NEWS FROM RUSE - THE BLOG
01_COMPANY
01_COMPANY
»
02_SOLAR SILICON
02_SOLAR SILICON
»
03_NEWS+DATES
03_NEWS+DATES
»
04_INVESTOR RELATIONS
04_INVESTOR RELATIONS
»
05_PRESS
05_PRESS
»
Blog 4 Author: John Mott Date: 23 | 04 | 2007
Date: 23 | 04 | 2007
Future Solar Grade Silicon Production Building
X
X
Laboratory
X
X
Arc furnace for Metallurgical Silicon Production
X
X
Office Building
X
X
What is the TDR plant?
In the upper centre of the plant is the building where an arc furnace is currently producing ferrosilicon. Solarvalue will convert the arc furnace to the production of metallurgical silicon. Further refining steps will take place in the future solar grade silicon production building (upper left). The quality of the material will be checked continuously by the on-site laboratory and by equipment located in the production building.
The Solarvalue Facilities at TDR
TDR - Metalurgija is the major part of Tovarna dušika Ruše (TDR,
www.tdr-metalurgija.si), which was one of the first producers of electrochemical products in Europe. Production started in 1918. The main products, which are used in steel production, are calcium carbide, ferrosilicon and similar complex alloys. The plant covers an area of 22 hectares and employs about 300 people.
The last owner of the plant was Holding Slovenske elektrarne (HSE; www.hse.si/en/) a Slovenian utility, who wanted to sell TDR as alloy production was not its core business. The company WP Profil purchased the plant in December 2006. Solarvalue leases the equipment they need for the solar silicon production. WP Profil produces cored-wire products, additives for the steel manufacturing industry, and bought TDR in order to have its own access to the alloys necessary for these additives.
For Solarvalue, the co-operation with WP Profil is of great value. Without this experienced Slovenian insider and Ruse resident Solarvalue would not have access to TDR resources.
www.tdr-metalurgija.si), which was one of the first producers of electrochemical products in Europe. Production started in 1918. The main products, which are used in steel production, are calcium carbide, ferrosilicon and similar complex alloys. The plant covers an area of 22 hectares and employs about 300 people.
The last owner of the plant was Holding Slovenske elektrarne (HSE; www.hse.si/en/) a Slovenian utility, who wanted to sell TDR as alloy production was not its core business. The company WP Profil purchased the plant in December 2006. Solarvalue leases the equipment they need for the solar silicon production. WP Profil produces cored-wire products, additives for the steel manufacturing industry, and bought TDR in order to have its own access to the alloys necessary for these additives.
For Solarvalue, the co-operation with WP Profil is of great value. Without this experienced Slovenian insider and Ruse resident Solarvalue would not have access to TDR resources.
Blog 2 Author: John Mott Date: 18 | 04 | 2007
Date: 18 | 04 | 2007Where is Ruse?
Blog 1 Author: John Mott Date: 03 | 04 | 2007
Date: 03 | 04 | 2007
Solarvalue is setting up its solar grade silicon production in Ruse.
But where is Ruse?
Ruse was part of the Civic Assembly of Communities of Maribor until 1995. Nowadays the municipality (7,293 inhabitants) is independent. With 130,000 inhabitants, Maribor is Slovenia’s second biggest city. Ruse is only 30 kilometers away from the Austrian border and just a 40-minute drive from Graz International Airport. Slovenia is a member of the EU and introduced the Euro in January 2007.
But where is Ruse?
Ruse was part of the Civic Assembly of Communities of Maribor until 1995. Nowadays the municipality (7,293 inhabitants) is independent. With 130,000 inhabitants, Maribor is Slovenia’s second biggest city. Ruse is only 30 kilometers away from the Austrian border and just a 40-minute drive from Graz International Airport. Slovenia is a member of the EU and introduced the Euro in January 2007.
Blog 3 Author: John Mott Date: 18 | 04 | 2007
Date: 18 | 04 | 2007Who is John Mott?
I am the Chief Operating Officer (COO) of Solarvalue Proizvodnja d.d., Maribor, which is a public company and a subsidiary of Solarvalue AG, and which runs the Solar Grade Silicon production in at TDR in Ruse.
