Solar Electricity from Concentrator Photovoltaic Systems
Author(s)
Chan, Ngai Lam Alvin
Type
Thesis
Abstract
This thesis examines the prediction of concentrator photovoltaic system performance,
and a model is presented where estimates are made using basic,
fundamental material and atmospheric parameters, and successfully validated
against measurements from a deployed system, to within 2% accuracy.
A method to characterise the impact of individual atmospheric parameters
on concentrator photovoltaic system performance is detailed and results
are presented for potential deployment locations around the globe, demonstrating
substantial differences in energy yield prediction accuracy if insufficient information is available, with up to 75% relative difference in energy
yield and levelised cost of energy between basic and detailed simulations.
In addition, the competitiveness of concentrator photovoltaic systems in different locations are benchmarked against existing technologies, showing significant geographical variation in their financial viability.
The material quality in single and multijunction solar cells and its effect
on the selection of optimal solar cell designs is investigated and the
radiative efficiency of a device is proposed as a figure of merit to evaluate
material quality. The optimal band gaps are shown to vary substantially
depending on material quality at low solar concentrations, by hundred of
milli-electron-volts, with ramifications for future solar cell designs.
The impact of photon management, through radiative coupling, on cell
performance is quantified for current and future high efficiency multijunction
solar cell structures. Up to 5% enhancement due to radiative coupling
can be expected for quad-junction solar cells, but current designs can expect
below 1% enhancement.
The work covered in this thesis has investigated and highlighted the potential problems associated with not fully understanding the atmospheric
conditions in which concentrator photovoltaic systems operate, providing
evidence and impetus for additional ground measurements or a drastic improvement
in satellite-based measurement of atmospheric conditions. By
integrating atmospheric parameters into an existing concentrator photovoltaic
system modelling tool, new methods to characterise these conditions
has been developed rigorously and accurately simulate system behaviour, a
valuable resource to the field.
In the design of optimal band gaps for multijunction solar cells, the work
in this thesis shows that the material quality must be carefully considered
in any design. A novel method has been developed to quantify material
quality and provide a benchmark of state-of-the-art achieved values. The
role of photon management in the form of radiative coupling is quantified,
through the first examination of enhancement due to the effect, under realistic
atmospheric conditions. This gives cell designers realistic expectations
for performance enhancement.
and a model is presented where estimates are made using basic,
fundamental material and atmospheric parameters, and successfully validated
against measurements from a deployed system, to within 2% accuracy.
A method to characterise the impact of individual atmospheric parameters
on concentrator photovoltaic system performance is detailed and results
are presented for potential deployment locations around the globe, demonstrating
substantial differences in energy yield prediction accuracy if insufficient information is available, with up to 75% relative difference in energy
yield and levelised cost of energy between basic and detailed simulations.
In addition, the competitiveness of concentrator photovoltaic systems in different locations are benchmarked against existing technologies, showing significant geographical variation in their financial viability.
The material quality in single and multijunction solar cells and its effect
on the selection of optimal solar cell designs is investigated and the
radiative efficiency of a device is proposed as a figure of merit to evaluate
material quality. The optimal band gaps are shown to vary substantially
depending on material quality at low solar concentrations, by hundred of
milli-electron-volts, with ramifications for future solar cell designs.
The impact of photon management, through radiative coupling, on cell
performance is quantified for current and future high efficiency multijunction
solar cell structures. Up to 5% enhancement due to radiative coupling
can be expected for quad-junction solar cells, but current designs can expect
below 1% enhancement.
The work covered in this thesis has investigated and highlighted the potential problems associated with not fully understanding the atmospheric
conditions in which concentrator photovoltaic systems operate, providing
evidence and impetus for additional ground measurements or a drastic improvement
in satellite-based measurement of atmospheric conditions. By
integrating atmospheric parameters into an existing concentrator photovoltaic
system modelling tool, new methods to characterise these conditions
has been developed rigorously and accurately simulate system behaviour, a
valuable resource to the field.
In the design of optimal band gaps for multijunction solar cells, the work
in this thesis shows that the material quality must be carefully considered
in any design. A novel method has been developed to quantify material
quality and provide a benchmark of state-of-the-art achieved values. The
role of photon management in the form of radiative coupling is quantified,
through the first examination of enhancement due to the effect, under realistic
atmospheric conditions. This gives cell designers realistic expectations
for performance enhancement.
Version
Open Access
Date Issued
2013-04
Date Awarded
2013-10
Copyright Statement
Attribution NoDerivatives 4.0 International Licence (CC BY-ND)
Advisor
Brindley, Helen
Chaudhuri, Balarko
Ekins-Daukes, Ned
Publisher Department
Physics
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)