This article was written by Matt Bray and Garren Sparks.
Recently the Bureau of Land Management contracted with SERC to design and install a photovoltaic (PV) system for the Kaluna Cabin. Located in California’s rugged King Range National Conservation Area in southwestern Humboldt County, the Kaluna Cabin overlooks the Kaluna cliffs and the mighty Pacific Ocean. Acquired by BLM in the 1990’s, the cabin is used to showcase the natural beauty and ecological importance of the area to visiting government officials, dignitaries, and non-profit groups. The cabin has no electricity, and propane is used for lighting, refrigeration, hot water, and cooking. BLM staff decided that an off-grid PV system to provide electricity for lighting and small electronics could improve the usability of the cabin as well as decrease fire hazards associated with using propane for lighting.
The goals of the PV system design are to provide lighting and the ability to run low load electric devices. The BLM already has some surplus PV equipment originally procured for a previous project, including eight 75-Watt modules, a charge controller, and a DC load center. To evaluate the condition of the unused modules after eight years in storage, we performed current- voltage (IV) curves for each module using SERC’s new PV module testing station. All modules performed well, generating around 10% below manufacturer rated output, which is common even for new modules.
With help from SERC student research assistants Patricia Lai and James Apple, we have produced a range of PV system design options offering various levels of lighting and small appliance capacity. One design also provides enough power to permit replacement of the propane refrigerator with an efficient electric model. BLM is in the process of selecting one of our designs, and installation is scheduled for completion in late August. We will also develop an interpretive sign for BLM that will inform Kaluna visitors about how the system works and the environmental benefits of using solar.