Interesting developments in solar panel efficiency

[booke23]

I was listening to Radio 4 yesterday and happened to catch this program https://www.bbc.co.uk/programmes/m000r3nn 

 

It was highlighting the fact that current solar panels only make use of 20% of the light spectrum that hits it, and panels are in development that (within 10 years) will be producing double the power that current panels do. Makes for quite interesting listening.  

[MtB]

2 minutes ago, booke23 said:

I was listening to Radio 4 yesterday and happened to catch this program https://www.bbc.co.uk/programmes/m000r3nn 

 

It was highlighting the fact that current solar panels only make use of 20% of the light spectrum that hits it, and panels are in development that (within 10 years) will be producing double the power that current panels do. Makes for quite interesting listening.  

 

The power output from the sun arriving at the earth, measured at the equator with the sun directly overhead, is near as dammit 1kW per square metre, yet our current solar panel technology harvests at best only 20% of this. So there is plenty of theoretical scope for improvement.

 

Anyway thanks for the link, I'd heard a trailer for this programme then missed it! Will listen now...

[reg]

3 hours ago, MtB said:

 

The power output from the sun arriving at the earth, measured at the equator with the sun directly overhead, is near as dammit 1kW per square metre, yet our current solar panel technology harvests at best only 20% of this. So there is plenty of theoretical scope for improvement.

 

Anyway thanks for the link, I'd heard a trailer for this programme then missed it! Will listen now...

This appears to be the current state of play for bulk space panels

https://www.pv-magazine.com/2022/03/10/rocket-lab-unveils-space-solar-cell-with-33-3-efficiency/

 

A good decade ago I did meet someone near Foxton who was working on space solar panel research and at that time they had got them up to 31%.

But these, if I recall correctly, were not bulk production units. 

 

[IanD]

1 hour ago, reg said:

This appears to be the current state of play for bulk space panels

https://www.pv-magazine.com/2022/03/10/rocket-lab-unveils-space-solar-cell-with-33-3-efficiency/

 

A good decade ago I did meet someone near Foxton who was working on space solar panel research and at that time they had got them up to 31%.

But these, if I recall correctly, were not bulk production units. 

 

 

Small panels in the laboratory have been pushed up far higher than this (over 45%) using multiple layers and exotic materials. The problem is that there's zero chance of these ever making it into mass production, because the manufacturing costs are far higher than conventional panels. The "space-quality" ones in the link get up to more than 30%, but the cost is also astronomical 🙂

 

What matters in 99% of panels is cost per kW not absolute efficiency, silicon solar panels are made cheaply in huge volumes from low-cost materials, and the best ones are currently around 22% efficient. There are some ideas on how to push this up and keep cost low (e.g adding perovskite layers) but this will only give a few percent more efficiency. It's possible that this might be improved in future, but big jumps in efficiency tend to need multiple layers or scarce materials which puts the cost up and makes it impossible to scale up to volume production -- a panel with 25% higher output but 2x the price is never going to succeed.