LONGi 640W Bifacial Solar Panel

LONGi 640W Bifacial Solar Panel Overview

The LONGi 640W Bifacial Solar Panel is designed for solar projects that require high power output from each installed module. Its back-contact (BC) cell technology and bifacial construction make it suitable for installations where both front-side sunlight and reflected light from the rear can contribute to electricity generation.

With a rated output of 640 watts and module efficiency of 23.7%, this panel can help installers make effective use of the available installation area. Its dual-glass construction, aluminium alloy frame and IP68-rated junction box support a durable module design for appropriately engineered solar installations.

The panel measures 2382 × 1134mm and weighs 33.5kg. These dimensions are important when planning rooftop layouts, mounting structures, transportation and installation work.

For commercial and industrial buyers in Pakistan, selecting a solar panel involves more than comparing wattage. Electrical compatibility, roof space, temperature conditions, mounting design and long-term power degradation also affect the value of a solar installation.

Key Features and Benefits

BC Cell Technology

The BC cell technology used in this LONGi solar panel is an important part of its design. Back-contact cell architecture places electrical contacts on the rear side of the cell, helping create a front surface designed to capture sunlight effectively.

For buyers, cell technology is one factor to consider when comparing solar panels. Actual system output will also depend on installation conditions, shading, temperature and the electrical design of the complete solar system.

Bifacial Energy Generation

A bifacial solar panel can generate electricity from both its front and rear surfaces. The front receives direct sunlight, while the rear can capture reflected and scattered light from the surrounding surface.

The LONGi 640W model has a 70±5% bifaciality rating. The additional energy available from the rear side depends on the installation environment, mounting height, surface reflectivity, shading and the amount of light reaching the rear.

Light-coloured surfaces and suitable mounting arrangements may improve rear-side energy capture. However, additional generation is not fixed and should not be treated as a guaranteed percentage for every installation.

High Module Efficiency

The panel offers 23.7% module efficiency at its rated 640W output. Higher module efficiency can be useful when installation space is limited because it allows more rated power to be installed within a given panel area.

For commercial rooftops and industrial projects, efficiency should be assessed alongside panel dimensions, electrical characteristics, structural limitations and the inverter’s input requirements.

Dual-Glass Construction

The module features 2.0 + 2.0mm semi-tempered dual glass and an anodized aluminium alloy frame. This construction is relevant for installations where module durability and structural design are important considerations.

Correct handling, mounting, clamping and installation procedures remain essential to protect the panel throughout its service life.

Low Power Degradation

The panel’s power warranty includes a first-year power degradation allowance of less than 1%, followed by 0.35% annual degradation from year two through year 30.

Lower annual degradation helps maintain a greater proportion of the panel’s rated output over time. Actual electricity production will still vary with sunlight, temperature, dust, shading and system maintenance.

Best Applications for LONGi 640W Bifacial Solar Panel

This panel may be suitable for:

• Commercial solar rooftops requiring high-wattage modules.
• Industrial solar installations with appropriately designed mounting structures.
• Large solar power systems where module count and array layout affect project economics.
• Bifacial solar installations with suitable rear-side light exposure.
• Space-conscious solar projects where module efficiency is an important selection factor.
• Solar installers and project developers seeking high-output modules with defined electrical characteristics and long-term power warranty coverage.

Final suitability depends on the site’s electrical, structural and environmental requirements.

When Another Solar Panel May Be More Suitable

The LONGi 640W Bifacial Solar Panel may not be the right choice for every installation.

A different module design may be more suitable when:

• The available roof space cannot accommodate the panel’s dimensions.
• The mounting structure cannot safely support the module’s weight and design loads.
• The inverter has incompatible voltage or current limits.
• The project requires a different panel configuration or mounting arrangement.
• Rear-side light exposure is very limited and the project’s financial calculations depend heavily on additional bifacial generation.

Installers should evaluate the complete system design instead of selecting a panel on wattage alone.

Cell and Module Technology

What Is a Bifacial Solar Panel?

A bifacial solar panel is designed to receive light on both sides of the module. Its front surface captures direct sunlight, while the rear surface can use reflected light from the ground, roof or other surrounding surfaces.

The amount of additional electricity produced depends on installation conditions. Rear-side shading, mounting structure design, surface reflectivity and panel height can all influence bifacial performance.

How Do Bifacial Solar Panels Work?

The panel converts incoming sunlight into direct-current electricity. When reflected light reaches the rear surface, it can contribute to additional electrical generation.

To benefit from this design, the installation should allow suitable light to reach the rear side. Placing a bifacial module directly against an opaque surface can limit this advantage.

Why Module Dimensions Matter

The LONGi panel measures 2382 × 1134 × 30mm. Installers should account for these dimensions when calculating roof coverage, spacing, access pathways and mounting arrangements.

Panel layout must also consider cable routing, shading between rows, wind exposure and safe access for maintenance.

Technical Specifications

Performance and Power Degradation

The LONGi 640W Bifacial Solar Panel combines a high rated output with a long-term power warranty structure.

Its power degradation figures are:

• First-year degradation: Less than 1%.
• Annual degradation from year two to year 30: 0.35%.

The power warranty graph indicates a minimum warranted output of approximately 88.85% at year 30.

These figures help buyers evaluate long-term power retention. They do not represent a guarantee of annual electricity production, which depends on sunlight, installation orientation, operating temperature, shading, dust and other system conditions.

The temperature coefficient of maximum power is −0.260%/°C. As cell temperature rises above the reference temperature, module power output generally decreases. Proper mounting and ventilation can help manage operating temperatures.

Performance Considerations for Pakistan

Pakistan’s solar installations can experience high summer temperatures, dust accumulation and seasonal changes in sunlight. These conditions make proper system design and maintenance important.

