Solar modules without glare – ideal for any environment
Megasol solar glasses are low-reflection and ensure glare-free operation in most installation situations. Nevertheless, glare protection is a crucial aspect in the planning of photovoltaic systems, because in rare cases, disturbing glare can occur. For challenging installation situations, Megasol offers PV modules with different glass structures and/or a ‘ZeroReflect+’ surface – ideal for densely built-up areas or systems near airports and roads.
Understanding glare: an overview of factors and intensity
Every surface reflects light – but how strong the glare actually is depends on various factors:
- The material surface and the angle of the sun influence the reflection.
- Duration and luminance determine the subjective impression.
Even roof tiles can, depending on their surface, have a comparable blinding effect to a roof window, for example. The light intensity is given in candela per square metre (cd/m²). Values between 50 000 and 100 000 cd/m² are perceived by the human eye as blinding. By way of comparison: the luminance of a PC monitor is 250 cd/m², and the midday sun in an unclouded sky is 1 600 000 000 cd/m².
When do solar modules cause glare?
Megasol's solar glasses are low-reflective and do not cause glare in most installation situations. However, with the increasing installation of solar panels in densely built-up areas, on street-side facades or near airports, the issue of glare is becoming more and more important – not only for personal comfort, but also for public safety. In some regions, photovoltaic systems may even require a permit and be subject to reporting requirements and an anti-glare report. Location factors that influence glare:
- Orientation: In addition to the south, east, west and north orientations are also common, which changes the angles of incidence and reflection.
- Slopes: The angle at which a system is viewed plays a crucial role.
- Dense development: Distance, viewing angle and the size of the system in the field of view influence the subjectively perceived glare.
Less reflection thanks to structured solar glasses
The glare from solar modules is mainly caused by the smooth glass surface. This is needed for a high light transmission. The light beam is reflected in a concentrated manner on this surface and thus, in the worst case, creates a blinding effect. Structured solar glasses provide a remedy here. The irradiation is reflected irregularly, the light beam is loosened (bundle widening) and thus more diffuse. The selective blinding effect is reduced. Megasol offers solar modules with different glass structures that additionally reduce reflections.
‘ZeroReflect+’ technology
The solar glasses ‘Fjord’ and ‘Ripple’ are also available with the ‘ZeroReflect+’ surface. This ‘ZeroReflect+’ technology is also used for MATCH Slate Creek Granite, which additionally highlights the slate look of the solar modules.
‘ZeroReflect+’ is a surface treatment specially developed in the Megasol technology laboratory that makes solar modules almost glare- and reflection-free – regardless of the installation situation, angle or time of day. It is used wherever the highest standards of glare control are required.
A coloured solar panel without an anti-reflective coating.
A colourful solar panel with ZeroReflect.
Megasol has its products tested
Megasol has had its glass tested by independent institutes:
- The SPF Institute for Solar Technology at the University of Applied Sciences of Eastern Switzerland and the IEM Institute for Energy and Mobility Research at the University of Applied Sciences in Bern tested the ‘Fjord’ solar glass and its ‘ZeroReflect’ version under laboratory and outdoor conditions.
- The results show that the ‘ZeroReflect’ glass significantly reduces the glare effect. Compared to the standard ‘Fjord’ glass, the luminance of the ‘ZeroReflect’ glass increases much more slowly and only reaches the value for possible glare (50 000 cd/m²) at an angle of incidence of almost 70°.
Megasol Fjord solar glass is perfect for most applications
The results of the laboratory tests show that, with almost perpendicular irradiation of a very bright light beam (100 000 lx) and an angle of incidence of 10°, the reflected luminance is 70 200 cd/m². Up to an angle of incidence of 30°, the luminance remains approximately at this value, only increasing from 40° and rising more sharply from 50°. In addition, there was only a very narrow reflection beam, and thus an overall limited glare effect, which only widens slightly above 40°. These test results show that Megasol solar modules with ‘Fjord’ glass hardly cause any glare in most installation situations and can generally be used for low-reflection solar systems.
Conclusion: the right solution for every installation situation
Megasol's low-reflection solar modules are perfect for most applications. For critical installation situations, we recommend the version with structured solar glass and/or ‘ZeroReflect+’ technology, which guarantees maximum freedom from glare.
