Aligning around a standard metric for energy use

A long-held truth in management principles is if you want to improve something, you first need to measure and report on it. Innovation and improvement typically occur when a standard exists to compare and to publish performance of a product, such as the “miles per gallon” metric used for automobiles.

As Steve Selkowitz of Lawrence Berkeley National Laboratory’s Building Technology and Urban Systems Department (featured on cover) points out that while the way a building is used, operated and maintained is beyond the direct control of the construction team, a building’s energy performance can be influenced by decisions made during design and construction.

BENCHMARKING OPPORTUNITY

This presents an opportunity for us as an industry to help bridge the gap between predicted and measured building systems’ performance. It also begs the question: “How do we benchmark energy use as an industry?”

The industry needs to include a standard measurement for comparing buildings beyond Leadership in Energy & Environmental Design (LEED) so that tenants and owners/users can compare results to improve building performance.

An Urban Land Institute (ULI) panel that DPR participated on addressed the costs and payback of green strategies, such as LEED and net-zero energy initiatives. Several examples of recent DPR “dark green” projects, those certified as net-zero by the International Living Future Institute (ILFI), were presented. These include DPR’s Phoenix Regional Office, which was the world’s largest ILFI-certified net-zero energy building until October 2013. The “world’s largest ILFI-certified net-zero building” title was then awarded to another DPR project—the 51,000-sq.-ft. Packard Foundation Headquarters in Los Altos, CA.

These net-zero energy buildings generate 100 percent of their building energy through onsite renewable sources, such as photovoltaic (PV) panels, which both the DPR Phoenix office and Packard Foundation Headquarters employ.

WHAT TO MEASURE

Given that most urban buildings will not likely achieve net-zero energy consumption in the near future, we think the best metric for comparing these buildings is energy use intensity (EUI). EUI is calculated by dividing the total energy consumed by a building in one year by the total gross floor area of the building (kBtu/sf/yr). This metric is what the U.S. Environmental Protection Agency (EPA) uses to calculate Energy Star ratings.

We believe that the kBtu/sf/yr label should be required for all buildings. Of course, comparisons would need to be segmented to similar building types in similar geographies (e.g., office buildings in Chicago, houses in Atlanta, retail space in Seattle, etc.). This measurement could lead to more direct comparisons of buildings and results. It may also lead to legislation to require minimum energy performance standards for different building types.

If we truly want to improve overall building performance, our industry needs to align around standard metrics for energy use in the built environment to promote environmental responsibility and spur innovation.