I am a senior expert in metallurgical silicon. I did research in Solar Grade Silicon production from metallurgical silicon (mg-Si) at Gaithersburg, Maryland and Martinsburg, West Virginia, USA when I was with Solarex Corporation in the 1980’s. Even at that time we could show that this process could be done. The photovoltaic industry at that time lived on the scraps of the semiconductor industry. As there was a huge surplus nobody bothered to develop a new SGS process but relied on the known sources fed by the Siemens process. But since the Solarex days I have done extensive work in the field of silicon metal and composite materials outside of the photovoltaic regime. When I heard about the Solarvalue project I saw a possibility to realise my near-30-year old vision: plentiful high quality SGS at low cost.
I am a senior expert in metallurgical silicon. I did research in Solar Grade Silicon production from metallurgical silicon (mg-Si) at Gaithersburg, Maryland and Martinsburg, West Virginia, USA when I was with Solarex Corporation in the 1980’s. Even at that time we could show that this process could be done. The photovoltaic industry at that time lived on the scraps of the semiconductor industry. As there was a huge surplus nobody bothered to develop a new SGS process but relied on the known sources fed by the Siemens process. But since the Solarex days I have done extensive work in the field of silicon metal and composite materials outside of the photovoltaic regime. When I heard about the Solarvalue project I saw a possibility to realise my near-30-year old vision: plentiful high quality SGS at low cost.
Blog 7 Author: John Mott Date: 24 | 07 | 2007
Date: 24 | 07 | 2007“What Luck!”
It was really very lucky to be able to lease part of the TDR plant. For a minimum of costs we can take over a fully operating facility with skilled personnel. Imagine how tedious it is to build a completely new greenfield plant: all these time consuming administrative processes – not to mention the time and money for the building and the inventory itself.
TDR is a big asset to Solarvalue as it is a prerequisite to set up 4,400 tons capacity by the end of 2008 for a fraction of the usual costs. Competitors invest at least 200 million Euro to achieve the same capacity as the Ruse plant. Elkem (Norway) will spend 420 million US-Dollars for 5,000 tons capacity by mid-2008. China Southern Glass (China) plans a 150 million US-Dollar investment for 4,000 tons capacity by mid-2008.
TDR is a big asset to Solarvalue as it is a prerequisite to set up 4,400 tons capacity by the end of 2008 for a fraction of the usual costs. Competitors invest at least 200 million Euro to achieve the same capacity as the Ruse plant. Elkem (Norway) will spend 420 million US-Dollars for 5,000 tons capacity by mid-2008. China Southern Glass (China) plans a 150 million US-Dollar investment for 4,000 tons capacity by mid-2008.
Blog 5 Author: John Mott Date: 30 | 04 | 2007
Date: 30 | 04 | 2007The Purity of Silicon
While the chemical properties of silicon make it suitable for these applications, it is its physical properties which make it interesting as a semiconductor, and which have led to silicon being the basic material of most electronic devices and photovoltaic cells. This application had a prominent impact on technological development in the twentieth century and gave Silicon Valley, near San Francisco, its name.
When a semiconductor is very pure it is an electrical insulator; adding just tiny impurities turn it into a conductor. In electronic applications the impurites are called dopants. Depending on the chemical nature of the dopants, silicon becomes n-type or p-type conductive. If n- and p-type silicon are combined, they will show a very unusual behaviour: they will conduct current in one direction, but not in the other. In a transistor, n- and p-layers work as an amplifier or switch.
In solar cells, an additional feature of silicon comes into play: light impinging on the cell generates free positive and negative charges in the silicon, which are collected with the help of the p-n junction and flow as electric current.
When a semiconductor is very pure it is an electrical insulator; adding just tiny impurities turn it into a conductor. In electronic applications the impurites are called dopants. Depending on the chemical nature of the dopants, silicon becomes n-type or p-type conductive. If n- and p-type silicon are combined, they will show a very unusual behaviour: they will conduct current in one direction, but not in the other. In a transistor, n- and p-layers work as an amplifier or switch.
In solar cells, an additional feature of silicon comes into play: light impinging on the cell generates free positive and negative charges in the silicon, which are collected with the help of the p-n junction and flow as electric current.
