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In our series on de-globalisation, we shed light on German and European dependencies on raw materials and supply chains.

(Hier finden Sie die deutsche Version des Beitrags [1])

A whopping four times as much solar power as today - that's what the German government wants to achieve by 2030. But where will all the solar cells come from? Probably not from Germany. Yet the local industry was once the world leader. At the beginning of the 2010s, the then black-yellow coalition starved it out with extremely reduced feed-in tariffs. Today, there are only a fifth as many jobs here as in 2011, and the market is now firmly in Chinese hands.

"It is naïve to believe that all you have to do in the West is snap your fingers and cheap goods will come from China forever and ever," says Gunter Erfurt, CEO of the Swiss solar module manufacturer Meyer Burger. "The Chinese solar industry is already extremely busy serving its own market. 50 percent of production will stay in the country this year."

Über Rohstoffe und De-Globalisierung:

The past months have painfully shown that dependence on resources comes at a high price. But can the wheel still be turned back? So let's take a look at the supply situation.

How far Europe could supply itself with strategically important raw materials and what that means for industry is what we want to explore with a raw materials article series.

• New Series: De-Globalisation - How Independent Can Europe Be? [2] [Link auf Beitrag 3601923] [3]
• De-globalisation: Can Europe supply itself with lithium? [4]
• Rare earths and platinum group metals: Can Europe be self-sufficient? [5]
• De-globalisation: Can Europe supply itself with steel and aluminium? [6]
• De-globalisation: Can Europe supply itself with copper? [7]
• Cobalt: Can Europe supply itself with the important raw material? [8]
• De-globalisation: dependence on China remains despite new battery factories [9]

According to his observation, the People's Republic is in the process of buying a "strategic future market". "There is a lot of investment despite much too low margins." In addition, "as a European company producing in Europe, we have to pay customs duties for all components that do not come from the EU due to a lack of suppliers. China, on the other hand, is allowed to import completely without barriers. That is not fair competition.

Solar industry: the supply chains in detail

How can Europe escape this dangerous dependency? The bad news: supply chains are long and complicated - and only as strong as their weakest link. The good news: they already have some pretty strong links.

Let's start with the starting material silicon. It is almost available everywhere as a component of quartz sand, but it has to be processed into polysilicon. Wacker Chemie AG, based in Munich, is one of the market leaders. Together with manufacturers in Norway, enough polysilicon could be produced annually in Europe for 20 to 25 gigawatts of photovoltaic output, estimates expert Jochen Rentsch of the Fraunhofer Institute for Solar Energy Systems (ISE) in Freiburg. That would at least be enough to meet Germany's expansion targets.

In the next step, "ingots" are produced from the polysilicon - blocks or cylinders from which thin wafers are then sawn. Here, Europe is particularly bare. "Ninety-six per cent of the ingots and wafers come from China," says Rentsch. "Even the equipment suppliers for them have disappeared from Europe." The situation is not much better for cell production - that is, the doping and coating of the wafers.

What remains is the assembly of the cells into ready-to-assemble modules. "In Europe, there is a total production capacity of only eight gigawatts per year for this, and it is spread over many small production capacities," says Rentsch. That is not even enough for Germany's expansion plans.

Asian production on European know-how

A particular irony of history: a large part of Asian production is based on European machines and know-how, such as wire saws for cutting up ingots. How could this part of the value chain, of all things, now also disappear from Europe?

"We developed a wire saw in the 2000s that cost a million francs," explains Meyer-Burger boss Erfurt. "Later we were able to sell an improved saw with eight times the capacity for only 400,000 francs. So we made it possible to multiply productivity, but we didn't get paid for it accordingly. So we became victims of our own technological success."

He sees the cause for the decline of local solar manufacturers also, but not only, in political failure. "We equipment suppliers also had our share. We first equipped the German companies and then the Chinese. What came out was always the same solar module as a product. That makes it difficult for competition." Meyer Burger has drawn the consequence from this and no longer sells its equipment to third parties, but uses it exclusively itself to produce cells and modules. In this way, the know-how should no longer flow outside.

