From pv magazine 10/2022

Coming next month, a special collaboration between pv magazine and Enel that takes a look at the Italian energy giant’s move into solar manufacturing down in Sicily and continued focus on renewable energy projects the world over.

The 3Sun factory in Catania, Sicily already has a history of moving with the times. It first opened back in 2011, as a partnership between European semiconductor manufacturer STM, Japanese electronics giant Sharp, and current owner Enel Green Power (EGP). The latter took over the shares of the other partners in 2014, taking full control of the 3Sun joint venture that operated the factory.

Originally, 3Sun produced amorphous silicon thin-film modules at the site. This technology could only reach 8% to 12% efficiency – even today its record lab efficiency stands at 14%. However, its reduced silicon consumption made it an attractive option for some manufacturers in the early part of the last decade. When polysilicon fell from around $60/kg in 2010 to less than $20/kg in 2013, amorphous silicon quickly became uncompetitive with crystalline silicon cells.

In 2017 EGP announced plans to invest €80 million ($78.9 million) in converting the factory to produce 200 MW per year of silicon heterojunction (HJT) modules, placing it among the earliest in a wave of new investment in this technology. The first modules rolled off this production line in the second half of 2019, and since then EGP has announced further plans for an additional €600 million investment to scale the factory’s cell and module capacity from 200 MW to 3 GW by the middle of 2024, making it the largest PV cell/module manufacturing project in Europe.

This upgrade, which EGP is calling the Tango project, an almost acronym for Italian PV gigafactory, will deploy many of the latest technologies in PV manufacturing: HJT cell technology in combination with newer, less established techniques for cell interconnection, module lamination and other processes. Later, the project will also be looking to implement perovskite tandem cell technology, a promising new route to higher performance that has seen little commercialization so far.

This comes at a time when solar manufacturing is moving into new regions worldwide, and Europe is keen to meet at least a significant chunk of its demand for solar energy without having to rely on other parts of the world for supply. With this in mind, EGP was able to receive €118 million toward the factory from the European Union’s Innovation Fund. The Innovation Fund will distribute around €38 billion (depending on carbon price), taken from the revenues of the EU emissions trading scheme, and focuses on “highly innovative technologies and big flagship projects within Europe that can bring on significant emission reductions,” according to the fund’s website.

That EGP was able to secure this funding for the project is a clear demonstration of its leadership in terms of working with many of the latest and most innovative technologies in solar manufacturing. This round of funding was open to projects across renewable energy, energy storage and energy intensive industries. The European Commission evaluates projects on innovation, project maturity, scalability, cost efficiency and potential for emissions avoidance. Projects are analyzed in detail by independent experts from the relevant field. “The competition was really, really tough, and for Tango it is really a big success,” Maria Velkova, deputy head of unit for low carbon solutions at the commission’s Directorate-General for Climate Action, told pv magazine. “In the first call, which was for €1 billion, more than 300 projects applied, 70 were selected for a second phase and we were able to offer funding to seven projects.”

With the EU now placing higher importance on domestic manufacturing, the EU Innovation fund’s next call for large scale projects, which is set to be published in November and make up to €3 billion in funding available, will have a dedicated category and include a certain amount set aside for manufacturing projects. “In the first two calls it was completely open, just the best projects on the five criteria,” said Velkova. “Now we will make the priorities more clear, and it is so important to support manufacturing in the EU.”

European technology

One notable aspect of the Tango project is that many of the technologies set to be deployed in the factory are being supplied by European equipment manufacturers, for whom the project is something of a lifeline after several years with little demand, especially from projects happening locally. Earlier this year, German company 3D-Micromac confirmed that it would supply its cell cutting tool to the project. “3D-Micromac’s microCELL systems are proven in heterojunction solar module and cell manufacturing, and all of our experience from these past installations will be fully utilized to support this major expansion project,” stated the company’s CEO Uwe Wagner, announcing the partnership. “As the Enel Tango project shows, the future of the PV industry in Europe is very bright, and 3D-Micromac looks forward to being a strong partner in supporting the growth of the PV market in Europe, as well as around the globe.”

