Client: Helio Power
Location: Fallbrook, CA
Lopez Engineering, Inc. (LEI), retained by Helio Power, designed an award-winning Photovoltaic system for Fallbrook Public Utility District. This 60 kW Photovoltaic System project provides renewable generation at the Fallbrook Public Utility District’s (FPUD) headquarters together with sophisticated metering and displays. These allow FPUD customers to see an operational system and become educated about photovoltaic systems and their benefits. It reduces current energy usage by approximately a third primarily during daily peak periods, which is the most expensive energy to generate. Two existing open carport roofs provided the module mounting area while the inverters and electrical panel boards were mounted to an interior wall.
Maintenance requirements are substantially reduced from those required in most electrical generation plants, transportation costs are also reduced. System design utilizes four hundred and fifty eight (458) photovoltaic modules, each rated for 148 watts at full power or 64 kW. For safety at the photovoltaic modules, safety switches rated for photovoltaic systems each connect to sixteen photovoltaic modules. Additional safety switches, located near the inverters, enable each inverter to be safely disconnected from the solar photovoltaic system. Each inverter feeds an electrical panelboard’s branch circuit breaker. Two electrical panelboards are required to collect the 16 photovoltaic module groups’ output with the smaller capacity panelboard feeding the larger capacity panelboard. This, in turn, feeds back to the main switchgear via a metered utility visible disconnect with disconnects on both sides of the meter. Underground, concrete encased ductbanks connect photovoltaic modules on the farther roof with their respective inverters and the larger electrical panelboard with the utility visible disconnect. Remaining connections are in surface mounted rigid conduit.