The term carbon footprint has become synonymous with greenhouse gas (GHG) emissions and climate change. Carbon footprint commonly refers to the volume of greenhouse gases, the most prominent of which is carbon dioxide, which are emitted by an organization, event, process or product. Because of climate change concerns, coupled with rising energy costs and dependency on non-renewable and foreign sources of energy, the related term energy footprint is entering the vernacular of industry and regulatory organizations.
The U.S. Department of Energy (DOE) developed energy footprints to help target energy saving opportunities in the manufacturing industry. They map the flow of energy supply and demand in facilities and show where and how the energy was used and lost from inefficiencies. The DOE uses energy footprint maps such as the one in Figure 1 to track the flow of energy supply, demand and losses.