From zero to Giga in 12 years: the exemplary story of 3Sun, our solar panel factory

A word from Francesco Starace


Sometimes the speed of certain technological developments can be hard to believe: it can seem as if history has suddenly been put on fast-forward. And you can sense how quickly situations can evolve if you point in the right direction.

One example for us was the growth path of our 3Sun photovoltaic panel factory in the so-called “Etna Valley,” Sicily’s industrial and technological hub. On April 1st, 2022, less than 12 years after its creation, the factory made another important leap forward, obtaining European funds for innovation. Thanks to an investment of around 600 million euros, of which almost 118 million have been earmarked from the European Fund for Innovation for large-scale projects, 3SUN is set to become a “Gigafactory,” with the development of the TANGO (iTaliAN pv Giga factOry) project. It will produce a total of 3 GW of panels each year, a 15-fold increase with respect to its current output, thus making it Europe’s largest production facility for high-performance bifacial photovoltaic panels.

Global demand for solar photovoltaic modules is growing at an ever-greater pace and Europe alone will absorb a large part of the extra demand, thanks to the substantial competitiveness and cost effectiveness of this technology. The new investment will enable us to reach 3000 MW of productive capacity a year in Europe and will mark an important leap forward for Italy in underlining our technological leadership in the sector.

The 3 GW of photovoltaic panels produced every year by the Gigafactory will be able to generate up to approximately 5.5 TWh of electricity annually from renewable sources and, from a sustainability perspective, avoid the equivalent of almost 25 million tons of CO2 in the first ten years of operations. By the same token, the production generated by the panels from the Gigafactory has the potential to avoid the purchase of almost 1.2 billion cubic meters of gas each year, reducing energy dependence on fossil fuels by replacing them with national production of renewable energy.

This success story is even more significant when we consider that, at the time of 3Sun’s foundation, this was a new area for Enel. Until then we had always produced a good that is almost intangible – energy, but now we were now making something solid – photovoltaic panels. It is, nonetheless, an enterprise of great value to us: creating an internal production chain and reducing dependence on foreign resources, boosting technological innovation to achieve ever better efficiency levels. All this is with the aim of promoting a growing roll-out of solar energy, while helping to regionalize the value chain in Europe.

Finally, another aspect worth highlighting is employment. In Catania 3Sun has played a driving role in the local technology hub, also in terms of employment. It has been estimated that the Gigafactory will create around 1,000 jobs (both directly and indirectly) in the area by 2024.


The various stages in a success story

The 3Sun adventure began in Catania on August 1st, 2010. By the end of 2011 the factory was already set to begin industrial production and since then it has gone from strength to strength: after just one year it passed the symbolic milestone of one million panels produced and in 2017 that total reached 6.8 million.

At this point a new story began: we decided to take a chance on the technologies of the future. In the case of solar panels this meant passing from thin-film silicon modules, which at that time were considered mainstream, to bifacial modules, a more innovative type of technology that’s capable of using both direct light and reflected light absorbed on the back of the panel.

The bifacial panels are more robust and have a longer duration of up to 30 years. But their main benefit is that they produce more energy in relation to surface area used, thanks to their greater overall efficiency.

Our factory soon became a trailblazer and other producers followed our example: this was a sure sign that we were moving in the right direction. Meanwhile, we were already thinking about the next step: hetero-junction (HJT) modules that were even more efficient. This technology is so efficient, in fact, that at the beginning of 2020 our cells achieved a yield of 24.63%, a world record.

When it comes to further increasing efficiency, today the new frontier is the Tandem cell. As the name suggests, it consists of two cells, one of which is our industrial HJT silicon cell, onto which another cell made of perovskite is grafted. This is yet another example of how materials science is making it possible to create new solutions for the growth of renewable sources.


Open Innovation and sustainability

Nor were we alone in this journey. We immediately adopted what we call the Open Innovation approach, welcoming good innovative ideas both from within and outside the organization. Initially, we were “the new kid on the block,” having just entered the market, and so we turned to the experts in the sector, the Japanese company Sharp, with whom we set up a joint venture.

Soon we learnt to stand on our own two feet but we chose to continue building partnerships in order to keep innovating. The efficiency record was made possible thanks to a procedure developed together with France’s Institut National de l’Énergie Solaire, while for the Tandem cells we are working with Italian research centers and firms: ENEA, the CHOSE Center at the Tor Vergata University in Rome, the Institute of Structure of Matter at the CNR (National Research Council) and the BeDimensional company, a spin-off of Graphene Labs, which is part of the Italian Institute of Technology in Genoa.

3Sun is on its way to becoming Europe’s largest producer of PV panels, and for some years it has been a flagship in terms of innovation technology and automation of industrial processes. Work is being carried out on the development of new technologies that can enable the use of new, recovered materials, such as recycled plastic. 3Sun was also the first factory of this type in the world to attempt to recycle materials used in production processes, such as silver, glass, resins and indium. This is a circular economy model that makes it even more environmentally sustainable, which is a core value for the Enel Group and a natural vocation for a plant that produces solar panels.