Work

Re-defining Non-tracking Solar Cell Efficiency Limits with Directional Spectral Filters

Year: 2025

Type: article

Abstract: Optical filters that respond to the wavelength and direction of incident light can be used to increase the efficiency of tracking solar cells. However, as tracking solar cells are more expensive to install and maintain, it is likely that nontracking solar cells will remain the main product of the (terrestrial) solar cell industry. Here we demonstrate that directional spectral filters can also be used to increase the efficiency limit of nontracking solar cells at the equator beyond what is currently understood by up to ∼0.5% (relative ∼1.8%). We also reveal that such filters can be used to regulate the energy output of solar cells throughout a day or year, and can reduce the thickness of the absorber layer by up to 40%. We anticipate that similar gains would be seen at other latitudes. As this filter has complex wavelength-direction functionality, we present a proof-of-concept design based on Luneburg lenses, demonstrating these filters can be realized. Our results will enable solar cells with higher efficiency and more stable output while using less material.

Source: ACS Photonics

DOI: 10.1021/acsphotonics.4c02181

Authors: Alan R. Bowman, Samuel D. Stranks, Giulia Tagliabue

Institutions: University of Cambridge, Semantic Technology Institute International, École Polytechnique Fédérale de Lausanne

Language: English

Topic: solar cell performance optimization

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: hybrid

Estimated APC paid: $4,500