Glass-to-Transparent Backsheet vs. Glass-to-Glass Solar Modules: A Detailed Comparison

In the world of photovoltaic (PV) technology, solar module design plays a crucial role in determining the efficiency, durability, and overall performance of solar power systems. Two popular configurations are glass-to-transparent backsheet and glass-to-glass solar modules. Each has its own unique features, advantages, and trade-offs that cater to specific applications and environmental conditions.

1. Structural Composition

Glass-to-Transparent Backsheet Modules:

• These modules consist of a front glass layer and a rear polymer-based transparent backsheet, typically made from materials like Tedlar or PET (polyethylene terephthalate). The transparent backsheet allows for some light to pass through, which is beneficial for bifacial modules.

• The light weight of these modules makes them easier to handle during transportation and installation, reducing overall costs. They are widely used in residential and small-scale commercial projects due to their affordability and ease of installation​

  
  

Glass-to-Glass Modules:

• These modules feature glass on both the front and back, sandwiching the solar cells between two layers of heat-treated, tempered glass. This design enhances the module's mechanical strength and protects the solar cells from environmental factors like moisture, dust, and corrosion.

• Glass-to-glass modules are especially known for their durability and resilience, making them ideal for large utility-scale projects and installations in harsh environments, such as deserts, coastal areas, or regions with heavy snowfall​.

  

2. Durability and Environmental Resistance

Glass-to-Transparent Backsheet Modules:

• While these modules offer decent durability, they are more vulnerable to degradation over time compared to glass-to-glass modules. The polymer backsheet can experience issues such as yellowing, cracking, or chalking after prolonged exposure to UV radiation and temperature changes​

  
  

• The transparent backsheet allows bifacial modules to capture some reflected light from the rear, increasing energy yield. However, their lifespan is typically shorter than glass-to-glass modules, with an expected lifetime of about 25 years​

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Glass-to-Glass Modules:

• Glass-to-glass modules boast superior durability and resistance to environmental stressors. The dual glass layers provide excellent protection against water ingress, UV degradation, and mechanical stress. This results in lower annual degradation rates (0.45% compared to 0.7% for glass-to-backsheet modules), ensuring better long-term performance​.

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• These modules are more suitable for extreme environments, as they can withstand high humidity, salt fog, and strong winds, which makes them ideal for coastal regions, deserts, and high-altitude areas​.

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3. Weight and Handling

Glass-to-Transparent Backsheet Modules:

• One of the key advantages of glass-to-transparent backsheet modules is their lighter weight, typically around 40 pounds (18 kg) per panel. This makes them easier to handle, transport, and install, reducing labor and logistical costs​.

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• Their lightweight nature is particularly beneficial for rooftop installations, where structural load capacity may be a concern.

Glass-to-Glass Modules:

• These modules are significantly heavier, averaging around 50 pounds (23 kg) due to the additional layer of glass. This increased weight adds complexity during transportation and installation, but it also contributes to their robustness and long-term stability​.

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4. Degradation and Performance

Glass-to-Transparent Backsheet Modules:

• These modules experience a higher degradation rate of about 0.7% per year. Over a typical 25-year lifespan, this results in a power output of around 80% of the initial performance​.

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• While they are more prone to micro-cracks and mechanical stress, they remain a cost-effective solution for many residential and commercial projects.

Glass-to-Glass Modules:

• With a lower degradation rate of 0.45% per year, glass-to-glass modules retain around 87% of their original performance even after 25–30 years. The glass back provides additional support, reducing the likelihood of micro-cracks and protecting the solar cells from potential-induced degradation (PID)​.

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• This durability translates into longer warranties and more reliable long-term performance, making glass-to-glass modules ideal for projects where longevity and reliability are paramount​.

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5. Cost and Aesthetic Considerations

Glass-to-Transparent Backsheet Modules:

• These modules are more cost-effective, especially for smaller projects, due to their lighter weight and simpler manufacturing process. Additionally, bifacial modules with transparent backsheets can achieve better aesthetics on residential rooftops by blending seamlessly with different architectural styles​.

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• However, they may not offer the same level of robustness as glass-to-glass modules, particularly in harsh environmental conditions.

Glass-to-Glass Modules:

• The additional glass layer increases the cost of these modules, but this investment is offset by their superior durability and long-term reliability. Their transparent nature makes them visually appealing for structures like pergolas, carports, and greenhouses, where light transmission is beneficial​.

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6. Applications and Suitability

Glass-to-Transparent Backsheet Modules:

• These modules are best suited for residential and light commercial applications, where cost and ease of installation are key priorities. They can be a good choice for bifacial applications in regions with lower environmental stress​.

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Glass-to-Glass Modules:

• Thanks to their resilience, these modules are ideal for utility-scale projects and installations in extreme weather conditions, such as deserts or high-humidity areas. Their transparency also makes them suitable for specialized applications like greenhouses, pergolas, and other architectural projects​

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Conclusion

In summary, glass-to-transparent backsheet modules are a practical, cost-effective solution for smaller, less demanding installations, offering lightweight convenience and aesthetic appeal. However, glass-to-glass modules provide enhanced durability, lower degradation rates, and superior performance in harsh environments, making them a solid choice for large-scale, long-term projects. The decision between the two ultimately depends on the specific requirements of the installation, including environmental conditions, budget, and long-term energy yield expectations.

What's an I-REC (International Renewable Energy Certificates)?