High Summer Temperatures

The panel’s negative maximum-power temperature coefficient means that its power output can decrease as cell temperature rises. Installers should provide appropriate mounting clearance and ventilation where the installation design allows it.

Dust and Cleaning

Dust can reduce the sunlight reaching the cells. Periodic inspection and appropriate cleaning help maintain generation, particularly in dusty areas. Cleaning methods should follow safe solar-panel maintenance practices.

Bifacial Installation Design

For better rear-side energy capture, installers should consider mounting height, ground or roof reflectivity, structural shading and the arrangement of nearby panels.

Electrical Compatibility

The module’s 53.60V open-circuit voltage and 15.09A short-circuit current are important when designing solar strings. Voltage can rise in colder conditions, while current limits must be checked against the selected inverter.

The installer should calculate string voltage under the expected temperature range and confirm that the inverter’s maximum DC voltage, MPPT range and input-current limits are respected.

LONGi 640W Bifacial Solar Panel Price in Pakistan

The LONGi 640W Bifacial solar panel price in pakistan is an important consideration for buyers planning a residential, commercial or industrial solar installation.

The current price of the LONGi 640W Bifacial Solar Panel in Pakistan is Rs. 27,136 per panel.

The overall cost of a solar project depends on the number of panels, mounting structure, inverter capacity, protection equipment, wiring, installation requirements and other system components.

Dealers, installers and bulk buyers can contact Hajvery Solar Energy to enquire about current availability and quantity-based pricing.

LONGi 640W Bifacial Solar Panel: Tier 1, A-Grade and Authenticity

When buying a solar panel, consider the exact model identification, physical condition, serial information and applicable warranty.

Tier 1 status should be assessed using current, reliable evidence relevant to the manufacturer and purchasing requirements. It should not be inferred from wattage or brand name alone.

Similarly, A-Grade should only be used when the actual product’s condition and grading have been verified.

Before placing a bulk order, confirm that the delivered modules match the ordered model and that the warranty coverage applicable to the purchase is clear.

Hajvery Solar Product Verification

Hajvery Solar Energy can help buyers identify the correct product and review important purchasing details before ordering.

For the LONGi 640W Bifacial Solar Panel, buyers should check:

• The exact model code: LR7-72HVD-640M.
• The rated power and electrical characteristics.
• The physical condition of the module.
• The applicable product and performance warranty.
• Compatibility with the planned inverter and mounting structure.

For larger installations, the complete system design should be reviewed before purchasing the required number of modules.

You can verify your LONGi 640W Bifacial Solar Panel through Hajvery Solar Energy before purchasing. Check the exact model number and product details to help ensure you are buying the intended panel. The link for panel verification is given below:
LONGi 640W Bifacial Solar Panel verification.

Warranty

The LONGi 640W Bifacial Solar Panel has a 15-year warranty for materials and processing and a 30-year warranty for extra linear power output.

These are separate warranty coverages: the materials and processing warranty addresses the product, while the linear power warranty relates to long-term power output.

Buyers should confirm the applicable warranty terms, claim requirements and coverage conditions with Hajvery Solar Energy before ordering.

Before You Buy

Before purchasing the LONGi 640W Bifacial Solar Panel, consider the following:

• Power requirement: Calculate the total solar array capacity needed for the project.
• Roof or ground space: Confirm that the installation area can accommodate the module dimensions.
• Inverter compatibility: Check voltage, current, MPPT range and maximum system limits.
• Bifacial performance: Assess rear-side light exposure and the reflectivity of the installation surface.
• Mounting structure: Confirm structural capacity and suitable clamping arrangements.
• Operating temperature: Consider ventilation, heat and the panel’s temperature coefficient.
• Warranty: Review the applicable product and power warranty conditions.
• Quantity and availability: Confirm the current price and available quantity before placing an order.

Frequently Asked Questions

1. What is the LONGi 640W Bifacial Solar Panel price in Pakistan?

The current price of the LONGi 640W Bifacial Solar Panel in Pakistan is Rs. 27,136 per panel. Contact Hajvery Solar Energy to confirm current availability and bulk-order pricing.

2. What is the efficiency of the LONGi 640W Bifacial Solar Panel?

The panel has a 23.7% module efficiency, which can help make effective use of available installation space.

3. What does bifacial mean in a solar panel?

A bifacial panel can generate electricity from both its front and rear surfaces. Rear-side generation depends on reflected light, mounting height, surface reflectivity and shading conditions.

4. What are the dimensions of the LONGi 640W solar panel?

The module measures 2382 × 1134 × 30mm and weighs 33.5kg.

5. What is the model number of the LONGi 640W Bifacial Solar Panel?

The exact model is LR7-72HVD-640M.

6. What warranty does the LONGi 640W Bifacial Solar Panel have?

It has a 15-year warranty for materials and processing and a 30-year warranty for extra linear power output. Applicable terms and claim requirements should be confirmed before purchase.

7. Is the LONGi 640W Bifacial Solar Panel suitable for commercial installations?

It may suit commercial rooftops and industrial solar projects where its dimensions, electrical limits, mounting requirements and bifacial characteristics fit the installation design.

8. How do I check inverter compatibility?

Check the panel’s open-circuit voltage, operating voltage, short-circuit current and operating current against the inverter’s maximum DC voltage, MPPT range and current limits. A qualified installer should also account for temperature-related voltage changes and string configuration.

Buy LONGi 640W Bifacial Solar Panel from Hajvery Solar Energy

Choose Hajvery Solar Energy for solar product enquiries, purchasing guidance and help reviewing your installation requirements.

Whether you are planning a commercial rooftop project or a larger solar installation, confirm the exact panel model, quantity, current price and applicable warranty before ordering.

For mor options, View LONGi Solar Panel In Pakistan.