Published on May 17th, 2018 | by Tina Casey0
When Perovskite Solar Cells Are Cheap As Glass, What Then?
May 17th, 2018 by Tina Casey
Researchers at The Fraunhofer Institute for Solar Energy Systems in Germany have come up with a business model that could upend the global solar marketplace. If it all works out, practically any facility that manufactures glass could churn out low cost perovskite solar cells for local markets. Aside from making solar panels cheaper, the local angle also reduces transportation costs and avoids sticky trade issues like the new US solar tariff.
Perovskite Solar Cells Are Already Cheap…
CleanTechnica has spilled a lot of ink over perovskites over the past couple of years. They’re a class of lab-grown crystals that mimic the structure of natural perovskite, a mineral with good potential for solar applications (check out our sister site Solar Love for more coverage).
One of those challenges is that perovskites degrade when exposed to air. Yes, air. The good news is that researchers have been developing workarounds to fix the problem, so there’s that.
…And They’re About To Get Cheaper.
All this brings us right around to the new perovskite research from Fraunhofer ISO. The team, spearheaded by Dr. Andreas Hinsch, focuses on building sustainability into the materials and manufacturing process for perovskite solar cells, without compromising efficiency.
Low cost manufacturing generally involves cutting the number of steps down to a minimum, using less material, using inexpensive material, and avoiding temperature extremes. With that in mind, the team came up with a new, more precise method of “printing” a perovskite solar cell:
…the researchers around Hinsch have found a way to convert the perovskite to a molten salt at room temperature using a polarized gas, and so were able to fill the pores of the electrode. The final desorption of the gas greatly increases the melting point and brings about the crystallization. The result is a homogenous growth process.
The solar conversion efficiency end of the exercise came out to a respectable 12.6%, which the lab states is a new record for printed solar cells.
So far the research has been confined to small solar cells, so the next step is scaling up.
You can get all the details from the journal Nature under the title “Distinguishing crystallization stages and their influence on quantum efficiency during perovskite solar cell formation in real-time,” and in ACS Energy Letters under “High Photovoltage of 1 V on a Steady-State Certified Hole Transport Layer-Free Perovskite Solar Cell by a Molten-Salt Approach.“
Meet Your Friendly Neighborhood PV Maker
Faunhofer ISO notes that “the processing steps used for the 12.6% solar cell are similar to those used in the glass industry.” That opens up the potential for introducing perovskite solar manufacturing into local facilities, without the need for the elaborate infrastructure demanded by conventional silicon solar cell manufacturing.
Now, add the use of inexpensive materials (graphite and perovskite), and you arrive at a business model in which your biggest expense is the glass, not the PV material. Fraunhofer explains:
…This means that based on the low material costs, the share of the transport costs become so significant that production and sales at a local level could compete with centralized production.
So, when can your local glass artisan start creating beautiful one-of-a-kind perovskite solar cells? The Glass Art Society has hundreds of members, so find one near you and ask them about it.
If the artists are not yet ready for the perovskite revolution, perhaps commercial-scale operations are. The Glass Manufacturing Industry Council only lists a handful of members in the “melter” category so turn to Glass Magazine’s 2016 list of top glass manufacturers to get an idea of the scope of the industry in the US.
Last year was a challenging one for the industry. Our new friends over at Glass Magazine report that an unusual series of mishaps at major facilities put a serious crimp on the glass supply in 2017. A tight labor market and logistics issues also contributed to difficulty in keeping up with demand.
The good news is that US glass manufacturing is on the rebound this year. Most of the damage to manufacturing facilities has been repaired, several large US companies plan on ramping up production, and our neighbors to the north and south are upping their game, too. Check this out:
North America will also see a long-term injection of float supply with new glass plants. Saint-Gobain announced plans to open a new float production line in Saltillo, Mexico, that is scheduled to become active in 2020. Additionally, leading Chinese glass manufacturer Xinyi Glass announced in November plans to build a $450 million float glass plant in Ontario, Canada…
We’ve reached out to NREL for some additional insights on how the relationship between perovskite solar cells and glass manufacturing could pan out in the US, so stay tuned for more on that.
So, where does this leave President* Trump’s solar tariff? A slowdown in US solar job creation in 2017 has been attributed to worries over the new tariff, but when the tariff finally did go into effect last February the industry hit the rebound button.
The solar industry is here to stay regardless of policies set by the White House, and if the Fraunhofer business model goes mainstream you could see solar cells that cost little more than a pane of glass…eventually!
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*As of this writing.