When choosing a solar street light with solar panel, one of the components that are considered is the solar panel. People are usually more focused on the wattage and efficiency of the solar panel and mostly overlooking the kind of solar panel glass used in the solar panel. However, this part of the solar panel is equally as important as other parts as it gives protection to the PV cells against detrimental environmental elements like dirt, vapor, rain, etc. Additionally, it also provides low reflection, makes the solar panel stronger, and offers high transmissivity.
Understanding the difference between the solar panel glass used in different solar panels
The solar panel glass used in solar street light with solar panel differs according to the type of solar panel. For thin (amorphous) solar panels, the glass usually used is the flat plate glass. Sometimes this type of solar panel glass is found in low cost polycrystalline and monocrystalline solar panels. A lot of thin-film solar panels utilize flat plate solar panel glass because of the way they are designed. The amorphous solar panels are created using one or more thin layers of PV materials, which are placed on a steel or glass plate. To get past this relative weakness, certain companies use the thicker flat plate glass. However, the tempered glass is stronger.
For crystalline panels, the solar panel glass is usually tempered glass ranging from 3 to 4mm in thickness. Thicker glass means more stability, however, cheaper solar panels could have thin glass in the range of 2.5mm. In crystalline panels, the surface of the glass is rough to allow EVA film to bond properly with the solar panel glass when lamination is done. The tempered solar panel glass is six times stronger than the flat plate glass, it is manufactured through the use chemical or thermal. It is also called toughened or safety glass, it hardly breaks and if does break, it only breaks into smaller pieces rather than shards.
The properties a solar panel glass should have
The solar panel glass used in your solar street light with panel is crucial to the panel effectiveness and total yield of the whole solar street light system. The right solar panel glass will make sure there is a great solar radiance transmittance as the main duty of a solar panel glass is to help ensure sunlight is transmitted as much as possible into the fixture. The quality of a very transmissive glass directly affects the yield and performance of the solar panels.
Antireflex (AR) coating
This coating is combined with the solar panel glass using a layer of the antireflective film just before the tempering of the glass. This added coating ensures that the level of reflected light is reduced and the percentage of the sunlight that is absorbed by the PV cells is increased. This helps achieves mechanical stability and higher efficiency of the solar street light with panel.
Safety and Strength
Solar panels manufacturers prefer tempered glass for quality solar panels and the reason is clear, the special make and characteristics of the glass make it the best option to use in solar street light with panel.
As the front cover of the PV cells then you will expect solar panel glass to be highly durable to offer long-term protection for the solar panel.
The Weight of solar panel glass
Although the solar panel glass is heavy with a typical 250W solar panel weighing about 20kg. A lot of solar manufacturer sees that has a necessity as glass is the current standard in the solar industry. Although, experts are seriously working on reducing the weight to produce very light solar panels.
The dangers of cheap solar panel glass
The solar panel is a delicate accessory of your solar street light with panel. This is why care should be taken to make sure the solar panel that comes with the street light is not made from cheap glass. The downside of using cheap glass in the making of solar panels is the issue of clouding over time. When glass gets clouded, the efficiency of the solar panel reduces seriously. Apart from that, cheap glass can get broken easily, which can cause serious safety issues. Just a minor crack in the glass can cause fire hazards due to the penetration of water into the solar panel.
Solar Street Light with Panel: Conclusion
So no matter the type of solar panel you choose be it polycrystalline, thin-film or monocrystalline, ensure the type of glass on the solar panel is of the best quality. Go for a panel that makes use of tempered glass, it will be specified on the panel description. Solar panels with IEC and UL 1307 certificates indicate that they have undergone safety tests and passed. These types of panels are very likely to last for a long time on your solar street light with panel.
Check out our article on Cost-effective and Extremely Efficient Four Types of solar powered outdoor street lights.