Shared on September 04, 2012 written by Keith McRae
Operating Wireless Gateways & Cellular Routers Off-Grid with Solar PV Electric
Part 2: Solar PV Panel & Mount
The Solar photovoltaic panel harvests electricity from the sun. Quality and efficiency vary widely from manufacturer to manufacturer. Panels often use polycrystalline silicon, monocrystalline silicon, amorphous silicon, cadmium telluride, and copper indium (di)selenide/sulfide (CIGS). CIGS has the highest absorption coefficient of solar modules and is useful in harvesting energy in sub-optimal conditions such as on cloudy and overcast days and has high efficiency and carry a high cost per watt. Monocrystalline thin film solar cells are often more expensive than multi-¯crystalline or polycrystalline based cells, but have a greater efficiency which is useful for wireless off-grid installations and provide a balanced price to performance.
While researching ratings be mindful of whether the wattage is rated as PTC or STC. PTC or PVUSA Test Conditions uses a known constant developed by NREL (National Renewable Energy Labs). STC, or Standard Test Conditions, uses a methodology which produces higher results. Generally PTC is held to be more reflective of real-world solar and climatic conditions.
Understand the efficiency of the panel. On a pole mounted system , an efficient panel should be used to ensure that the system can be powered by one or two panels.
The panel must have its performance characteristics available, and these should follow a known standard such as PTC mentioned above.
PV Panel Mount
For the panel installation pole mounts will house up to a certain Watt size in a single panel for a compact pole mount installation. These can be installed so the pole has two panels with minimal shading impact on the lower panel. Larger panels may require different bracing for the pole and mount. Panels will install angled toward the equator. For North America, this array azimuth is 180 degrees, due south. You should have a clear access to the sun in a southerly facing mount. Other compass headings are feasible with a corresponding loss in productivity. Their pitch or array tilt angle is based on the location they are used in and how the system is optimized.
Continue reading Part 3: Solar PC Electric Operations of the full article.
Keywords: PV Panel Mount, Solar PV Electric Operations