PIOMBINO, Italy — When Italy, in a major strategic shift, decided to break its dependence on cheap Russian gas in response to Vladimir V. Putin’s invasion of Ukraine, the government needed alternatives.
It scrambled to sign contracts with suppliers in countries like Algeria and Azerbaijan, and sped up its investment in wind and solar energy. But it also decided to purchase two large vessels able to turn shipments of liquefied natural gas from the United States, Qatar and sub-Saharan nations into gas that could run through onshore pipelines. A single one of them, destined for Piombino, a seaside port of 32,000 people on the Tuscan coast with a long history of industrial development, would help replace more than 15 percent of the gas once imported from Russia.
“Piombino’s unit is essential — it is a matter of national security,” former Prime Minister Mario Draghi said last month. “It is essential for our gas supplies.”
But in a complicated wrinkle for the new prime minister, Giorgia Meloni, whose top stated priorities are reducing energy costs and maintaining support for Ukraine, the mayor of Piombino, who is from Ms. Meloni’s own Brothers of Italy party, has led vibrant protests against the project.
Elected on a populist wave that supplanted more than 70 years of left-wing leadership, the mayor, Francesco Ferrari, has argued that the so-called regasification vessel would damage the environment and local fish farming, as well as driving away new business and tourism.
As a result, the debate over Piombino may pose the first big test of whether Ms. Meloni, who remained vague about the issue throughout the electoral campaign, can reconcile her pugnacious, opposition-centric political style with her responsibilities in government on an urgent project with relevance for Italy’s national security and European geopolitics.
“Our priority today is to curb energy bills and accelerate the diversification of our supply sources in any way,” Ms. Meloni acknowledged in her first speech to Parliament since being sworn in on Oct. 22, mentioning new gas drilling off the Italian coast and the construction of more renewable energy plants in southern Italy. But she did not mention Piombino.
Unlike its twin unit on Italy’s Adriatic coast, the vessel intended for Piombino, which would be about 1,000 feet long, cannot stay offshore for a series of technical reasons, the authorities say, but must dock inside the town’s tiny port.
“This is not a political clash between parties,” Mr. Ferrari said. “Regasification units are necessary in this context in Italy, but we believe that its collocation in a different place and in a different way would represent a much lighter burden for other communities than it is for us here.”
Mr. Ferrari took to the streets with hundreds of schoolchildren, steel workers, students and older residents on a recent morning in the city center, amid beating drums and banners reading, “No to the regasification unit,” and, “Enough with poisons in Piombino.”
“They are placing a bomb inside our homes,” said Viviana Barontini, 61, who has joined the marches since May. “What will we do if an accident happens? We have only one way out of town.”
The regional president of Tuscany has approved the project, but Mr. Ferrari, the mayor, has vowed to appeal and slow things up, and he has an unusual local political consensus behind him.
“Nobody in Piombino lives far enough from the unit,” echoed Camilla Bedini, 36, who walked the march with her 4-year-old son on her shoulders. “The port is inside our small town.”
Piombino, a picturesque medieval city center perched on a cliff that was once a major center for the steel industry, has often found itself on the front lines of the country’s resource crises.
For a century, the town lived off its steel mill. From a 2,200-acre site near the port, the factory produced steel to build railways across the country and employed over 7,900 people.
In the past decade, the city has suffered an enormous economic setback and the number of workers is down to 1,640. Blast furnaces ceased operating in 2014, and the Indian steel giant Jindal, which bought the plant, appears unhappy with it.
One of Italy’s first ironworks is now a wasteland of rusted warehouses and conveyor belts, dilapidated buildings and abandoned offices. A series of governments have pledged to reclaim the highly polluted site, including nearby “Monte Puzzo,” the stink mountain, where prosecutors believe waste was dumped illicitly.
Popular discontent with the neglect of Piombino, which became a symbol of resistance to the Fascists during World War II and was long a stronghold of the left, spurred voters to elect their hard-right mayor. But it also spawned a broader distrust of the authorities in general, which has fueled skepticism about the natural gas vessel.
“We have no more trust in the institutions, in laws and in politics,” said Roberta Degani, one of the main activists in the protest, shouting from a microphone during the rally.
Yet Mr. Ferrari gave assurances that the town’s protest would not get out of control — residents merely wanted to have a different future, he said.
“We have shipyards interested in our port, and fish farming could grow,” he said. “All of this will stall if the vessel comes here.” It might also affect tourism, with the giant vessel a potential eyesore in the dock.
Recent investment in the port has been substantial. The long and deep dock where the vessel would be anchored was just completed, using over 60 million euros of European funds. The idea was to build a facility to scrap large boats.
All those potential businesses are clearly on hold now.
The port also houses several fish farming companies that produce 60 percent of Italy’s fish, and the entrance to the pipe that provides saline water to the land-based farming basins is right next to where the floating unit would go.
“I understand the emergency very well, believe me,” said Claudio Pedroni, the owner of Agroittica Toscana fish farming. He said that his bills for gas, electricity and oxygen had gone from €80,000 to €350,000 a month.
“But we are still concerned about the regasification unit — it’s going to be right there,” he said, looking out of his office window in the eastern section of the port, less than half a mile from the vessel’s proposed location.
Mr. Pedroni acknowledged that, under pressure from fish farmers, Italy’s energy infrastructure company, SNAM, had agreed to pay for independent, real-time monitoring of the sea conditions around the vessel, to ensure that any effect of the industrial process on the sea would be recorded, and to provide warning of any potential threats.
Yet time is of the essence here. Having the facility in Piombino would allow gas deliveries to jump a bottleneck in central Italy, where work on the infrastructure has suffered yearslong delays because of protests from other communities, and help the country store gas for next winter.
“It is a classic Italian problem,” said Davide Tabarelli, the president of the Italian energy research institute Nomisma. “In the Netherlands, they have two vessels that are already regasifying, while we are still debating whether to have it or not.”