Bifacial Solar Module Light Conversion Layer

Solution Overview

Problem

Conventional solar cell modules, particularly mono-facial crystalline silicon modules, face limitations such as low power generation efficiency and high costs due to landscape and object shading, and traditional bifacial cell modules are costly due to the use of heavy glass for back sheets, which restricts widespread adoption.

Innovation Solution

A solar cell module structure incorporating a bi-layered sheet with a support layer and a light conversion layer containing fluorescent molecules and hydrogenated styrene elastomer resin, which enhances light transmittance, reduces weight, and improves adhesion and UV conversion efficiency, while allowing for both front and back-side light exposure in bifacial configurations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If glass is used for back sheet to achieve transparency for back-side exposure, then light transmittance is improved, but weight and cost increase

Engineering Contradiction:

Improvelight transmittanceVSAvoidmodule weight

Core Design Contradiction:

Illumination intensityVSWeight of moving object

Solution Approach 1:

The patent changes the material parameter from glass to transparent plastic substrate, maintaining optical transparency while significantly reducing weight. The plastic substrate achieves comparable light transmittance for back-side exposure but with much lower density, directly resolving the weight-transmittance contradiction.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent substitutes expensive glass with a more cost-effective transparent plastic substrate. This material replacement reduces both material cost and manufacturing complexity while maintaining the essential function of back-side light exposure, addressing the cost-transmittance trade-off.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

2Illumination intensity

If glass is used for back sheet to achieve transparency for back-side exposure, then light transmittance is improved, but module cost increases

Engineering Contradiction:

Improvelight transmittanceVSAvoidmodule cost

Core Design Contradiction:

Illumination intensityVSEase of manufacture

Solution Approach 1:

The patent substitutes expensive glass with a more cost-effective transparent plastic substrate. This material replacement reduces both material cost and manufacturing complexity while maintaining the essential function of back-side light exposure, addressing the cost-transmittance trade-off.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent changes the material parameter from glass to transparent plastic substrate, maintaining optical transparency while significantly reducing weight. The plastic substrate achieves comparable light transmittance for back-side exposure but with much lower density, directly resolving the weight-transmittance contradiction.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If traditional encapsulant is used to fix solar cell and provide insulation, then adhesion and protection are improved, but UV light transmission is blocked reducing power generation

Engineering Contradiction:

Improveadhesion and protectionVSAvoidUV light transmission

Core Design Contradiction:

ReliabilityVSIllumination intensity

Solution Approach 1:

The patent introduces a light conversion layer as an intermediary between the encapsulant and solar cell. This layer converts UV light to visible light, allowing the encapsulant to maintain its protective and adhesive functions while enabling UV light to reach the solar cell through wavelength conversion, thus resolving the protection-UV transmission contradiction.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent changes the light wavelength parameter through the light conversion layer. By converting UV light to visible light, the system allows UV radiation to penetrate the encapsulant (which blocks UV) and reach the solar cell, maintaining protection while enabling UV utilization for power generation.

Inventive Principle:

Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The proposed structure increases solar cell efficiency by converting UV light to visible light, reduces module weight and cost, and extends the lifespan of solar cell modules through improved encapsulation and insulation, enhancing power generation capabilities.

Implementation Method 1

the light conversion layer includes a fluorescent molecule and a hydrogenated styrene elastomer resin

Methodology Applied

Scientific EffectFluorescence: Fluorescence

Data Source

PatentUS9705020B2Sheet and module structure

Publication Date: 2017.07.11 IND TECH RES INST

AI summary

A module structure is provided, which includes a front sheet, a back sheet opposite the front sheet, and a solar cell disposed between the front sheet and the back sheet. A first encapsulate film is disposed between the solar cell and the front sheet, and a second encapsulate film disposed between the solar cell and the back sheet. One or both of the front sheet and the second sheet includes a support layer and a light conversion layer on the support layer, wherein the light conversion layer includes a fluorescent molecule and hydrogenated styrene elastomer resin. The light conversion layer is disposed between the support layer and the solar cell.