The biggest fossil fuel players are making the message clear: The transition to a green future will require much more natural gas.

From Shell PLC to Chevron Corp., the world’s top producers plan to accelerate investments in the fuel. China keeps signing deals to buy liquefied natural gas past 2050, with European importers not far behind. The U.S. is forging ahead with new projects that will make it the world’s top LNG exporter for the foreseeable future.

This momentum marks a turning point for gas. The "cleanest” fossil fuel was seen as a short-term bridge to greener energy sources, and environmentalists have sought to phase it out amid worries that gas is far dirtier than advertised. Now, the idea that gas demand will peak anytime soon is disappearing.