Evaluation of the potential of different deposition techniques with regard to reproducibility and robustness for future production of high-efficiency CdTe thin film solar cells.
The main advantage of catalytic combustion is the low thermal nitrogen oxides emission due to the low operating temperature. Many tests have been performed successfully with clean fuels, and a hybrid catalytic and staged combustion technique is also able to burn fuels containing high amounts of nitrogen with low nitrogen oxides emission levels and a combustion efficiency comparable to conventional burners.
In gas turbine applications, a catalytic combustor can lower emissions of nitrogen oxides to less than about 2 parts per million. Catalytic combustion can also burn mixtures whose combustible concentration is below the lean mixture limit of gas phase reactions. This feature leads to an easier control of the rate of production of thermal energy.
Considerable improvements are required before these techniques can be considered for large scale applications including:
reduction of methane losses;
development of cheap and thermostable combustion catalysts;
increasing the temperature stability of the catalysts;
improvement of the fuel preparation and injection systems.
An evaluation has been made of the potential of different deposition techniques with regard to reproducibility and robustness for future production of high efficiency cadmium tellurium thin film solar cells.
The eventual production of a cadmium tellurium thin film solar cell can only be envisaged, if materials and production techniques are cheap enough. This means that the use of the semiconductor material must be made efficient by using thin films and efficient deposition technologies and cheap substrates. Past work and evaluations have shown that this is possible. More of a question arises with respect to deposition technology. Here, a robust process will be required, which leads to a high production efficiency under not too stringent (and thereby expensive) process control. The control bandwidth of all essential parameters for reliable production of high efficiency solar cells should be as wide as possible.
Research so far has resulted in an efficiency of 12% in a cadmium tellurium cadmium selenium CdTe-CdSe heterojunction cell. This process uses cheaper material and is more suitable for mass production and is within the economic limits. Safety aspects can be resolved and the set up of a production plant is under discussion.
The eventual production of a CdTe thin film solar cell can only be envisaged, if materials and production techniques are cheap enough for realization of the final aim of <<1ECU/Wp. This means, that the use of the semiconductor material is made materials' efficient by using thin films and materials' efficient deposition technologies and cheap substrates. Past work and evaluations have shown that this is possible. More of a question arises within the scope of deposition technology. Here, a robust process will be required, which leads to a high production efficiency under not too stringent - and thereby expensive - process control. The control bandwidth of all essential parameters for reliable production of high-efficiency solar cells should be as wide as possible.
This latter technological aspect, besides special development work, such as improving doping and contacting of CdTe, is the central focus of the proposed joint effort. A close cooperation and evaluation of results therefore is essential for the expected success of the work.
In the following the tasks of the individual research groups are listed:
Task 1) COORDINATION AND EVALUATION (Battelle Institut e.V.)
Task 2) CLOSE-SPACED SUBLIMATION (Battelle Institut e.V.) not financed by the EC
Task 3) HIGH VACUUM EVAPORATION AND GALVANIC DEPOSITION (Newcastle- upon-Tyne polytechnic)
Task 4) DOPING AND CONTACTING OF CdTe BY ION-ASSISTED TECHNOLOGY (Istituto Nazionale di Fisica Nucleare)
Task 5) METALORGANIC CHEMICAL VAPOUR DEPOSITION (University of Durham)
Task 6) SCREEN PRINTING OF CdTe (University of Ghent)
Funding SchemeCSC - Cost-sharing contracts
60486 Frankfurt Am Main
DH1 3HP Durham