Accelerating the solar-thermal energy storage via inner-light supplying with optical waveguide.

Area of Science:

• Materials Science
• Renewable Energy Engineering
• Optics

Background:

• Solar-thermal energy storage is crucial for renewable energy utilization.
• Phase-change materials (PCMs) are widely used but suffer from low thermal conductivity, limiting charging rates and efficiency.
• Traditional surface irradiation methods can lead to overheating and reduced performance.

Purpose of the Study:

• To develop a novel method for enhancing solar-thermal energy storage efficiency.
• To overcome the limitations of low thermal conductivity in PCMs.
• To improve the solar-thermal conversion efficiency and charging rate of PCM systems.

Main Methods:

• Proposed an inner-light-supply mode using side-glowing optical waveguide fibers to transmit sunlight directly into a paraffin-graphene composite PCM.
• Regulated the solar-thermal conversion interface in the spatial dimension.
• Tested the large-scale device in outdoor conditions.

Main Results:

• The inner-light-supply mode accelerated the charging rate by 123% compared to traditional surface irradiation.
• Achieved a solar thermal efficiency of approximately 94.85%.
• Demonstrated efficient outdoor operation of the large-scale device.

Conclusions:

• The inner-light-supply strategy effectively enhances solar-thermal energy storage by addressing PCM limitations.
• This method offers a significant improvement in charging rate and conversion efficiency.
• The technology shows strong potential for practical, large-scale solar-thermal energy applications.