When you renew your car tags at the Davidson County Clerk’s Office or check out books at your local library branch, you are stepping inside one of the hundreds of buildings owned and operated by Metro Nashville Government. As good stewards of taxpayer dollars and the environment, Metro is committed to operating its facilities efficiently – conserving energy and water and reducing waste. In fact, legislation requires the city to improve the energy efficiency of its existing building stock, build to LEED standards, and pursue renewable power for its operations.
As the saying goes, “You cannot manage what you cannot measure.” This is certainly true of energy use. In order for Metro to operate buildings with energy efficiency at the fore, baseline energy use must be established and subsequent consumption tracked. This is why, in 2022, Metro Government conducted energy benchmarking across 335 facilities.
Benchmarking entails collecting basic information about each building (e.g., functional type, square footage, age) and logging one year’s worth of energy consumption (including electricity, natural gas, steam, and chilled water). Dividing energy use, measured in kBTUs, by square feet yields a facility’s Energy Use Intensity (EUI). An EUI score allows comparison to other similar type buildings. For example, does the fire station nearest you have higher or lower EUI than an average fire hall in your community, the region, or the country as a whole? EUI provides an answer.
The U.S. Energy Information Administration publishes the Commercial Buildings Energy Consumption Survey (CBECS), which allows Metro Government to compare our buildings’ EUI to a national average. While we celebrate buildings that are on par or more efficient when compared with CBECS, we also identify low-performing, energy inefficient buildings that become a priority for upgrades. LED lighting retrofits and HVAC upgrades can vastly improve the efficiency of these facilities.
In 2022, Metro Nashville Public Schools (MNPS), General Services, Farmers Market, Fairgrounds, Parks and Recreation, Metro Action Commission, Nashville Fire Department, Davidson County Sherriff’s Office, WeGo, Nashville Department of Transportation, and Nashville Public Library participated in energy benchmarking. Energy use across 335 facilities, representing 20.3 million square feet, totaled nearly 1.3 billion kBTUs. 1.3 billion kBTUs is equivalent to the annual energy consumption of nearly 17,000 households.
Metro Department Building Count – 2021 Benchmarking
- Fairgrounds (3 buildings)
- Farmers’ Market (1)
- Fire (16)
- General Services (91)
- Library (18)
- MAC (7)
- MNPS (140)
- NDOT (8)
- Parks (46)
- Sheriff’s Office (2)
- WeGo (3)
Total Energy Consumption (kBTU) for participating departments in the 2021 Metro Benchmarking Program was 1.3 billion kBTUs. Energy consumption comprised the total as follows:
- Fairgrounds (0.6%)
- Farmers’ Market (1.1%)
- Fire (0.9%)
- General Services (27.9%)
- Library (6.4%)
- Metro Action Commission (0.4%)
- Metro Nashville Public Schools (48.7%)
- Nashville Department of Transportation (0.4%)
- Parks (5.8%)
- Sheriff’s Office (4.3%)
- WeGo (3.4%)
Most of these city entities had never systematically tracked their energy consumption before. Experienced departments worked with novice ones to share expertise across city government. For example, General Services staff guided each agency as to how to collect data, enter it into Energy Star Portfolio Manager, and analyze the results. The process led to many productive conversations to identify why certain facilities are less efficient. Higher relative EUI could be due to a number of factors, including aging HVAC equipment, problems with the building envelope, 24/7 or afterhours usage, and more. Pinpointing problem areas helps staff prioritize projects and provides justification for budget requests or seeking grants.
This is just the beginning. As Metro Government continues to track energy use year upon year, trends will emerge. As upgrades are performed, resulting energy and cost-savings can be quantified. Launching Metro-wide benchmarking has started Metro agencies on a path toward energy savings and higher performing buildings. Ultimately, that means more efficient and comfortable facilities with a much lighter impact on the environment.