Ferro-silicon lumps
Silicon (Si) is, after oxygen (O2), the second most abundant chemical element in the earth’s crust and makes up 25.7 % of its mass. However, pure silicon is rare. It most commonly occurs in the form of silica (a combination with oxygen, silicon dioxide, SiO2) and silicate (a combination with minerals and one metal). The best known silica are quartz and sand. Some examples of silicates are feldspar, hornblende, mica, granite and sandstone.
The two most important applications of silicon are silicones and aluminium-silicon alloys. Silicones are used e.g. for technical caulks and oils, silicon alloys are used for the production of cast parts. Silicon is also a constituent of some steels, and is used in the production of cast iron in the form of ferro-silicon or silicon-calcium alloys. The latter are the main products of TDR Metalurgija in Ruse.
The two most important applications of silicon are silicones and aluminium-silicon alloys. Silicones are used e.g. for technical caulks and oils, silicon alloys are used for the production of cast parts. Silicon is also a constituent of some steels, and is used in the production of cast iron in the form of ferro-silicon or silicon-calcium alloys. The latter are the main products of TDR Metalurgija in Ruse.
Blog 6 Author: John Mott Date: 08 | 07 | 2007
Date: 08 | 07 | 2007Silicon – the Second Most Abundant Element on Earth
In nature practically all silicon is “dirty”. It has to be purified. To begin with, silica has to get rid of its oxygen partner through an energy intensive process called reduction, which produces metallurgical grade silicon or mg-Si. Its minimum purity is 98 %.
Solar cells need a minimum silicon purity of ca. 99,9999 %. Material of this purity is referred to as solar grade silicon (SOG-Si or SGS). The higher the purity, the easier it is to attain high solar cell efficiencies.
For microelectronic purposes electronic grade silicon (eg-Si) with 99,9999999 % to 99,9999999999 % purity (10-9 to 10-12) is used, one of the purest man-made materials.
In the beginning of photovoltaics, solar cell manufacturers used the scraps and off-spec material of eg-Si for their production. As demand grew, silicon producers expanded their capacities. In 2006, for the first time, demand from the photovoltaic industry was higher than that from the electronic industry.
Solar cells need a minimum silicon purity of ca. 99,9999 %. Material of this purity is referred to as solar grade silicon (SOG-Si or SGS). The higher the purity, the easier it is to attain high solar cell efficiencies.
For microelectronic purposes electronic grade silicon (eg-Si) with 99,9999999 % to 99,9999999999 % purity (10-9 to 10-12) is used, one of the purest man-made materials.
In the beginning of photovoltaics, solar cell manufacturers used the scraps and off-spec material of eg-Si for their production. As demand grew, silicon producers expanded their capacities. In 2006, for the first time, demand from the photovoltaic industry was higher than that from the electronic industry.
Even “pure” gold, which is 99,99 % pure, is relatively dirty compared to eg-Si or SGS.
Blog 12 Author: John Mott Date: 02 | 10 | 2007
Date: 02 | 10 | 2007Solarvalue purchases production site in Slovenia
“Now we are ‘masters of our own house’ – as I’d say in my mother tongue. After thoroughly evaluating the benefits and risks as well as carrying out a detailed cost-benefit analysis, we decided to grab the opportunity with both hands: the decision was made to buy a large part of the TDR factory in Ruse. The facilities include land, a number of buildings, a large submerged arc furnace and a lot of additional equipment. What I’m particularly pleased with is that we also inherit about 60 TDR employees – people with experience in the operation of arc furnaces - and that we now have all that expertise under one roof.
We still thought a lease would be the ideal solution even as recently as April. Since then, we have recognised that this strategic investment means we will have more planning security and flexibility at our disposal in the implementation of our long-range plans. At the same time we are clearly indicating our long-term commitment to Ruse, where we are going to produce high-quality solar silicon and will be able to gradually extend production. Also, we now have the ideal base to reach our long-term goal – to cover each link in the value-added chain for the solar industry: ingot-casting, wafering, cell production, panel assembly, and design and installation of solar arrays.”
We still thought a lease would be the ideal solution even as recently as April. Since then, we have recognised that this strategic investment means we will have more planning security and flexibility at our disposal in the implementation of our long-range plans. At the same time we are clearly indicating our long-term commitment to Ruse, where we are going to produce high-quality solar silicon and will be able to gradually extend production. Also, we now have the ideal base to reach our long-term goal – to cover each link in the value-added chain for the solar industry: ingot-casting, wafering, cell production, panel assembly, and design and installation of solar arrays.”
