Linde (ticker: LIN) is the world’s largest industrial-gas company, part of an oligopoly of gas producers that operate around the world. For large customers buying gases such as oxygen or nitrogen, Linde builds gas plants on-site and locks in contracts for 10 to 20 years with built-in price escalators. It’s a business model that has produced steady earnings growth.The Niagara Falls plant, slated to open in 2025, is a new part of its growth story. It will use carbon-free hydroelectric power to make hydrogen, a clean-burning gas useful in industries like refining, steel-making, and fertilizer production. Hydrogen now represents less than 10% of Linde’s sales, but analysts see it growing in importance as the company invests in projects worth tens of billions of dollars.