The concept of a circular economy was not originated by a single person. Although the concept underlying it was first discussed in the middle of the twentieth century, the phrase itself is mostly a 21st-century invention.

Clean coal refers to various technologies designed to mitigate the environmental impact of coal usage, primarily through methods such as wet scrubbers for sulfur dioxide removal, coal washing to eliminate impurities, and digitalization to enhance efficiency. The main practice of clean coal employs carbon capture and storage (CCS) technology, which captures carbon emissions from coal burning and then safely buries them underground. Technologically, CCS functions properly, yet maintaining economic feasibility requires a big monetary investment to construct supporting infrastructure. The promotion of clean coal to enhance coal sustainability led to its temporary political status as a futuristic solution because coal naturally produces environmental pollution.