Solar panel efficiency is based on how well a solar panel converts sunlight into electricity. A more efficient panel produces more electricity than a less efficient one, given the same amount of sunlight. Solar panels use solar cells to achieve this, along with other parts like wiring, surge protectors, switches, etc.

The maximum possible efficiency of solar cell designs as of 2019 is 33.7%. In practice, however, efficiency tends to be lower because of factors like environmental conditions (high temperatures decrease efficiency, humidity causes corrosion), design, materials, and manufacturing methods.*

Today's labs demonstrate performance that exceeds what's in practical use, but the high cost of production often prevents their widespread use.

Crafting a better means of production

Atomically precise manufacturing (APM) will let us produce solar panel components, and thus solar panels, at very low cost with high reliability, and on a vast scale. It enables this by building things from the ground up using self-assembling molecular machines. This makes it easier to eliminate wasteful products, reduce errors in the manufacturing process, and produce better-fitting or seamless parts.

As a rough analogy, consider the video game Tetris.** With lots of small shapes of different orientations, you can rotate each one to fit a corner just right without leaving a space, building complete horizontal lines. If instead the game gave you huge blocks of different shapes to arrange in the same limited space, you'd be less likely to get them to fit together.

A similar principle applies in APM. Less unwanted space between components at the nanoscale gives you stronger, defect-free products.

APM is one kind of nanotechnology, and will be the most efficient way to make highly efficient solar panels.

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* Greentumble. "Why are Solar Panels Inefficient?" APRIL 27, 2018 https://greentumble.com/why-are-solar-panels-inefficient/

** Super Puzzle Fighter II Turbo might be a better analogy, as you're trying to organize blocks by to form large structures of the same color, and not just complete horizontal lines like in Tetris. This is (more closely) analogous to having atoms and molecules with distinct properties. Hmmm... Molecular Minecraft anyone?

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