Behind sand dunes on the Dutch North Sea coastline, clouds of smoke and steam billow from the mass of chimneys, pipes, and cranes that form the imposing Ijmuiden steelworks. Deep inside this vast industrial complex, which for almost a century has churned out metal for cars, construction and food cans, an experimental project is underway — to make steel cleaner and cheaper.

The plant’s owner, the Indian conglomerate Tata, calls its novel process a “game changer” capable of reducing both carbon dioxide emissions and energy consumption by one-fifth. “There is a very big duty for us, as the steel industry, because we are one of the biggest CO2 producers,” said Hans Fischer, the chief executive of Tata Steel Europe.

But despite more than a decade of gestation, this new steelmaking technology is unlikely to be rolled out on a commercial scale until at least the 2030s. “It’s not a financial reason, it is not an investment reason. In fact, it’s for technical reasons that it takes that long,” explained Mr Fischer. At a time of renewed international efforts to avert environmental disaster, the slow pace of progress illustrates the huge task to overhaul a monolithic sector that is the single largest industrial source of climate pollution.

Globally, steel is responsible for 7 percent to 9 percent of all direct emissions from fossil fuels, with each tonne produced resulting in an average 1.83 tonnes of CO2, according to the World Steel Association.