Blog 8 Author: John Mott Date: 26 | 07 | 2007
Date: 26 | 07 | 2007The Classic Production Process of High Purity Silicon
The production of high purity silicon is a complicated chemical process. Instead of using solid silicon the classic approach employs gaseous silicon compounds as intermediates. Similarly to the distillation of water, the purification of gases is relatively easy. After purification the compound is converted back to pure silicon.
Trichlorosilane (HSiCl3) is the most commonly used silicon compound, although silicon tetrachloride (SiCl4) and silane (SiH4) are also used. When these gases are blown over silicon at high temperatures, they decompose to high-purity silicon. The process requires a lot of energy and involves large amounts of hazardous materials such as chlorine, or highly inflammable silane.
The most widespread technique is called the Siemens Process. High-purity silicon seed rods are exposed to trichlorosilane at a temperature of 1150 °C. The trichlorosilane gas decomposes and deposits additional silicon onto the rods, enlarging them during the chemical reaction
2 HSiCl3 → Si + 2 HCl + SiCl4.
The resulting product is eg-Si – electronic grade silicon - usable for electronic devices.
Trichlorosilane (HSiCl3) is the most commonly used silicon compound, although silicon tetrachloride (SiCl4) and silane (SiH4) are also used. When these gases are blown over silicon at high temperatures, they decompose to high-purity silicon. The process requires a lot of energy and involves large amounts of hazardous materials such as chlorine, or highly inflammable silane.
The most widespread technique is called the Siemens Process. High-purity silicon seed rods are exposed to trichlorosilane at a temperature of 1150 °C. The trichlorosilane gas decomposes and deposits additional silicon onto the rods, enlarging them during the chemical reaction
2 HSiCl3 → Si + 2 HCl + SiCl4.
The resulting product is eg-Si – electronic grade silicon - usable for electronic devices.
Blog 9 Author: John Mott Date: 26 | 07 | 2007
Date: 26 | 07 | 2007Chemical Alternatives to the Siemens Process
Since the silicon demand for photovoltaic applications has become significant silicon producers have started developing alternatives to the Siemens Process. The objective is to produce SGS - solar grade silicon - while reducing costs and energy input. SGS meets the specifications of solar cell manufacturers but is less pure than eg-Si.
One alternative process uses the Fluidised Bed Reactor, where gaseous silane is blown into the reactor from below, decomposes and is deposited on tiny silicon seed particles. These grow to grains and fall to the bottom as granular solar grade silicon. Compared to the Siemens Process, this process can save about 10% of production costs.
In Vapour to Liquid Deposition (VLD), trichlorosilane is blown from above into a graphite tube at 1.500°C. Liquid silicon from trichlorosilane condenses on the inner walls of the tube and runs to the bottom of the reactor, where it solidifies into granular solar grade silicon.
Another alternative using Zinc Vapor produces ultra-pure silicon by reacting silicon tetrachloride with high-purity zinc vapors at 950°C, according to the chemical equation:
SiCl4 + 2 Zn → Si + 2 ZnCl2.
Finally, silicon powder can be produced by decomposing silane in a Tube Reactor at 800 °C.
One alternative process uses the Fluidised Bed Reactor, where gaseous silane is blown into the reactor from below, decomposes and is deposited on tiny silicon seed particles. These grow to grains and fall to the bottom as granular solar grade silicon. Compared to the Siemens Process, this process can save about 10% of production costs.
In Vapour to Liquid Deposition (VLD), trichlorosilane is blown from above into a graphite tube at 1.500°C. Liquid silicon from trichlorosilane condenses on the inner walls of the tube and runs to the bottom of the reactor, where it solidifies into granular solar grade silicon.
Another alternative using Zinc Vapor produces ultra-pure silicon by reacting silicon tetrachloride with high-purity zinc vapors at 950°C, according to the chemical equation:
SiCl4 + 2 Zn → Si + 2 ZnCl2.
Finally, silicon powder can be produced by decomposing silane in a Tube Reactor at 800 °C.
Blog 10 Author: John Mott Date: 17 | 08 | 2007
Date: 17 | 08 | 2007Solar Grade Silicon from Metallurgical Grade Silicon
In 2006, 4 million tons of metallurgical silicon (mg-Si) were produced, but only around 45.000 tons of expensive, high purity silicon. Since the 1980s, engineers and researchers have been investigating approaches using cheap bulk mg-Si as a raw material to be purified into solar grade silicon (SGS).
