Page 121 - Designing for Zero Carbon-Volume 2_Case Studies of All-Electric Multifamily Residential Buildings

CASA ADELANTE AT 2060 FOLSOM CASE STUDY NO. 5
Domestic Hot Water Systems
There is a large central heat pump water heating system for the entire building.26 Initially, a solar thermal system was required27, but the project team secured an approval of an Alternate Materi- als and Methods Request (AMMR) and the solar thermal system was eliminated from the central heat pump water heating system. Experience with a similar project showed that solar thermal systems paired with heat pumps for water heating caused the efficiency of the heat pumps to drop significantly since the incoming water from the solar thermal system was too warm.
Appliances
Each kitchen is equipped with an electric resistance range with ceramic tops. Induction ranges were not specified because the unit price was significantly higher and the client understood that the tenants would be unfamiliar with the characteristics and requirements of induction cooking.
Lighting, Plug Loads and Control Systems
Energy-efficient LED light sources are employed with automatic dimming in response to daylight levels in the room. Control of lights by occupancy sensors provide additional energy-efficient operation of the lighting systems.
On-Site Energy Storage: Batteries
Electric energy is provided by the city-owned public utility, Hetch Hetchy Power. There is no rate structure applicable to this project where there would be an advantage to store energy generated by the solar PV system for use at a later time.
However, one of the client organizations, the CCDC, requires an emergency electric power backup system in all of its projects since most of its projects are senior housing. Since at the time of construction, the City of San Francisco prohibited battery backup for emergency elevator egress, the CCDC requirement resulted in the installation of a diesel generator. (The City of San Francisco and the CCDC have since modified this requirement—batteries are now permitted.)
EV Charging
Normal city parking requirements were waived for this project. Therefore, there is no car parking on the site and no corresponding provision for an EV-charging infrastructure.
(Left, Opposite Page) Commu- nity cafe at the building corner adjacent to the paseo and In Chan Kaajal Park.
(Above) Heat pump water heater located on the roof.
26 Colmac HPA 15-PDAC PLC
27 See Case Study No. 1, Ivy Senior Apartments, p. 17, for additional discussion of this issue.
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