Page 38 - Zero Net Energy Case Study Buildings-Volume 1

CASE STUDY NO. 1
PACKARD FOUNDATION HEADQUARTERS BUILDING
Packard Foundation Headquarters Building
140,000 120,000 100,000
80,000 60,000 40,000 20,000
0 -20,000 -40,000
Jan Feb Mar
Apr May Jun
Jul Aug Sep
Oct Nov Dec
Cumulative Net Energy Performance - 2013
Net Energy Production
Net Positive
Net Zero
22
Zero Net Energy Case Study Buildings: Volume 1
Post Occupancy: Observations and Conclusions
Post-Occupancy: Controls and Monitoring
The strength of the monitoring and data collection activity is a model of its kind. The ease of access to the data reporting as part of the overall automated controls system provides virtually instantaneous feedback to the occupants and the managing building engineer. Aside from an initial minor failure at one of the inverters on the solar photovoltaic system, which was quickly corrected, all systems communications have worked as intended.
Post-Occupancy: HVAC
Soon after occupancy, the air source heat pumps failed, creating a cold building in the morn- ing and immediately raising questions among the building occupants about the relation of the failure to the ZNE design. The cause was determined to be the inability of the specific type of heat pump, residential in quality, to operate effectively in a commercial application such as this comparatively large building. The replacement heat pumps were specified to be a hardier type of equipment, more capable of operating near or at their lower temperature limit, and the operation has been without incident since.
Packard Foundation leadership reported that some discussion about this event was necessary to make the point that the heat pumps were not the innovative basis for their new approach to building design. The analogy discussed with staff was that the organization’s new “hybrid car” just had several tires unexpectedly go flat. However, this failure event had the unfortunate effect, according to the design engineers, of generating a “myth” that the building does not have the heating capacity that it needs.
The system of distributed air handling units serving the active chilled beams did not employ any heat recovery components on the relief air. With the experience of the first year of operation, the design engineers now regard heat recovery with direct outside air systems (DOAS) as an important feature to include in future designs. The design engineers also note that larger thermal storage for heating would have improved performance when in heating mode.
With regard to cooling, the Foundation ultimately approved a small rise in the chilled water tem- perature as it passes through the active chilled beams. This is more energy efficient and reduces the amount of time that dehumidification is required. The dehumidification feature is now used
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