Perovskite: Hype or solar disruptor?

Some topics are just too sensitive for polite company. Take for example the 2016 US presidential election, British versus American humour - or is it humor?, and, of course, perovskite.

For the latter, this may change.

Perovskite is set to disrupt global solar markets by vastly both reducing the cost of solar cells and increasing their efficiency. Today’s silicon-based solar will look antiquated; traditional solar vendors will fold.

Or, they won’t and it isn’t. It all depends on with whom you speak. And when.

Since 2009 when research began on this synthetic crystalline material for solar purposes, scientists have been unable to counter the material’s instability. Namely, perovskite disintegrates once outside (which is where you want solar panels.)

Local Debates

The material was a hot topic of debate at The Solar Agenda 2016 at the collocated Middle East Electricity and Solar Middle East events.

“Silicon would probably still dominate the market for quite a long period of time,” said Dr. Marc Vermeersch, Managing Director, Solar and Photovoltaic Energy Research Center (SPERC), King Abdullah University of Science and Technology (KAUST). He spoke on the innovation panel.

Vermeersch said that at SPERC, “We do a lot of perovskite. We do a lot of organic hybrid printed PV. Ninety percent of the Solar Research Centre (SPERC) activity - 3,000 square meters of clean rooms - are dedicated to emerging technologies. But we believe these emerging technologies will take some time because they are today not bankable.”

Added panelist Claudio Palmieri, CEO of CLS Energy Consultants, “For any new technology coming in the market where you have existing technologies that have a market penetration of 90%, it is an uphill battle… We all know the limitation of crystal and solar - 39% maximum (solar efficiency). So I think the next 10 years, I hope we would see a bit of change, but I don’t expect it (soon).”

Vermeersh concurred.

“There are still a lot of things to be done in silicon, and more globally in mature technologies … (Also,) manufacturers will most probably accept emerging technologies that would complement the existing mature technologies. In the short time frame - 10 years, they will probably not accept to switch to something new. Probably not, unless there is a big disruptive technology.”

Enter Wannabe Disruptors

Advancements have come monthly since summer, culminating in two US-based research groups claiming breakthroughs that could finally make perovskite commercially viable.

This month, a team at University of California, Berkeley, claims to have solved perovskite’s degradation troubles by sandwiching two types of the material, all coated in an aerogel of graphene. The resultant solar cells reportedly peak at 26% conversion efficiency – several points higher than silicon cells - and the ability to draw energy from even invisible infrared light.

Meanwhile, the US Energy Department’s National Renewable Energy Lab (NREL) has proposed solar cells made of thin films of quantum dots of the material, as well as new manufacturing methods, since the uniform creation of reliable perovskite solar cells has been a challenge.  

Dubai’s Curtain Wall Windows

The promise is there, said Dr. Varun Sivaram, Douglas Dillon Fellow, Council on Foreign Relations (CFR), another panelist at The Solar Agenda 2016.

“I know you folks in Dubai really like your floor to ceiling glass windows in your buildings. One day those floor to ceiling glass windows could be covered with a solar film of perovskite. That kills two birds with one stone. One bird is, it reduces the heat intake from the light that strikes the window. The second bird is that it’s actually creating electricity for you … during a large part of the day,” Sivaram said. He also delivered a keynote on innovation in R&D on the previous day.

As for perovskite’s reliability issues, Sivaram said researchers will solve them – and need to.

“I don’t think that if we stay on the current path of incremental technology improvement, taking today’s technologies and making them a little better and a little better, that we’ll get to where we need to be tomorrow. … We really need to plan for solar that’s far cheaper than it is today. Solar that’s far cheaper needs to look much different. It’s not going to be silicon.”

Pricing Innovation

Cost is the prime motivator for the field. Vermeersch is moving his lab to a model in which the levelized cost of electricity (LCOE) is a key factor.

“Efficiency is the major lever to decrease the cost of electricity. This is not the only one. The lifetime is significant as well. But efficiency is the major leveler to decrease the cost of electricity and coming to perovskite, for example, for me the right metrics to know if it’s worth or not to put a perovskite layer on top of silicon is, again, the LCOE. Because if you get an extra 2% of efficiency on the 24% silicon cell, then probably the cost of electricity will not go down. It will go up because of the cost of putting this perovskite layer,” said Vermeersch.

Expect more announcements on perovskite and its commercial potential in the new year.

This piece was also published on Informa Energy Group's Energising the Industry.