New life in "Solar Valley

The result of this strategy can be seen in a symbolic place: the "Solar Valley", an unglamorous industrial area near Bitterfeld-Wolfen. This used to be the heart of the German photovoltaic industry, shaped by the then world market leader Q-Cells. Last year, Meyer Burger moved into the empty 27,000 square metre hall of the solar producer Sovello, which went bankrupt in 2012. Europe's only cell production facility is being built there. It is to become the nucleus of a rebirth of the German solar industry. The first cells are already coming off the production line, and other production lines are being installed alongside.

At the beginning of production are millimetre-thin, fragile silicon wafers. When they arrive, they have already completed a world tour. The raw material polysilicon comes "one hundred percent" from Europe and the USA, emphasises Gunter Erfurt. But to process it into ingots and wafers, it has to go to China. "There is still no other way," Erfurt regrets. To make itself more independent, Meyer Burger recently signed a supply contract with Norwegian Crystals, one of the last two European wafer producers. But that only covers part of the demand.

Process optimisation for wafers

Employees manually insert the wafers into a carrier rack that is reminiscent of a CD stand from the 90s. All other steps are automatic. Whirring conveyor belts and hissing suction pads, shielded by glass boxes, transport the wafers through chemical baths, coating chambers and screen printing machines.

"We have reduced the number of process steps from more than ten to four," says production manager Jochen Fritsche: chemical pre-treatment, passivation, coating with a conductive surface, printing of silver conductive tracks. In the process, the wafers change colour from shiny metallic to silvery matt to the typical shimmering dark blue.

Much of the process optimisation is fine-tuning: for coating, for example, the wafers only lie on a transport frame at the very edge. This means that the top and bottom sides can be treated at the same time. Another work step is saved.

Another improvement: "At no point in the process do the cells get hotter than 300 degrees - and only for a few minutes," says Fritsche. In conventional processes, on the other hand, temperatures of more than 1,000 degrees prevail for several hours. Energy consumption and waste are correspondingly lower, and the heating and cooling phases are correspondingly shorter.

The real secret lies in passivation. It is supposed to reduce charge carrier losses on the surface. In "heterojunction" cells, a thin layer of amorphous silicon is applied on both sides. This should not only increase voltage and current, but also the conversion of diffuse light. In addition, the modules are bifacial, i.e. they can use light from both sides. According to Meyer Burger, the result is an efficiency of up to 25 percent at cell level, about a quarter more than conventional silicon back-contact cells. The heterojunction cells are also said to be more durable and less temperature-sensitive. Meyer Burger offers a 30-year warranty on glass-backed modules.

Employees from the past are coming back

People only have to lend a hand again to pack the finished cells for onward transport to Freiberg in Saxony. There they are assembled into modules - also in a reactivated solar factory. It belonged to the defunct Solarworld group, stood idle for years, but was still equipped with well-maintained Meyer Burger machines. Many of the employees had also worked in the solar industry during the first wave - and have now "come back with great enthusiasm", says Fritsche.

In the first construction phase, Meyer Burger plans to produce cells with a total capacity of 400 megawatts per year in Solar Valley. By 2023, this figure is expected to reach 1.2 gigawatts. This corresponds to almost a quarter of the total German capacity added in 2021 - a big step compared to the status quo, but it will probably not be possible without imports in the future.

The construction of another gigawatt cell factory is planned for 2024, ideally also in Solar Valley. "For cell production, you need a certain density of technological know-how," says production manager Fritsche. For this reason, he says, cell production should remain concentrated at one location. "The module factories, on the other hand, will be set up decentrally, close to the corresponding markets" - if only because of the higher transport costs of the voluminous modules. Meyer Burger's second module factory is currently being built in Arizona.

