When choosing a solar street light with panel, one of the components that is considered is the solar panel. People are usually more focused on the wattage and efficiency of the solar panel and mostly overlook 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. For the fundamentals of how these systems work, our guide on the solar street light working principle is a helpful companion read.
Understanding the Difference Between the Solar Panel Glass Used in Different Solar Panels
The solar panel glass used in a solar street light with 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. Learn more about the technology in our post on what photovoltaic street lights are.
For crystalline panels, the solar panel glass is usually tempered glass ranging from 3 to 4 mm in thickness. Thicker glass means more stability; however, cheaper solar panels could have thin glass in the range of 2.5 mm. 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 of chemical or thermal processes. It is also called toughened or safety glass; it hardly breaks, and if it does break, it only breaks into smaller pieces rather than shards.
The Properties a Solar Panel Glass Should Have
The quality of the solar panel glass directly determines how well your solar street light with panel performs over its lifetime. Here are the key properties to look for.
Highly Transmissive
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 achieve mechanical stability and higher efficiency of the solar street light with panel.
Safety and Strength
Solar panel 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 a solar street light with panel. This is one of the key markers of a quality product, much like the 5 benefits of IP65 solar street lights point to durable weatherproofing.
Durability
As the front cover of the PV cells, you will expect solar panel glass to be highly durable to offer long-term protection for the solar panel. A durable solar panel glass shields the cells from hail, debris, and temperature swings, ensuring your solar street light with panel keeps performing year after year.
The Weight of Solar Panel Glass
Although the solar panel glass is heavy, with a typical 250W solar panel weighing about 20 kg, a lot of solar manufacturers see this as a necessity, as glass is the current standard in the solar industry. However, experts are seriously working on reducing the weight to produce very light solar panels. A lighter solar street light with panel would be easier to install and mount on poles or walls. Our 9 factors for choosing solar power light poles can help you match a panel to the right pole.
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. 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. If your panel is underperforming, our guide on 5 ways to fix a solar light not working can help you diagnose the issue.
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 solar street light with panel that makes use of tempered glass; it will be specified in 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. For a broader buying checklist, see our list of the 10 things about the best solar street lights.
Frequently Asked Questions (FAQs)
1. Why is the solar panel glass important in a solar street light with panel?
The solar panel glass in a solar street light with panel protects the PV cells from dirt, moisture, and rain, provides low reflection for better light absorption, strengthens the panel, and ensures high transmissivity. Quality glass directly affects the panel’s efficiency, yield, and lifespan.
2. What type of glass is best for a solar street light with panel?
Tempered glass is the best choice for a solar street light with panel. It is around six times stronger than flat plate glass, resists breakage, and when it does break, it shatters into small harmless pieces rather than sharp shards. It’s typically 3 to 4 mm thick on quality crystalline panels.
3. What happens if a solar street light with panel uses cheap glass?
Cheap glass on a solar street light with panel tends to cloud over time, which reduces the panel’s efficiency. It also breaks easily, creating safety risks. Even a minor crack can allow water to penetrate the panel, potentially causing a fire hazard.
4. What is an antireflective (AR) coating on a solar street light with panel?
An antireflective (AR) coating is a film applied to the solar panel glass of a solar street light with panel before tempering. It reduces reflected light and increases the amount of sunlight absorbed by the PV cells, improving both mechanical stability and overall efficiency.
5. How can I tell if a solar street light with panel has quality glass?
Look for a solar street light with panel that specifies tempered glass in its description and carries IEC and UL 1307 certifications, which confirm the panel has passed safety tests. These markers indicate durable, high-transmissivity glass likely to last for many years.