Page 158 - Solar Power in Building Design The Engineer's Complete Design Resource

128 SOLAR POWER GENERATION PROJECT IMPLEMENTATION

Figure 5.8 Boron solar farm inverter system. Photo courtesy of Grant
Electric.

Project description This project is located in Hemet, California, an hour-and-a-
half drive from downtown Los Angeles. The project consists of a 150-acre campus
with a Water Education Museum, sponsored by the Metropolitan Water District and
the Water Education Board; an Archaeology and Paleontology Museum, sponsored
by the City of Hemet; several lecture halls; a bookstore; a cafeteria; and two audito-
riums. In this installation, PV panels are assembled on specially prefabricated sled-
type support structures that do not require roof penetration. Roof-mount PV arrays
are strapped together with connective ties to create large island platforms that can
withstand 120-mi/h winds. A group of three PV assemblies with an output power
capacity of about 6 kW are connected to a dedicated inverter. Each inverter assembly
on the support incorporates overcurrent protective circuitry, fusing, and power col-
lection busing terminals.
The inverter chosen for this project includes all technology features, such as anti-
islanding, ac power isolation, voltage, and frequency synchronization required for grid
connectivity. In addition, the inverters are also equipped with a wireless monitoring
transmitter, which can relay various performance and fault-monitoring parameters to
a centrally located data acquisition system. Figure 5.9 is a photograph of a section of
the roof mount solar power cogeneration system and Figure 5.10 a section of roof
mount inverter installation at Water and Life Museum, Hemet California.
Strategically located ac subpanels installed on rooftops accumulate the aggregated
ac power outputs from the inverters. Outputs of subpanels are in turn accumulated