Sustainable upswing or flash in the pan?

So something is happening with cells and modules. But what about wafer production? This is where the Freiburg-based start-up NexWafe, a spin-off of Fraunhofer ISE, comes in. It wants to process silicon directly into wafers instead of first melting it, letting it solidify and sawing it. To do this, it is vaporised and then deposited as a wafer-thin layer on a reusable seed wafer. This not only eliminates the need for wire sawing, but also reduces material consumption. According to NexWafe, the process generates 30 per cent less costs and 70 per cent less CO2 emissions than conventional wafer production.

If the announcements prove to be true in practice, the process has the potential to "replace classic wafer production over time", according to the trade magazine Photon. So far, however, there is only one pilot line in Freiburg. Series production has been postponed again and again. Now it is to begin in 2024. The planned location is - surprise! - the Solar Valley.

Solar industry: What the future holds

"It is important to have a secure market perspective," says Fraunhofer researcher Rentsch. In view of the ambitious expansion targets, the situation today is therefore quite different from ten years ago. "Back then, growth was only possible with the right incentives. Today, the production costs are so low that it pays for itself. That's why there's good hope that the industry won't suddenly collapse again." In any case, European production is competitive: "In the past, it was always said that labour costs were lower in Asia. But that argument no longer holds water today because production is highly automated. And then there are the rising transport costs.

And what about the skilled workers? Rentsch is not too worried about the production of cells and modules: "The specialists for factory automation are not so specialised that they could not come from other industries" - for example if suppliers for combustion engines have to change their portfolios because of increasing electrification.

When it comes to installing the finished modules, however, the situation is somewhat different, says Rentsch: "You do wonder how that's supposed to happen. On the other hand, there were already enough craftsmen ten years ago to install seven gigawatts per year. "Every roofer back then was also a solar installer. That should come back."

So there is much to suggest that the European solar industry is regaining its former strength - especially the huge demand. But this is not a foregone conclusion in view of the entangled international supply and competitive relationships.

There are enough political instruments to nurture the tender seedlings: with the Important Projects of Common European Interest and the European Chips Act, the EU is channelling billions into hydrogen and battery cell research and into building up its own chip industry. Representatives of the solar industry would like to see something like this for their sector. According to Gunter Erfurt, the money would be well spent: "For a production capacity of 30 gigawatts per year, you would have to invest about 10 to 12 billion euros Europe-wide, right across the value chain. That is about half the annual cost of importing fossil energy from Russia."

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(jle [11])

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[1] https://www.heise.de/hintergrund/De-Globalisierung-Wie-die-Zeichen-fuer-eine-europaeische-Solarindustrie-stehen-7279541.html
[2] https://www.heise.de/hintergrund/New-Series-De-Globalisation-How-Independent-Can-Europe-Be-7254623.html
[3] https://www.heise.de/hintergrund/Neue-Serie-De-Globalisierung-Wie-unabhaengig-kann-Europa-sein-7251008.html
[4] https://www.heise.de/hintergrund/De-globalisation-Can-Europe-supply-itself-with-lithium-7259141.html
[5] https://www.heise.de/hintergrund/Rare-earths-and-platinum-group-metals-Can-Europe-be-self-sufficient-7269833.html
[6] https://www.heise.de/hintergrund/De-globalisation-Can-Europe-supply-itself-with-steel-and-aluminium-7269897.html
[7] https://www.heise.de/hintergrund/De-globalisation-Can-Europe-supply-itself-with-copper-7269498.html
[8] https://www.heise.de/hintergrund/Cobalt-Can-Europe-supply-itself-with-the-important-raw-material-7273506.html
[9] https://www.heise.de/hintergrund/De-globalisation-dependence-on-China-remains-despite-new-battery-factories-7276881.html
[10] https://www.instagram.com/technologyreview_de/
[11] mailto:jle@heise.de

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