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  • Solar power is a key piece of most plants for a carbon neutral energy future.

  • While silicon based solar cells are by far the most common technology, one relative newcomer, solar cells that use perovskite crystals, has been getting better by leaps and bounds.

  • At this rate, perovskite solar cells could become an attractive alternative to silicon in the near future.

  • Or the two types of solar cells could join forces to take solar power to new heights.

  • Perovskites are a class of materials that have a cube like and diamond like crystal structure.

  • So the first perovskites were discovered more than 180 years ago.

  • They were only applied to solar cells within the last two decades.

  • They work the same way other semiconductor based solar cells do.

  • Light from the sun excites electrons in the material and those electrons flow to conducting electrodes and generate a current.

  • In 2006, perovskite cells were about 3% efficient, fast forward to 2020 and some researchers were boasting 25% efficiency.

  • For comparison, the first silicon solar cells were created in a lab as far back as 1940.

  • In the 80 years since then, they've matured steadily to the point where they are now typically 15% to 20% efficient.

  • It's true that silicon cells are getting cheaper all the time, but they're still relatively expensive and difficult to make.

  • Perovskite cells, on the other hand, can be made with simpler manufacturing processes, like printing the crystals onto a surface, so they have the potential to be much cheaper.

  • Wait, it gets better.

  • Because perovskite are artificial, they can be designed to be most efficient at certain wavelengths, meaning they can work in tandem with silicon in a solar cell to generate electricity from light that silicon can't use.

  • These tandem solar cells are already a hair's breadth from 30% efficiency and still have room for improvement.

  • It's also possible to paint perovskite crystals onto a surface, meaning you could literally paint your house into a solar panel.

  • You know, provided your house's exterior is made of materials that can conduct the electricity the crystals generated.

  • Just, you know, that caveat.

  • Oh hey, look at that.

  • We are at the halfway point of the video, and everything I've said about the technology thus far has been glowing.

  • You know what that means, right?

  • There's a but coming, and here it is.

  • Perovskite solar cells have amazing potential, but they still face a few challenges before they'll be commercially viable.

  • One major challenge is degradation.

  • While silicon cells can last 25 years or more, perovskite aren't anywhere close to that.

  • Their performance drops off in the span of months rather than years.

  • The material is fragile and degrades when exposed to moisture, oxygen, high heat and... light.

  • A solar cell that breaks down when exposed to light is, shall we say, less than ideal.

  • It's also difficult to make large perovskite cells to maintain high efficiency.

  • Pinholes and impurities between the grains can hinder the flow of current, and these problems get worse over larger areas.

  • These defects also give humidity and oxygen a foothold to start breaking down the material, so, larger perovskite cells degrade faster.

  • And finally, there is the issue that a major component of the crystals themselves is lead.

  • Either the toxicity and environmental concerns of using lead will have to be addressed, or researchers will have to find an alternative.

  • Despite all that, it's still incredible just how far perovskite solar cells have come in such a short amount of time.

  • The next generation of solar cells that use perovskite and silicon in tandem could be hitting the market as soon as 2022.

  • In terms of efficiency, perovskites have caught and surpassed the most established solar power technology there is in the span of just 15 years.

  • New breakthroughs, inefficiency, lifespan and scalability are happening all the time.

  • If researchers can keep up that piece of innovation, the future of solar power looks very bright indeed.

  • To learn more about how exactly solar panels work, check out this illuminating light speed episode here.

  • Thanks so much for watching.

  • Be sure to hit that subscribe button and I will see you next time on seeker.

Solar power is a key piece of most plants for a carbon neutral energy future.

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B2 solar silicon peroxide solar power tandem efficiency

How Crystals Can Turn Any Surface Into a Solar Panel

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    林宜悉 posted on 2021/04/16
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