Which material has the highest embodied energy per unit?

The material with the highest embodied energy per unit is plastic. Embodied energy refers to the total energy required to produce a material, encompassing the extraction, processing, transportation, and any manufacturing processes involved.

Plastics are derived from petroleum, and their production involves significant energy inputs at various stages. The extraction and refining of crude oil into monomers, followed by polymerization and processing into usable plastic products, require an extensive amount of energy. This can sometimes result in plastic having a higher embodied energy compared to materials like steel, cement, and copper, which, while also energy-intensive, have different processes of production and energy utilization.

In contrast, while steel and copper do have high embodied energies, they typically are lower than that of plastic. Cement does have a substantial embodied energy as well, especially due to the calcination process involved in its production; however, it generally does not surpass the energy demands seen in plastic manufacturing. Thus, plastic stands out as having the highest embodied energy per unit, making it an important consideration in discussions of material sustainability and environmental impact.