Mixing hydrogen and pasta-making is a gambit in a multifaceted campaign by Marco Alverà, the chief executive of Snam, an operator of natural gas networks in Italy and across Europe. Snam, whose Italian operations are valued at 20 billion euros, or about $21.9 billion, chose an industrial area that is home to Orogiallo, a pasta company, for an early trial. Mr. Alverà has embraced hydrogen as a clean substitute for natural gas. Hydrogen has some major virtues. It is emissions-free and, he hopes, can be carried in Snam’s existing 25,000-mile web of transmission lines. When used as a fuel, hydrogen’s only byproduct is water. But the most common way to produce hydrogen requires fossil fuels, themselves heavy emitters, which would zero out the benefits of hydrogen use. There are clean ways to make hydrogen, with renewable energy — but then why not just use those clean energy sources as fuel on their own? The answer is storage. Excess renewable energy from wind and sun is often wasted. Using it to create hydrogen, which can be saved for later, is like having a large, relatively cheap battery, advocates say. Despite concerns about safety and cost, hydrogen could win a substantial portion of the energy market of the future and become a winning ticket for Snam. The company estimates that in three decades, about a quarter of Italy’s energy could come from hydrogen.