Page 38 - Zero Net Energy Case Study Buildings-Volume 2

CASE STUDY NO. 7
DPR CONSTRUCTION OFFICE BUILDING
Cumulative Net Energy Performance May 2014 - Apr 2015
Net Energy Production
Net Positive
Net Zero
26
Zero Net Energy Case Study Buildings: Volume 2
Post Occupancy: Observations and Conclusions
The low-energy design strategies that were incorporated into the design met the financial criteria established for the project. The performance data that started being collected at the occupancy date of May 2014 confirms the achievement of a minimum of ZNE performance for this renova- tion project in an urban setting, meeting strict financial constraints and an aggressive design and construction schedule.
Post Occupancy: Controls and Monitoring
The issue of accuracy of the meters being used for building energy use continues to be con- sistent with the case study projects. As noted in early case study discussions in Volume 1, care must be taken to specify the correct size for current transformers (CTs) to ensure correct read- ings. The conclusion, based on the experience with several case study buildings, is that the meters must be commissioned along with the rest of the building systems. This task is most often not included in the normal base scope of commissioning agents.
In the case of the DPR Construction Office Building, the master system integrator had to work closely with the technicians from the different control systems manufacturers to make sure the controls communications were working properly. Although manufacturers generally adopt one of the three major communication protocols and follow the associated standards, they sometimes “tweak” these protocols to suit their product’s functionality and product information sheets are not updated accordingly.
The one control system that couid not be integrated was the new skylight opening controls. The new skylights specified were manufactured in Europe and the communication protocols were incompatible with the master control system. These skylights had to be left as manual operation only.
Post Occupancy: HVAC and Commissioning
Early results of measurements of energy use in the first couple of months indicated that more energy was being used in the newly renovated building than the model indicated, to the point that the performance target of ZNE for the first year was not going to be reached. With this in-