Clean coal technology

Mike Pence refuses to answer whether climate change is a threat to the U.S.

Vice President Mike Pence refused to say on CNN's "State of the Union" on Sunday whether climate change was a legitimate threat to the United States.

Expert Voices

Coal burned to make steel and cement is still a major emissions source

A concrete factory
A concrete factory. Photo: Carter Dayne/Getty Images

Although coal continues to be phased out of electricity generation, it remains integral to producing materials for infrastructure projects like buildings, bridges and roads.

The big picture: Coal is the most emissions-intensive fossil fuel, and steel and cement production account for more than 20% of the world's use. While options exist to reduce or eliminate coal from those processes, many of the necessary technologies require policies, incentives and new markets to bring down the costs of commercial deployment.