Page 34 - Designing for Zero Carbon-Volume 2_Case Studies of All-Electric Multifamily Residential Buildings

CASE STUDY NO. 1
IVY SENIOR APARTMENTS
255,000 kWh/year Modeled EUI = 22.0
Design Analysis: Optimizing Zero-Carbon Design
Design Analysis: Embodied Carbon
An embodied carbon analysis was not undertaken because the type of structure and construc- tion materials to be used in the new building were standard wood-frame and cost effective, so that low embodied carbon content was expected for the eventual design solution.
Design Analysis: Energy Modeling and Operational Carbon
As part of the Title-24 energy code compliance, an energy analysis was done using the Californ- nia Building Energy Code Compliance Software - Residential (CBECC-Res). The result for the total annual (electrical) energy use for the entire building is 255,000 kWh, or an EUI equal to 22.0 (kBtu/sq.ft. per year).
The energy provided by the on-site solar thermal and solar PV systems was also modeled. The energy produced by the solar thermal system was predicted to be 14,462 kWh per year and, using PV-Watts8, the contribution of the solar PV system was estimated at 73,280 kWh. To- gether, the two renewable energy systems would be expected to reduce the annual energy use to 167,147 kWh, a reduction of 34%.
8 See: https://pvwatts.nrel.gov/index.php
Modeled Annual Energy Use
(CBECC-Res Software)
PHOTO: JEREMY BITTERMANN / JBSA
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