A.
OBJECTIVES ( Sahara 'a priori' project aims)
Main
fundamental objectives were :
A.1
At technical level, to review state of the art of
current industrial and R&D activities on Solar
Grade Silicon production to ascertain if one or more technologies exist
mature for industrial production or for pilot phase and a complete definition of
the same technologies
A.2.
At economic and commercial level, to update and validate [ALTN 2] study
previously carried out by BAYER and LIFE within EPIA in 1999 to ascertain if a
shortage of feedstock is confirmed and therefore if the need of a SoG-Si
production still remains
A.3
In case of positive answers for points A.1 and A.2 above, to promote some
kind of association actions (Joint-ventures, Consortia, Link-agreements etc.)
among mainly European partners for the R&D development first, the industrial
development later and the commercial phase to immediately follow for those
viable SoG-Si production routes.
A.4
At policy level, to understand what role can Public Organizations play (National
Governments, European Union, etc.) and which policy could be suggested, to
sustain the risk and the huge investments of the actions described in A.3 above.
B.
RESULTS ( Sahara 'A
posteriori' projects results )
B.1
Six projects
were considered for further development.
These projects are:
1. The Wacker Chemie project with FBR development
2. The Tokuyama project with a new type of deposition reactor
3. The ASiMI/REC project with FBR development.
4. The Degussa/SolarWorld project with tube deposition
5. The SOLSILC/SPURT project with direct reduction and a melt purification cycle
6. The ELKEM project based on purification of metallurgical grade silicon
In particular those directly or indirectly promoted by SAHARA are:
3.
The ASiMI/REC
project, which
is “ready to go” into industrial production with their relaxed Siemens
process in 2003 , whereas the ASiMI/REC FBR project
still has to go
through the pilot phase.
4. The Degussa/SolarWorld project, which is considered as the most ambitious project (high end technology from the world biggest producer of Chlorosilane with high end product at a price target in the range of 20 €/kg along the guidelines set forth by the “Feedstock Bottlenecks Analysis” Study), which needs a pilot phase prior to industrialisation.
5. The SOLSILC/SPURT project, which is already now conducted by a European consortium made of research institutions and industrial companies. This process is presently operated partly at pilot scale, partly at lab scale, and the whole process is planned for pilot phase in 2004 having as a goal a product at a price below 20 €/kg.
A “ranking” of these different technologies is not possible at the current state of development. All projects should go through the state of pilot production or industrial production; as appropriate, to allow a more detailed judgment.
Projects 3 and 4 use, indeed, a very similar technology for the production of silane, and only the foreseen deposition techniques are different. Project 5 is completely different and it is an alternative to the gas phase processes.
The SPURT consortium will deliver a different product of probably lower grade and lower price than the gas phase technologies, and they will probably address at least partly another market segment than the other producers.
B.2 The [ALTN2] study was perfectly
validated in its fundamental statements.
B.3 Of the six projects above Sahara
certainly gave its strong contribution in promoting the Degussa/SolarWorld Joint
Venture, the ASiMI/REC Joint Venture and the SPURT Consortium, by means of,
among others, several meetings, two European Round Tables and a European
Workshop. In view of the fast moving sector, LIFE, who will continue working on
this project - in particular on the setting up of an EU - warranted Rotational
Fund (EU-WRF) described below - partly with its own funds and partly co-funded
by the Calabria Region Government, has already scheduled a follow up workshop
besides the Sahara project scope in
the South of Italy later this year
B.4 As it clearly appears from above
statements in Europe four are the routes which with equal interest converge to
the same objective. In particular two: Wacker Chemie and ASiMI/REC, are already
at the industrial stage level with their relaxed Siemens process with Wacker
Chemie already producing at 27
€/kg and ASiMI/REC to start production in 2003.
Both Wacker Chemie and
ASiMI/REC FBR projects still
have to go through pilot phase. SPURT is scheduled for the pilot phase in 2004.
Above projects pilot phases are certainly recommended together with the
Degussa/SolarWorld project ready for the pilot phase now. This last one
involves an high end technology and
consequently produce an high
quality feedstock, possibly with an
higher risk than the others but at
a lower price confirming , as stated above, the [ALTN2] estimates which
foresaw a price below 20
€/kg.