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xenon54xenon54 t1_iqwhs8k wrote

Researchers made a two-junction solar cell with silicon and perovskite. To my knowledge, this is the highest efficiency solar cell which uses perovskite. However, this is still a multijunction cell, and the problem with multijunction cells over pure silicon or other single-layer cells is that despite potentially doubling the efficiency of the cell, it increases the cost by an order of magnitude simply because of the added manufacturing complexity. The problem with deploying PV en masse is cost/watt, not area/watt. Only satellites and other PV vehicles can benefit from the smaller area and mass of multijunction cells to the degree needed to offset the massively higher fabrication cost.

That being said, if this technology can be applied cheaply, that is, for less than double the original price of a cell, then the improved power density may actually be worth it, at least for small installations such as rooftop or canopy PV.

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jacky4566 t1_iqx4mt5 wrote

You also need 2x the solar controllers which are also not cheap.

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Lejeune_Dirichelet t1_ir2n3ts wrote

> The problem with deploying PV en masse is cost/watt

Labour and transport costs are now a significant portion of solar installation costs. More watts/panels therefore improves cost/watt.

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xenon54xenon54 t1_ir2u4cz wrote

Let's say most of the total cost of a PV array are from installation with option A. Let's say that option B shifts the balance towards panel price because it's easier to install, but the panels are more expensive. Option B is better than option A if, for the same price, more capacity can be installed. Therefore, if option B increases the price of the panels by more than it reduces the price of installation compared to A, it is worse. Let A have a levelized, $/kw installation price of $20 and a panel price of $80. If B is twice as easy to install than A, for instance, it requires half as many panels to be installed, then as long as the price of the panels increase by less than $10, or ~12% of the price of the panels in A, it is the preferable option.

Here's the problem: even if the panels installed themselves, you can only save a maximum of 20% over option A without also making the panels cheaper on a per-watt basis. Unless panels get obscenely expensive to install compared to the price of each panel, it is very difficult to decrease cost by increasing the efficiency of the panel, because high efficiency, tandem cells such as the one in this article cannot be manufactured more cheaply than existing silicon cells. CVD is obscenely difficult and slow compared to mono-silicon production.

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