Energy Code Controls Verification and Field Research – Pacific Northwest National Laboratory (PNNL) – Oregon, Washington, Idaho, Utah, Wyoming, and Colorado.
Efficiency Planning, Research and Development
Solarc was prime consultant for an energy code-related field research and statistical analysis effort to document the degree of successful implementation of mechanical and electrical control requirements contained in current energy codes. Fourteen control requirements were investigated – ten mechanical requirements and four lighting control requirements. Design document review and field inspections were conducted on (24) buildings in six states and three climate zones, totaling over 1,800,000 sq.ft. Buildings were required to have been completed and occupied with the past two years. Solarc defined, led, and executed all of the tasks involved and listed below.
• Building participant identification and recruiting
• Definition of key performance and measurement metrics for each control requirement
• Development of database for documentation and statistical analysis of findings
• Scheduling of field visits and ongoing communication to obtain documents for review
•Review of design documents
• Field visits and data collection
• Completion of database and statistical analysis
• Final report
The project was under a tight timeline and budget from its inception. Solarc completed the work on time and on budget while working in a closely coordinated manner with the PNNL project manager and stakeholders. This project is a good example of Solarc's capabilities to organize our staff located in multiple offices, marshal focused efforts, and deliver on projects that require both staff experience and bandwidth.
Summary of Buildings Involved by Location
• Oregon: Four buildings (136,611 sq.ft.): one office, one fitness center, one multi-purpose building, and one middle school.
• Washington: Six buildings (399,300 sq.ft.) two offices, two residence halls, two medical clinics.
• Idaho: Three buildings (154,750 sq.ft.): one retail store, two elementary schools.
• Utah: Six buildings (721,470 sq.ft.): one supermarket, one hospital, one medical clinic, one office, one university science building, one high school.
• Wyoming: Four buildings (332,400 sq.ft.): one athletic complex, two high schools, one university laboratory. Colorado: One building (46,000 sq.ft.): medical clinic.
The following high level findings were outcomes of the research. The final report, as published by PNNL, can be viewed and/or downloaded at the following link: WWW.ENERGYCODES.GOV
• Controls always have more capability to achieve more complete compliance. While design documents are reasonably compliant, actual configuration tends to regularly fall short of design capability. This is true with or without commissioning. Modifications to the commissioning process may be warranted. These could include an end-of-warranty period re-commissioning effort that overlays code control requirements among other metrics to ensure that system configuration is optimized.
• New code requirements warrant follow-up research. This effort was initially targeted to address zone isolation damper control requirements among fourteen total control measures. As it turns out, this requirement is essentially a “new” code requirement and was not relevant to any of the subject buildings in this field research effort. Recent versions of relevant energy codes include even more new control requirements, i.e. plug load controls. It may make sense to plan for a follow-up research effort once the new codes are uniformly established throughout the United States. Such an effort could capture similar data as presented herein relative to these new code control requirements.
• A small number of measures exhibit higher than average non-compliance. About 40% of the overall data-set exhibited non-compliance, these data points were concentrated in a small number of measures. These measures are listed below as ranked by actual configuration. Market outreach to the design, enforcement, construction, and operations communities should target these measures in some respect.
- Zone isolation damper controls
- Optimal start controls
- Unoccupied period setback
- Automatic outside air damper controls
- Daylighting controls
- Economizer controls
- Static pressure reset
- Simultaneous heating and cooling limit controls
• Several causes of non-compliance occur regularly. Regularly occurring underlying causes of non-compliance are particularly noted with daylighting controls, and HVAC controls related to unoccupied period operation.
- Several of the most non-compliant HVAC control requirements relate to unoccupied period HVAC operation. Most of the seriously non-compliant observations occurred with HVAC systems that were allowed to operate continuously when serving spaces that are completely unoccupied for extended periods. This appears to be a regular operational occurrence among commercial buildings, and was noted to occur in over 20% of the subject building population sample.
- For daylighting controls, lack of compliance is typically a result of control hardware (manual or automatic) that is simply not installed in required areas when automatic control is installed, controls are often set-up in such a way as to limit the overall energy savings effectiveness of the control operation.
• Relationship between design and operation vary by measure. For some measures, compliant design translates to compliant operation. For others, the opposite can hold true. It appears that the following measures have a reasonable correlation between compliance in design and subsequent compliance in actual configuration.
- Economizer controls
- Occupancy sensor controls
- Exterior lighting control
- Occupied temperature setpoint deadband