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Energy Use Index

What is an EUI?

An Energy Use Index is a basic measure of a facility’s energy performance on a per square foot basis.  It is typically measured as kBTUs of energy used annually per square foot.  A BTU, British Thermal Unit, is a basic measure of heat value (energy content) of fuels.  All energy consumed by a particular building; i.e., electricity, natural gas, etc., is converted to a thousand BTU’s, added together, and divided by the total square footage.

Certain building types will always use more energy than others.  For example, a park building uses relatively little energy compared to a paramedic station.  Similarly, a small office building that supports 80 workers will use less energy than a jail facility that supports hundreds of people on a continual basis 24/7.