“We are currently in a decisive phase for photovoltaics”
Rutger Schlatmann heads the Competence Centre Photovoltaics Berlin at HZB and teaches as a professor at HTW Berlin University of Applied Sciences. Since October 2022, he has been the Chair of the European Technology and Innovation Platform for Photovoltaics (ETIP PV). © HZB/Michael Setzpfandt
The expansion of photovoltaics is progressing. Nevertheless, the increase must be fast.
By 2030 15.6 GWs of solar power should be generated, otherwise, there is a risk of an electricity shortfall. © Solarwirtschaft.de
The HZB researcher Rutger Schlatmann has been elected as the new Chair of the platform ETIP-PV, which brings together representatives of science, industry and politics from all over Europe. We interviewed him about the current boom – and about why the photovoltaics ship has not yet sailed for the EU.
Rutger Schlatmann, when you specialised in photovoltaics some decades ago, it was a niche topic. Did you already have an inkling back then, that it would ever come to the boom we are experiencing today?
Rutger Schlatmann (With a laugh): I wish I had such clairvoyant abilities! There were some indications: for example, photovoltaics had grown continuously over the previous 20 years, and it was becoming increasingly clear how important it is to avert the climate crisis. So, I was confident that the market would gain momentum in Europe. But that it would come to two such deep ruptures as the coronavirus pandemic and the war in Ukraine – I did not see those coming.
What do these crises have to do with photovoltaics – except of course for the increased demand for new energy sources?
We have long glorified globalisation. Now, all of a sudden, we recognise that we, in Europe, can’t even produce as simple an item as a face mask without relying on a supply chain that extends all the way back into the Far East. And of course, that applies even more to complex products such as medicines, semiconductor chips and, indeed, solar cells.
That would be the geostrategic perspective. What is the technological outlook on photovoltaics today?
Back when I got into research, practically nobody took the field seriously. But, for a number of years now, solar electricity has had the lowest production costs – it is more economical than electricity from oil or gas and, as probably goes without saying, it’s much cheaper than nuclear energy. And that is despite the fact that there’s still enormous potential for advancements in the technology. We are currently in a decisive phase for photovoltaics, and the good news is: the research landscape in Europe, and in Germany especially, has become much stronger and larger than one might have expected given the industrial capacities that still exist in this field here in Germany.
But we’re seeing strong output from photovoltaics researchers in China as well, aren’t we?
Most definitely, and we should not underestimate that in terms of quantity or quality. But we’re in the lead for certain technologies that are currently in very high demand because Germany has been investing a lot of research funding into them over the past ten years. Perovskite tandem solar cells are a good example: these have two overlaid layers, a silicon layer and a perovskite layer, each which converts different colour components of sunlight into energy, and that makes them work at much higher efficiency than conventional solar cells. There’s been incredible progress in their efficiency, but also in their stability. At HZB alone, we have recruited several groups and talents dedicated to this technology. And it’s like that not only in research, by the way, but also in the commercial sector.
That brings me to the next question. A few weeks ago, you entered office as the Chair of the European Technology and Innovation Platform for Photovoltaics. What new things have you learned since then?
More than anything, I have gained deeper insights into the regulatory and political conditions. An awful lot has started moving in this field. The dominant topic is of course the Inflation Reduction Act of the US, a humungous programme aimed at supporting the establishment of production capacities. The investment opportunities are so attractive that, when talking with companies these days, I keep hearing that they would actually like to invest in Europe, but that the differences are so great that they’re in fact better off producing in the US and then shipping the goods to Europe from there.
Couldn’t we, in Europe, just skip the traditional silicon solar cell phase and go straight on to scaling up production of tandem technology?
No, there are two reasons why that won’t work. The first is that the ship has not yet sailed for silicon cells; quite the opposite. And, secondly, we first have to build the entire value creation chain in Europe back up from scratch – and for silicon technology that would be okay. The solar companies need extremely transparent glass, for example. Companies that can produce such a thing do exist in Europe, but they shut this segment down a long time ago because there was no demand. And the same goes for so many other components you need to manufacture PV modules. Luckily, the knowhow for all those things still exists – but production has to be ramped up again first.
So, are the necessary steps actually being taken towards this?
It never ceases to amaze me how politics works in the EU – how some countries can block a sensible bill, for example, just so that they can get more for themselves out of the negotiations. Although, I can imagine that the European Commission, as well as the national governments, are well aware of how great the pressure to act is. Yet there are also rays of hope: in battery production, for example, an investment climate has set in that has made Europe attractive again for an industry that had in fact long since migrated away.
Would you say you are more optimistic or more pessimistic about the PV industry, now that you have had several chances to look behind the scenes from your new office?
Without a doubt: I am more optimistic.
This interview was published in the HZB magazine lichtblick.
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