Page 122 - Designing for Zero Carbon-Volume 2_Case Studies of All-Electric Multifamily Residential Buildings

CASE STUDY NO. 5
CASA ADELANTE AT 2060 FOLSOM
Renewable On-Site Energy Supply
Solar Photovoltaic System
Since the nine-story building covered the entire site, the only space available for a solar photo- voltaic system was the limited area of the roof. Even after accommodating the space require- ments of the mechanical equipment such as the heat pump water heaters and the diesel gen- erator, however, the designers fit a system consisting of 212 Sunpower16 panels into the space available, for a total installed 76.3kW. (See Roof Plan on p.102 and drone photo below.)
The solar photovoltaic system generates electricity that is sent into the utility grid and is metered separately from the energy loads of the building. This energy is credited as an offset to the build- ing’s electric charges for the energy used in the common spaces and by the domestic hot water heat pump that serves the building as a whole. The utillity meters that record the energy used by all the spaces in the building are separate from that recording the energy produced by the solar PV system.
Sub-metering the building space energy use allows the building management to allocate some fraction of the utility charge to each tenant as appropriate.
16 Sunpower X22-360-COM, 360W, Monocrystalline.
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Designing for Zero Carbon: Volume 2