Inspection and Short-Term Measurement of a National Park Service Photovoltaic/Fuel Cell Remote Hybrid Power System at Kirby Cove, California: Preprint

This paper reports short-term performance measurements of a hybrid photovoltaic/fuel cell power supply system at Kirby Cove Campground, Golden Gate National Recreation Area, California. The system operated reliably for two years from June 1999 to June 2001. A combination of solar power and power from the fuel cell supplied the campground host power load. In 2001, reports of power outages promptedan investigation. Data are reported for 13.5 days from September 2 to September 15, 2001. Over this time, the photovoltaic array delivered 42.82 kWh, the fuel cell delivered 1.34 kWh, and the net energy from the battery was 6.82 kWh. Photovoltaic efficiency was measured at 8.9%, and fuel cell efficiency at 42%, a typical value. But fuel cell power output was only 35 W, not 250 W, the rated power. Replacing a burnt fuse restored fuel cell power to 125 W, but several cells had low voltage, so the fuel cell was removed for repair or replacement. After the fuel cell failed, loads exceeding the solar capability discharged the batteries; the total for the eight power outages was 48 hours. This paper describes the system's daily operation, presents performance indicators, identifies somecauses of performance degradation, and recommends improvements.