I-RECs as an instrument that allow businesses to procure this energy even in the countries that don’t have their own certification systems. Each I-REC represents proof that 1 MWh of renewable energy has been produced and takes into account the multiple environmental benefits that are equivalent to the RE generated via that one certificate by generating a unique ID for each I-REC.

An international renewable energy certificate (I-REC) represents transferrable proof that one MWh of electricity was produced from renewable energy sources and added to an electrical grid. Purchasing an I-REC allows the buyer to claim consumption of one MWh of renewable energy. I-RECs can originate from wind, solar, ocean energy, biomass, hydropower, landfill gas, aerothermal, geothermal, and landfill gas projects.

I-RECs as an instrument allow businesses to procure this energy even in the countries that don’t have their own certification systems. Each I-REC represents proof that 1 MWh of renewable energy has been produced and takes into account the multiple environmental benefits that are equivalent to the RE generated via that one certificate by generating a unique ID for each I-REC. This ID in return tracks the asset that has generated that RE, enabling the purchaser to cross-check the authenticity and quality of clean energy generated. Generated from an underlying RE asset, through this process I-RECs prevent double-counting, double issuing, and false claiming of emissions reductions at the source.

I-RECS offer companies and individuals a convenient way to offset their carbon footprint and transition to green energy by simply claiming the energy that comes from renewable sources & renewable energy attributes of that electricity. The end-consumer can avail, redeem or trade the issued I-RECs and benefit from the same simultaneously.

How does I-REC work ?

The RE generators can register their plants on the I-REC Registry by making an application along with a set of plant documents. The application is then validated by the Registry and they seek clarity (if required). After the validation, an independent audit may also be initiated by the Registry based on their discretion. Once the registration is approved by the Registry, the generator can furnish the meter readings from time to time to get I-RECs issued on the electricity generation from the RE asset. The end-consumer or a trader can then purchase the issued I-RECs and may redeem/retire or trade the certificates respectively. The revenue generated out of the sale of I-RECs can be put back into the system by the RE generator to finance development of new RE projects. In effect, the I-REC mechanism encourages development of new RE projects and reducing the carbon emissions across the world while passing on the benefit to the end-consumers.

How do I-RECs benefit businesses?

Some of the key benefits for businesses includes

• It helps in the reduction of carbon footprint of any organization, followed by less pollution generated in your everyday operations.

• It helps in mitigating climate change, I-RECs also support the overall renewable energy market by ensuring fair & reliable trade of RE.

• I-REC gives purchaser the freedom to choose where exactly they buy RE from, both the source and the supplier, from both local or international markets.

• It helps corporates to achieve their ESG goals, I-RECs give a competitive edge to your portfolio for their investors.

IRECs serve as a flexible and efficient tool to incentivize the growth of renewable energy capacity globally, facilitate investment in renewable energy projects, and help organizations and governments meet their sustainability and carbon reduction goals. They are an essential component of the global effort to transition to a more sustainable and low-carbon energy future.

#carbontrading #irec #renewableenergycertificates

Importance of ACDB & DCDB for Solar system Protection & Safety

ACDB & DCDB are vital protection devices for solar system safety & protection

ACDB (Alternating Current Distribution Box) and DCDB (Direct Current Distribution Box) are essential components in a solar power plant. They serve different functions in the solar energy system and are necessary to ensure the safe and efficient operation of the plant. Here are the requirements and functions of ACDB and DCDB in a solar plant:

DCDB (Direct Current Distribution Box):

• Input of Solar Panels: DCDB is connected directly to the solar panels, where it receives the DC power generated by the panels. Each string of solar panels is typically connected to a DC combiner box to consolidate the DC power output before it reaches the DCDB.

• Protection and Safety: DCDB includes various protective devices such as fuses, circuit breakers, surge protection devices, and isolators. These devices are essential to ensure the safety of the solar plant by preventing overcurrent, overvoltage, and short-circuits that can damage the panels or other components.

• Monitoring and Control: DCDB may also include monitoring and control devices such as string-level monitoring systems. These systems help detect any issues with individual strings of panels, enabling early detection and maintenance.

• DC to AC Inverter Connection: The DC power from the solar panels is fed into inverters, which convert it into AC power for use in the electrical grid. The DCDB facilitates the connection between the inverters and the DC source.

ACDB (Alternating Current Distribution Box):

• Output of Inverters: ACDB is connected to the output of the inverters, where it receives the AC power generated by the solar plant's inverters. The AC power is typically at a higher voltage and is ready to be sent to the grid or used on-site.

• Protection and Safety: Similar to the DCDB, ACDB includes protective devices such as circuit breakers and surge protection devices to safeguard the AC electrical system from overloads, short circuits, and voltage surges.

• Metering and Monitoring: ACDB may include energy meters and monitoring equipment to measure the amount of electricity generated by the solar plant. This data is crucial for billing purposes, monitoring system performance, and ensuring compliance with regulatory requirements.

• Grid Connection: ACDB is also responsible for facilitating the connection of the solar plant to the electrical grid. It may include synchronization equipment to ensure that the solar power is aligned with the grid's frequency and voltage.

• Distribution: In larger solar plants, ACDB may also be involved in distributing the generated power to various loads within the facility, such as buildings, equipment, or storage systems.

In summary, ACDB and DCDB are essential components of a solar power plant's electrical infrastructure. They play a crucial role in ensuring the safe and efficient operation of the plant, protecting equipment, facilitating grid connection, and providing necessary monitoring and control capabilities. The specific requirements for ACDB and DCDB may vary depending on the size and complexity of the solar installation and local electrical codes and regulations.

#acdb #dcdb #safety #protection #solar #wattscore