The two bottom rows of PV panels in the photo are Phase II of a three-phase, 36 kW, solar demonstration project to highlight three different types of solar PV technology, educate the public and generate power for Western’s Folsom facility. Phase II consists of 320 Energy Photovoltaics Inc., EPV 40 thin film amorphous silicon modules rated at 40 watts peak per module. Eight modules are connected in parallel to a fused combiner box.

A total of 40 combiner boxes are divided among five Trace 4048 inverters (eight boxes per inverter). The inverters boost the DC output of about 44 volts to 240 volts AC. The inverter output is then boosted by a transformer to 480 volts AC, three-phase, for connection to the building’s electrical system.

Facility information

• System & Building Owner: Western Area power
• Site Location: Folsom, CA

Electrical Design

• AC Output:  240 V
• PV Configuration (per string): 8 parallel
• Number of strings: 40
• DC Current: 58 A at each inverter
• DC Voltage: 44 Vmp at each inverter
• Total number of inverters: 5

Schedule

• Installation Completed: September 1999
• Construction Duration: 6 days

Performance Parameters

• Peak Power Capacity: 12.8 kW DC; 10.2 kW AC
• Annual Energy (est.):  26,900 kWh/year
• Lifetime CO,Savings: 720 tons

PV Modules

• PV Cell Material: Thin film amorphous silicon
• PV manufacturer: Energy Photovoltaics
• PV Model: EPV 40
• Module size: 25″ x 49″

Contractors

• System integrator: SMUD
• Installer: Solar Electrical Systems