Craig R. Dubler, Ph.D., Penn State University
Tabitha Sprau Coulter, Penn State University
With buildings accounting for approximately 39 percent of total energy consumption, it is important that they be maintained to continuously operate efficiently. Pennsylvania State University has more than 1,780 buildings. During the 2011–2012 year, these buildings emitted approximately 550,000 metric tons of carbon dioxide equivalent, which is a 27.5 percent reduction from what the university anticipated had it not implemented its reduction strategy plan. Penn State has more than 930 buildings on the University Park campus alone, which use approximately 400 million kilowatt hours of electricity annually. While Penn State has invested $40 million to re-commission and retrofit existing buildings, the university faces a challenge in determining how to invest funds to provide the greatest impact on energy savings.
Since 2009, the Office of Physical Plant (OPP) at Penn State has implemented BIM criteria on all major facility renovations and new projects greater than $5 million. The BIM criterion was developed by determining facility geometry and required to perform typical operations tasks. During early implementation, OPP focused on documenting attributes needed for the maintenance of major building equipment. The attribute information was added to the building models during the design and construction phase and then turned over to Penn State for its use for maintaining the facility. BIM has allowed data analysts to focus their attention on developing useful preventative maintenance plans rather than constantly entering facility data.
Over the past year, OPP has teamed up with the Department of Architectural Engineering to determine if a similar BIM method can add value to the energy auditing group's decision-making processes. Specifically, the team produced a research study using the following steps: 1) identify challenges with the current energy auditing process, 2) document the current auditing process and suggest where BIM can increase value, 3) determine the information required to be captured during design and construction using BIM, and 4) integrate the energy auditing information into future projects using standard modeling. The majority of the research was performed with the Energy and Engineering group at OPP using mixed methods consisting of face-to-face interviews, field observations, and structured focus group discussions.
Previous to this research effort, Penn State did not have a standardized process outlining the appropriate data necessary to perform effective energy audits. Through interviews, the team developed a process map that outlined the audit steps as well as the information requirements to make decisions. Figure 1 shows the formalized process OPP's Energy and Engineering group follows for selecting facilities for energy-based retrofit upgrades. The outlined portion of the map marked with an "A" shows the initial steps taken to identify which buildings will be targeted for the energy projects—an area the Energy and Engineering group has indicated difficulties with due to the lack of structure. The second outlined portion, marked with a "B," indicates when OPP receives the formal project proposals. It was determined that BIM could provide value to each of these portions of the auditing process.
After determining the information required for energy auditing, the research team focused on testing the capabilities of BIM and standardizing model families for future project collection. Figure 2 shows how energy meter parameters would be extracted from a record model and an example of the standard attributes that will be used on future projects. Through standardizing OPP's energy auditing process, identifying the key information required to produce accurate energy audits, and establishing opportunities where the energy data can be tracked using BIM, Penn State is better positioned to achieve energy reduction goals. While it will take time to integrate all energy information, Penn State has established a working model that has yielded success with previous efforts.
Figure 1: Penn State's Process for Selecting Energy Projects>
Figure 2: Energy Meter Data Required by OPP