Solar Controllers--Don't be a Sucker! :(
Just got to say it again, how it is we are sitting here for five months off grid on solar with no problems at all (third season on solar like this), using the non-programmable, non-MPPT, solar control...
Forum Discussion
Extract:
Test results show nearly identical relative light transmission plots for all five test modules with glass superstrate regardless of the type of PV cell technology. (This project tested monocrystalline silicon, polycrystalline silicon, amorphous silicon, cadmium telluride, and copper indium gallium selenide). This indicates that the reflective losses are governed almost exclusively by the air-glass interface of the PV modules.
The relative light transmission plots obtained using the IEC 61853-2 model were in good agreement with the plots obtained using the theoretical air-glass interface models and the empirical model developed by Sandia National Laboratories for the glass superstrate PV modules.
The standard states that “for the flat glass superstrate modules, the AOI test does not need to be performed, rather, the data of a flat glass air interface can be used." The results obtained in the current study validate this statement.
http://www.solarabcs.org/about/publications/reports/aoi/
IEC 61853-1 and IEC 61853-2 Standards: Validation of Models using Outdoor Test Methods
Photovoltaic Module
Power Rating per
IEC 61853-1 Standard:
A Study Under Natural Sunlight
The above is IEC 61853-1. Validation of Draft International Electrotechnical Commission 61853-2
Standard:
Angle of Incidence Effect on Photovoltaic Modules discusses -2 which addresses angle on incidence.
Notice figure E1 for example shows 40% of solar irradiance is still available at an angle of 70 degrees (where straight on is 0 degrees). This is without front panel reflection and presumably without the extra atmospheric attenuation at sunrise and sunset, but it is a real eye opener. So for example a vertical wall mounted panel could collect significant power even at solar noon if the sun in 20 degrees south of vertical.
I'd still like to get access to the actual IEC 61853-2 if anyone has it. I want to check the tech library at work to see if we have it.
Jim
Test results show nearly identical relative light transmission plots for all five test modules with glass superstrate regardless of the type of PV cell technology. (This project tested monocrystalline silicon, polycrystalline silicon, amorphous silicon, cadmium telluride, and copper indium gallium selenide). This indicates that the reflective losses are governed almost exclusively by the air-glass interface of the PV modules.
The relative light transmission plots obtained using the IEC 61853-2 model were in good agreement with the plots obtained using the theoretical air-glass interface models and the empirical model developed by Sandia National Laboratories for the glass superstrate PV modules.
The standard states that “for the flat glass superstrate modules, the AOI test does not need to be performed, rather, the data of a flat glass air interface can be used." The results obtained in the current study validate this statement.
http://www.solarabcs.org/about/publications/reports/aoi/
IEC 61853-1 and IEC 61853-2 Standards: Validation of Models using Outdoor Test Methods
Photovoltaic Module
Power Rating per
IEC 61853-1 Standard:
A Study Under Natural Sunlight
The above is IEC 61853-1. Validation of Draft International Electrotechnical Commission 61853-2
Standard:
Angle of Incidence Effect on Photovoltaic Modules discusses -2 which addresses angle on incidence.
Notice figure E1 for example shows 40% of solar irradiance is still available at an angle of 70 degrees (where straight on is 0 degrees). This is without front panel reflection and presumably without the extra atmospheric attenuation at sunrise and sunset, but it is a real eye opener. So for example a vertical wall mounted panel could collect significant power even at solar noon if the sun in 20 degrees south of vertical.
I'd still like to get access to the actual IEC 61853-2 if anyone has it. I want to check the tech library at work to see if we have it.
Jim
