At a 2017 Phoenix rally, Trump championed “clean coal,” though he seemed unclear as to what it was.

We’ve ended the war on beautiful, clean coal, and it’s just been announced that a second brand new coal mine where they’re going to take out clean coal – meaning they’re taking out coal, they’re going to clean it – is opening in the state of Pennsylvania.

“Clean coal” has nothing to do with the mining and extraction process. It refers to various complex technologies used to mitigate the carbon emissions that arise from burning coal, the dirtiest of fossil fuels. Championing coal was a core component of Trump’s 2016 campaign.

Because of the cost associated with developing and implementing such technologies, the term “clean coal” has been derided by critics as a fabrication. The Sierra Club has long maintained that “clean coal” is an oxymoron, and that there is no way to “clean” coal to any substantive degree that would be superior to alternative forms of energy.

Despite being a climate change denier, in 2017, the CEO of the United States’ largest coal company agreed.

Murray Energy Corp. CEO Robert Murray explained, “Carbon capture and sequestration does not work. It’s a pseudonym for ‘no coal.’ It is neither practical nor economic, carbon capture and sequestration. It is just cover for the politicians, both Republicans and Democrats that say, ‘Look what I did for coal,’ knowing all the time that it doesn’t help coal at all.”

Live Science – Trump Touts ‘Clean Coal’: What Is It, Really?
Sierra Club – There’s nothing clean about coal and nothing funny about its impacts
E&E News – Pruitt will launch program to ‘critique’ climate science
Wikipedia – Coal pollution mitigation