Page 73 - Designing for Zero Carbon-Volume 2_Case Studies of All-Electric Multifamily Residential Buildings

VERA CRUZ VILLAGE CASE STUDY NO. 3
(Opposite Page) Installation of 384 solar PV panels on the roofs of canopies installed above five parking areas. (Photos courtesy of John Paul Lababit, SHE.)
Renewable On-Site Energy Supply
Solar Photovoltaic Systems
Phase 1 of the Vera Cruz Village project consisted of the construction of five structural canopies above some of the existing parking areas and the installation on the canopy roofs of 384 solar PV panels16 totaling 138 kW. The system was installed under a third-party Power Purchase Agreement (PPA), under which the contractor, Sunrun, manages and maintains the system for a defined period of time while selling the power generated to the individual tenants (93%) and the owner (7%) according to the terms of the Virtual Net Energy Metering (VNEM) arrangement. The contractor receives the tax credits and incentives for the system’s initial cost, while the tenants benefit from a lower rate for their electricity. The construction cost of the canopies was paid for by the owner and manager of Vera Cruz Village, Self-Help Enterprises, which had secured funding through the California Low-Income Weatherization Program (LIWP).
Solar electric meters, one for each point of connection of the solar PV arrays, are mounted in a visually-prominent location for ready observation and access (see photos below). The annual productivity of the solar PV system was modeled using PVWatts17 and was measured since it was fully operational in August 2020. In 2022, the system produced 151,133 kWh, with 141,309 kWh credited to the individual apartments. These results are shown in the graph on p. 64, which also includes the aggregate total electric energy used by all the apartments. As this graph in- dicates, about 35% of the energy consumption was provided by the solar PV system that year.
16 LONGi Solar, model type LR6-72PH-360M (360 watts-DC each). Solar Edge P400 Optimiz- ers / Optimizers: (9) Solar Edge 11400H-US + (1) Solar Edge 3800H-US
17 https://pvwatts.nrel.gov/
(Below) Electric meter installa- tion for the site solar PV sys- tem installed on five canopies.
Designing for Zero Carbon: Volume 2
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