A trend of deploying newer technologies, and those that offer plenty of flexibility in terms of cell type (and size) that they can process, is evident in much of the equipment chosen. The factory will also deploy multi stack laminators supplied by Germany’s Robert Bürkle GmbH – which add higher throughput compared to standard single stack machines, and can also process various module dimensions. And EGP will also utilize cell interconnection based on an electrically conductive adhesive, supplied by another European company. This is a less tested approach, with most manufacturing still using soldered cell interconnection – though one that will have a significant opportunity to gain share in the coming years, as HJT cells are too sensitive for the high temperatures most soldering processes would expose them to. 3D-Micromac also confirmed that the flexibility of its tools was key to it being chosen. “One of the big advantages that we had is the flexibility of our tool, that we are flexible in both the initial cell size and the cutting pattern,” said Thomas Kießling, senior product expert at 3D-Micromac. “That was one of the reasons why we were chosen for this project.”

Manufacturing incentives

The level of innovation in the Tango fab, along with the decision to work with European technology suppliers, was also key to the commission’s funding decision, and will now require the project to continue along these lines. “One condition is that they have to deliver what they promised,” said Velkova. “They need to deliver it with the specific technology they have explained. If they find some problem and decide they want to do something less innovative, that would likely be considered a substantial change to the project and could affect the funding.”

Velkova notes that in terms of capacity as well, EGP must deliver a minimum of 75% of the 3 GW promised in the project’s outline to receive the full funding, and that so far it appears well on track to meet all of these milestones.

Others in the solar industry are pleased to see incentives on the table for solar manufacturing in Europe, “I think it’s strategically wise to move directly to the latest technologies with the highest efficiencies,” said Johan Lindahl, secretary general of the European Solar Manufacturing Council (ESMC). “This is one opportunity that Europe has, if you compare to Asia where they have made huge investments in earlier technologies and want to pay off these factories before they take the next step.”

The ESMC is also calling for strong ecodesign legislation and mandatory reporting of emissions footprints from manufacturing, noting that though buyers in Europe appear willing to pay a premium for “low carbon” modules, legislation is needed to ensure fair competition with producers in regions that may not be held to the same standards.

Challenges to come

Lindahl notes the importance of funding like that made available to EGP to ensuring the success of this high technology approach. “Taking advantage of these latest technologies produces a bit more uncertainty, simply because they are new,” he said. “So public support for innovation is highly welcome.”

While EGP’s experience operating its 200 MW production since 2019, along with its list of veteran technology providers, will assist in achieving module production. Yet plenty more challenges will appear, including from European competition as the region scales up. “Just a few gigawatts is not enough,” said Lindahl. “If you look at the targets in the RePower EU strategy, we need to be installing something like 60 GW per year in Europe, so we need to be producing similar amounts to that here.”

Heterojunction technology comes with considerably higher consumption of silver than today’s PERC technology or some other high efficiency options, and its use of indium may also provide challenges in the future. “If HJT gains significant market share and the overall market grows significantly, as we expect, you’ll quickly start using a lot of indium, which is liable to push up prices” said Alex Barrows, research director at technology consultants Exawatt. “And if that doesn’t happen, it likely means other high efficiency technologies have performed well, which could put you in a challenging position as an HJT manufacturer.”

EGP and others are certainly hard at work on solutions to these and other challenges. The plan to integrate perovskite tandem cell manufacturing, an even newer technology never produced at anything close to gigawatt scale, presents another significant uncertainty, although one that could result in a big jump forward in terms of cell efficiency.

In the meantime, the Tango project represents a flagship for PV manufacturing in Europe, and its success could carve out a space for much more. “We have Tango and a few other projects moving forward that will hopefully serve as a catalyst for the whole European PV value chain,” said Lindahl. “These first projects are especially important because if they aren’t successful, the will to invest in others might be significantly reduced.”