It is astonishing the level of innovation we have seen in PV, says Stassen, only a few years ago we had cell lines being sold with 16% or 16.5% efficiencies and these same lines are now turning out 17.5% cells.
Stassen was speaking to pv magazine in the wake of the first Future PV Forum, held in Berlin. Heraeus was co-organizer and one of the Forum sponsors. Andreas Liebheit headed up the advisory board.
The Forum brought together a range of technologists, from startups through to established companies such as Heraeus, to showcase efficiency boosting and cost cutting technologies that are close to or at the point of commercial application. In reflecting on the presentations and conversations held at the event and in its aftermath, Stassen notes that small changes, rather than step changes, are the likely technological pathway the PV manufacturing industry will take.
I dont see any major breakthroughs impacting on the industry and creating sudden improvements, says Stassen. I see an overall improvement of the entire field with evolutionary steps.
At present leading the charge in terms of technological improvements in commercial production is PERC applications. Stassen said that this was because it requires relatively minor changes to production processes without radically changing lines.
While Stassen notes that a clear technological roadmap for solar manufacturing is still lacking and past roadmaps have frequently been wrong crystalline silicon (c-Si) manufacturing will remain the predominant technology. Within this, however, he sees a number of different directions that the industry will take within c-Si.
I see all sorts of new things within c-Si. That be multijunction using amorphous silicon or tandem cells with perovskite, says Stassen. It might be another add-on like we are investigating like replacing the PERC backside with a polymer material, but at this moment there are many possibilities for the future.
Essentially, the Heraeus technologist argues, a focus on increases in conversion efficiency is absolutely key for solar to continue to develop and for the industry to grow.
We are still a young industry and we are still not where we have to be, he says. We have to go for higher efficiencies and that is through a focus on innovation and technology.
In the coming weeks pv magazine will be presenting the technologies that were featured at the Future PV Forum and speaking with the technologists driving the new approaches into commercial application.