love with them again"
In a statement, the ESB said it continues to work closely with Dublin City Council on the future of the chimneys.
