Develop Simulation-Assisted Commissioning Procedures

Goal Statement:
To develop simulation-based functional test procedures for use in commissioning at the whole-building level.

Computer simulations have not been used to assist in commissioning of buildings except in isolated instances. One reason is that most computer simulation tools were developed for design purposes; as a result, their interfaces are not set up so that a user can easily compare actual performance of a building with simulated performance on a real-time or near-real-time basis. This task aims to: assess the potential of whole-building energy simulation programs to predict the actual performance of large commercial buildings; develop simulation-based functional test procedures and automated fault detection and diagnosis procedures; and assess, through field trials, the type and degree of faults that can be detected and diagnosed using on-line simulation.

Results:
Completed the assessment of EnergyPlus and ASHRAE Simplified Energy Analysis Procedure (SEAP) capability to provide accurate, on-line diagnostic simulation of large commercial buildings. Some conclusions from the draft report are:

• Whole-building simulation programs have the potential to act as a reference for real buildings.
   
• Sensors in addition to those usually installed in energy management and control systems will sometimes be needed to supplement simulation data.
   
• Standard communication protocols currently being adopted in the building controls industry have the potential to interface with on-line simulation programs.
   

Multilevel simulation interaction with a typical building control system

Field trials of simulation-assisted procedures were started during the fall of 2002. The sites are:

The Aksarben 2 (AK2) building of the First Data Resources Company (FDR), located in Omaha, Nebraska. The building was constructed in 2001 and has four floors with a total conditioned floor area of about 20,000 m². The building is conditioned by two air-handling units served by two chillers and 10 boilers.

The Sbisa Dining Hall, a 137,900 ft² (12,800 m²) facility built in 1912 on the Texas A&M University campus. This single-story building with 18-foot (5.5 m) ceilings and a partial basement houses a large kitchen; most of the main floor is broken up into large dining halls with multiple food serving areas. One small wing contains offices for student life organizations. The conditioned portion of the basement contains a food court with several fast food vendors and a convenience store that sells food and other items.

Downloads and Links:

• "Potential of On-line Simulation for Fault Detection and Diagnosis in Large Commercial Buildings with Built-up HVAC Systems", Energy Systems Laboratory, University of Nebraska and Energy Systems Laboratory, Texas A&M University. June 2002. (2.8 MB, 58 pp)
   
• "Development of Whole-Building Fault Detection Methods", M. Liu and L. Song, Energy Systems Laboratory, University of Nebraska; D.E. Claridge, Energy Systems Laboratory, Texas A&M University. June, 2002. (1.04MB, 22 pp)
   
• "Use of Whole Building Simulation in On-Line Performance Assessment: Modeling and Implementation Issues", P. Haves, et al. Published in the Proceedings at the Seventh International IBPSA Conference on Building Simulation 2001, August 13-15, 2001 in Rio de Janeiro. (1116 KB, 11 pp)
   
• "Field Testing of Component-Level Model-Based Fault Detection Methods for Mixing Boxes and [Variable Air Volume] VAV Fan Systems", P. Xu and P. Haves. Presented at the American Council for an Energy-Efficient Economy (ACEEE) 2002 Summer Study on Energy Efficiency in Buildings and published in the Proceedings. May 2002. (1.62 MB, 13 pp)

Contact: Philip Haves, Lawrence Berkeley National Laboratory (LBNL), (510) 486-6512