Benchmarking energy performance in commercial buildings

The main purpose of energy benchmarking in commercial buildings is to put actual energy consumption into perspective so that building owners and occupiers can take steps to reduce it. Many rating tools, such as the display energy certificate in the UK, are primarily based on floor area. This means that nearly empty buildings can receive a good rating while intensively utilised buildings are penalised, even though their energy use per person may be much lower. To provide more meaningful benchmarking requires consideration of the intensity of use. This paper proposes a simple approach to include occupancy density and hours of use in the benchmarking methodology for commercial buildings. The paper also discusses how landlord and tenant energy can be benchmarked separately to reflect who is responsible for the energy consumption. Finally, the paper suggests modifying the standard A to G rating scale used in the UK to better reflect the diversity of energy performance in commercial buildings.