Narrative:
The building uses a structural steel frame with an exposed acoustic metal deck with concrete fill to provide thermal mass for night ventilation cooling. Walls were constructed with 2x8 and 2x10 wood studs (rather than conventional steel studs) to minimize thermal bridging and provide ample insulation. Glazing in thermally broken frames is Solarban 70xl and great effort was made to effectively shade the glazing.
A small cooling tower evaporates water at night to chill the water down to 55 degrees, without energy-intensive compressor based air-conditioning. This water is stored in the 15,000 gallon underground cistern, and cools the slab through radiant tubes the following day. The same radiant tubes also heat the building via a condensing boiler.
This building is designed to achieve an energy use intensity (EUI) of 6.74 kBtu/sf/yr including the energy generated by the PV array, and to use less than half as much energy as California’s strict energy code. A new 95.5 kW photovoltaic array was installed on three existing buildings that had the best slope, orientation and lack of obstructions.
Metrics:
Total EUI:
20kBtu/sf/yr
Net EUI:
7kBtu/sf/yr
Percent Reduction from National Average EUI for Building Type:
82%
Lighting Power Density:
0.17watts/sf
Energy Flows & Future Energy
source: http://www.aiatopten.org