UConn Office of Environmental Policy

Promoting sustainability at UConn

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Hidden Energy Savings: Retrocommissioning and Relamping

The University of Connecticut is in the midst of an extensive retrocommissioning and relamping project as part of the energy efficiency priority of UConn’s Climate Action Plan.

Retrocommissioning (RCx) is the process by which the systems and equipment of existing buildings are tested and modified so that the building is running optimally and efficiently. UConn has broken up its retrocommissioning projects into three phases over four years starting in 2011. As of Summer 2013, the university had completed retrocommissioning projects for 19 buildings. These projects, along with other UConn energy efficiency measures, should save over 20,500,000 kWh of energy over the course of a year. The largest savings are coming from the Homer Babbidge Library, the Pharmacy Building, and the Student Union.

andy figure

Figure 1: Data from projected annual energy savings in LOAs for Buildings in Phase 1 and 2


Of course, energy isn’t free, so in addition to saving energy, retrocommissioning should save the university about 2 million dollars a year.  Phase 3 of the retrocommissioning projects is set to begin in Fall 2013 and continue through 2014. Some of the buildings that will be included in Phase 3 are the South Campus Dorms, the Music Building, the Dodd Center, Von der Mehden Recital Hall, and the School of Fine Arts.

Relamping is another ongoing energy efficiency project at the University of Connecticut. Relamping works to upgrade the lighting systems of a building by replacing inefficient bulbs with more efficient varieties. These upgrades will increase energy efficiency, decrease overall energy use, and reduce greenhouse gas emissions moving UConn forward with its sustainability goals. As of the end of the summer, 80 relamping projects had been completed at UConn. As a result of this effort the university is projected to save 4,065,870 Kwh of energy and $398,013.06 per year. It is incredible that a seemingly small change, like light bulbs, can amount to such large savings.

Both retrocommissioning and relamping are excellent examples of UConn’s proactive and effective push for sustainability. Although most people don’t see the changes from retrocommissioning and relamping, they are one of our most effective energy-saving tools! The average reduction in energy from a retrocommissioning project is 16 percent and the implementation of new lighting systems can reduce lighting energy demand (29% of a buildings total energy demand) by 59%. UConn recognizes the value of both relamping and retrocommissioning and has made them priorities in the Climate Action Plan.



Retro-commissioning at UConn

by Alexander Samalot, OEP Intern

The variable frequency drive

UConn is currently undergoing a significant conservation and construction effort that many students may not know about. Currently buildings are becoming drastically more efficient through adjustments in the way energy is handled. I recently sat in on Sebesta’s (an engineering and design service company hired by the school) meeting. They were explaining to the UConn Utility services the changes that have been made across campus followed by a tour of the newest completed building, the Agricultural Biotechnology Laboratory.

What Sebesta has done is a process called retro-commissioning. It involves specifying building occupancy schedules, allowing for certain utilities to be turned down or off when not needed. Previously buildings would run the CO2 and heating/cooling ventilation based on the hours that the building had expected use. This wastes a tremendous amount of energy for unused space. Even small changes in the run time and rate of heaters and chillers and ventilation can have exponential savings.

The pumps controlled by the variable frequency drive

Most of the explanation regarded the changes in the newest retro commissioned building, the agriculture biotech facility. Due to these changes there is supposed to be an annual savings of $112,000. The large number of laboratories in the building needs a significant amount of ventilation for the potentially dangerous chemicals. The laboratory I toured was a Biosafety level two (out of four). It is not a life threatening area; biosafety level two simply means certain biological agents may be used in the lab, which demonstrates the need for lab ventilation.

There are three places which were specifically retro-fitted; one is the lab itself, the fume hood and the biosafety cabinet.  There are new controls using top of the line technology such as infrared and camera controlled zone pressure sensors. This is a very technical way of describing a box which detects if someone is sitting in front of the hood, which automatically turns off the ventilation when not in use. Also there are new valves called VAV’s which open and close using a mechanical arm when not in use and operate at a highly reduced flow. The building itself offers Variable Frequency Drives which are newer computers controlling water and air pump motors that move all of the warm and cool air and water throughout the building. These controllers drastically decrease the energy costs of the building causing very large savings and reduced energy use.

The Retro commissioning project is a great example of how new technology can be successfully implemented to have a large effect on campus. The existing buildings have had their existing infrastructure optimized resulting in notable reductions in energy use and savings for the school. With the construction of so many new buildings on campus focused on sustainability , it’s important to remember that there are buildings on campus that are over sixty years old that have significant room for improvement.