Chattanooga, TN: Energy performance

Energy Performance
Cumulative (vs. Baseline)40%
Annual (2020)17%
PORTFOLIO ENERGY PERFORMANCE

Better Buildings Challenge Partners strive to decrease portfolio-wide source energy use intensity (EUI) and to increase the percent improvement compared to a set baseline. The City of Chattanooga's portfolio consists of more than 120 buildings covering over 1.7 million square feet. Chattanooga, TN has improved energy performance by 40% from a 2013 baseline. Energy consumption during 2020 was notably lower than a typical year due to COVID-19 disruptions, which resulted in temporary building closures and reduced occupancy for much of the year. However, due to ongoing occupancy by critical core staff throughout the majority of the year, most municipally owned facilities included in the Challenge continued to operate on normal schedules and temperature set points and setbacks established with building automation systems. Additionally, ongoing improvements and upgrades, such as boiler replacements and completion of a major, 60+ facility LED lighting retrofit project, contributed to the reduction in energy consumption and improvement to EUI. The City's Showcase Project, the downtown Public Library, has completed the replacement of over 800 fluorescent bulbs with just over 100 LED lights, and is in the process of replacing a 40-year HVAC system. Construction of an electric microgrid serving the City's public safety campus will begin in spring of 2021 with a completion date in fall 2021. The campus houses the police and fire departments, as well as radio communications services used by emergency responders. The microgrid will increase the campus' energy security and operational resilience in the face of increasing risk of man-made and natural disasters while further reducing EUI and increasing the amount of power supply to the City from non-carbon based sources.

ENERGY PERFORMANCE BY PROPERTY

Looking at the percent improvement in energy performance across all buildings can provide insight into how an organization is saving energy.  The City of Chattanooga has achieved energy performance improvement of greater than 15% at more than 47 of its buildings with several of the city's properties experiencing even greater energy performance improvements. Although at this early stage there are 16 buildings that have experienced an increase in Source EUI, armed with the key performance metrics provided through utility monitoring in Portfolio Manager, the city is able to shift its focus on strategic improvements to the lowest performing properties that will result in the greatest energy performance payback for the capital invested.

IDENTIFYING OPPORTUNITIES FOR IMPROVEMENT

Property-level energy performance metrics, including EUI and percent improvement to date, are critical to track progress over time and identify opportunities for additional energy savings. Chattanooga's building portfolio consists of a wide range of property-types which results in a portfolio with a wide range of baseline EUI values. While the majority of the city of Chattanooga buildings have shown energy improvement since the baseline of 2013, the properties located near or below the 0% axis may indicate properties that present good opportunities for further improvement in energy performance and savings.