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Projects: Projects for Investigator
Reference Number GR/T03314/01
Title Optimised Efficiency of Thin Film Photovoltaic Device
Status Completed
Energy Categories Renewable Energy Sources(Solar Energy, Photovoltaics) 100%;
Research Types Basic and strategic applied research 100%
Science and Technology Fields ENGINEERING AND TECHNOLOGY (Electrical and Electronic Engineering) 100%
UKERC Cross Cutting Characterisation Not Cross-cutting 100%
Principal Investigator Dr R Gottschalg
No email address given
Electronic and Electrical Engineering
Loughborough University
Award Type Standard
Funding Source EPSRC
Start Date 01 January 2005
End Date 31 December 2007
Duration 36 months
Total Grant Value £208,710
Industrial Sectors Energy
Region East Midlands
Programme Materials, Mechanical and Medical Eng
Investigators Principal Investigator Dr R Gottschalg , Electronic and Electrical Engineering, Loughborough University (100.000%)
Web Site
Abstract A major obstacle when producing high efficiency, integrally connected thin film solar cells is the inhomogeneity in the deposition. For example, if one small area on one cell of a 1 m x 1 m module (with typically around 70-100 cells integrally connected cells) causes this cell to perform 10% worse than the other cells, the whole module will perform 10% worse, i.e. a small inhomogeneity affecting about 1 % of the area can result in 10% efficiency losses.The aim of this project is to work to develop methods to investigate these inhomogeneities and increase the understanding and the quantification of such spatial inhomogeneities. Particularly problematic are the new, high-efficiency multi-junction cells, i.e. devices where two or more cells are stacked on top of each other which are integrally connected. Measurements of spatial properties will typically be affected by both cells or by the less well produced one within the stack. The project will develop a measurement system capable of mapping the spatial production quality for each junction separately. Secondly, the project will develop the science behind the measurement system to make it a useful tool for the investigation of production quality.Few techniques exist to map production quality. One of them, Laser-Beam-Induced-Current (LBIC) mapping has the potential to be a non-destructive technique for multi-junction devices. Applying appropriate bias illumination and using a carefully chosen laser will allow to exite each junction separately. The approach is similar to the measurement of the spectral response of multi-junction devices. It was shown that it is possible to measure integrally interconnected modules by other groups, but the investigation of multi-junction devices is realised nowhere in the world.A system capable of measuring single-junction cells of a size up to 1.2m x1.2m is currently commissioned at CREST. This grant will enable the extension of this system to multi-junctions. Ina second stage, the system will be extended to measure spatially resolved I-V characteristics. The science required in identifying a range of production problems will be developed Vs part of this proposal. Samples needed for this undertaking will be delivered by the industrial collaborators
Publications (none)
Final Report (none)
Added to Database 01/01/07