Solarex and Siemens (Munich) developed practicable alternatives, but the demand from the photovoltaic industry was so low at the time that it was easier to use the scraps from the semiconductor industry. Following the recent shortage of SGS, old and new manufacturers began researching how to make SGS from mg-Si. Here is a list of manufacturers taken from Photon magazine in February 2007:
Dow Corning (USA, production in Brazil)
Elkem (Norway)
JFE Steel (Japan)
Scheuten/Solarworld (Netherlands)
Southern Glass (China)
Solarvalue AG (Germany, production in Slovenia)
Solarvalue’s approach has two unique advantages: we are already familiar with the process from our involvement in the Solarex activities in the 1980s. And we don’t have to spend a lot of time and money on building new factories.
Solarex and Siemens (Munich) developed practicable alternatives, but the demand from the photovoltaic industry was so low at the time that it was easier to use the scraps from the semiconductor industry. Following the recent shortage of SGS, old and new manufacturers began researching how to make SGS from mg-Si. Here is a list of manufacturers taken from Photon magazine in February 2007:
Dow Corning (USA, production in Brazil)
Elkem (Norway)
JFE Steel (Japan)
Scheuten/Solarworld (Netherlands)
Southern Glass (China)
Solarvalue AG (Germany, production in Slovenia)
Solarvalue’s approach has two unique advantages: we are already familiar with the process from our involvement in the Solarex activities in the 1980s. And we don’t have to spend a lot of time and money on building new factories.
Arc furnaces similar to this one can be used for the production of metallurgical silicon.
Blog 11 Author: John Mott Date: 17 | 08 | 2007
Date: 17 | 08 | 2007Worldwide Silicon Production
Since the boom in photovoltaics began, the silicon market has become very dynamic and most capacity estimates have proven to be too conservative. In the just 5 months between the two studies carried out by Sun & Wind Energy (September 2006) and Photon (February 2007), the estimated production increased by 10 %. The price per kilogram of high purity silicon from Tokuyama Corporation increased by 45 % over three years, to 50 Euro. Spot market prices went up to 150 Euro.
In this booming market, the electronics industry is the only sector with a predictable growth of about 5 % per year. In 2006, 20,000 tons went into this industry, while 24,000 tons where used by the photovoltaic industry. The estimated annual growth rate of photovoltaic silicon is 25 to 30 %, which should lead to a total silicon production of 110,000 tons in 2010, 84,000 tons of which will be for photovoltaic applications. According to some analysts even this high figure will not be enough to keep up with the plans of cell manufacturers. It seems that, for a long time to come, the demand for silicon will be higher than the production capacity.
The main manufacturers in 2006 were:
Hemlock Semiconductor (USA)
Wacker Polysilicon (Germany)
REC Silicon (USA)
Tokuyama (Japan)
MEMC Electronic Materials (USA)
Just as forecasting the figures is difficult, it is also hard to predict who the important producers will be in the coming years. According to statements from the Chinese industry, their contribution to the silicon production of 2010 could be as much as 10,000 tons – a rise from 400 tons in 2006!
In this booming market, the electronics industry is the only sector with a predictable growth of about 5 % per year. In 2006, 20,000 tons went into this industry, while 24,000 tons where used by the photovoltaic industry. The estimated annual growth rate of photovoltaic silicon is 25 to 30 %, which should lead to a total silicon production of 110,000 tons in 2010, 84,000 tons of which will be for photovoltaic applications. According to some analysts even this high figure will not be enough to keep up with the plans of cell manufacturers. It seems that, for a long time to come, the demand for silicon will be higher than the production capacity.
The main manufacturers in 2006 were:
Hemlock Semiconductor (USA)
Wacker Polysilicon (Germany)
REC Silicon (USA)
Tokuyama (Japan)
MEMC Electronic Materials (USA)
Just as forecasting the figures is difficult, it is also hard to predict who the important producers will be in the coming years. According to statements from the Chinese industry, their contribution to the silicon production of 2010 could be as much as 10,000 tons – a rise from 400 tons in 2006!
GERMAN
SLOVENIAN
HOME
IMPRINT