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Efficiency as measured in the lab is the wrong metric for solar panels. If you want to buy solar panels, you go for the Levelized Cost of Electricity (LCOE). I

Efficiency as measured in the lab is the wrong metric for solar panels. If you want to buy solar panels, you go for the Levelized Cost of Electricity (LCOE). It looks at the cost of electricity of the entire system over its lifetime. It takes interest on loans, cost of panels, inverters, installation cost, labour cost, insurance and the geographic location into account. It turns out that in most cases a lower efficiency panel built cheaply is better, for example a bifacial panel upright on the ground instead of on a roof (lower labour cost) wins. Even old inefficient second hand panels can outperform a high efficiency solar panel over its lifetime. We build $0,04 single chip solar cell MPPT inverters (72-122 per solar panel) that for various reasons yield 30% more electricity while also lowering manufacturing (less glass, smaller panels, cheaper inverters with higher efficiency, thinner wires) and installation cost. We expect solar electricity cost to keep dropping far below 1 cent per kWh. Eventually we'll grow solar panels (for example from captured CO2) over the next decades with nanotech manufactoring methodes (atom by atom) until they will be virtually free, like plants. In this light, the Oxford efficiency metric for future solar panels might be bypassed by other cheaper systems that are less efficient.

vlovich123 3y ago
But these kinds of things come down in price over time. This is just basic research, not commercialized. Another important metric is how much physical space is needed by the panels and higher efficiency means less space. There’s never a single metric that you can use to decide “better” - it depends on the needs of the project.
- morphle 3y ago
  All these kinds of solar cell systems come down in price over time, not just this Oxford PV research when (and if) it goes into mass production. I agree that there is no single metric to decide "better". But in most cases properly calculated LCOE, the cost of a kWh over the lifetime of the solar panel system is the single metric that matters. Because why pay more for electricity? Only in special projects, like solar panels in space, cost is not the most important metric.
  - akamaka 3y ago
    From what I’ve read, panels are sometimes only a quarter of the price of a residential solar installation. In that case, if the panel cost twice the price for only 25% more power, it might be worth it.
    - morphle 3y ago
      Indeed. For example utility scale solar can be less than 30% the cost of a residential solar installation, but also adds profit margins, interest rates and distribution costs to a residential customer. In the later Ringworld books Larry Niven introduced solar 'panels' sprayed onto any surface and wirelessly broadcasting power. The DIY installation costs would now be almost zero.
      - midasuni 3y ago
        What’s the cost of domestic installation on a new house? I was looking at some builders adding a roof the other day, putting panels on at the same time wouldn’t add much in labour.
        rcxdude 3y ago
        It is cheaper, especially if you build the modules into the roof, as you then don't need the roof materials. It still suffers a little from being specialist, and so more expensive regardless of material costs.
        midasuni 3y ago
        But it’s a tiny amount, the work isn’t that specialist or hard to learn, the scaffolding is already in place. One or two days labor at most?
        morphle 3y ago
        The cost of domestic installation on a new house varies wildly worldwide. In the USA labour and permitting cost dominate, rooftop solar installation costs are almost double what they are in Australia or the Netherlands, where they have the highest percentage of rooftop solar installation.
pwagland 3y ago
You are correct of course. The main point of research like this is to drive development of panels forward. That helps to drive the cost of the panel down as well. A similar argument can be made for almost any good, over the lifetime of the good, within an application category, second hand will often be better. However, in general, it is still useful better technology, so that newer models can be more efficient, which eventually trickle down to older models becoming more efficient.
- morphle 3y ago
  You are referring to Wright’s Law [1]. For more than four decades, the price of solar panels declined by 20% with each doubling of global cumulative capacity[2], but you should check that with many more data sources, especially reputable or scientific sources. [1] https://en.wikipedia.org/wiki/Experience_curve_effects https://en.wikipedia.org/wiki/Experience_curve_effects [2] https://ourworldindata.org/learning-curve https://ourworldindata.org/learning-curve
amluto 3y ago
If you’re willing to put multiple MPPTs on a panel, then I imagine the benefits of higher efficiency multilayer panels are actually amplified a bit. You can spend a bit more on the panel, but you need fewer panels for the same capacity, and panels are getting cheap enough that the balance of the system (mounting, wires between panels, etc) are quite significant. Who is the “we” that builds these tiny MPPTs? I’m curious.
- morphle 3y ago
  "We" is my small 20 year old Metamorph Research Institute and our spinoff companies Morphle Inc and Fiberhood Coöperation. Apologies, my websites are down and I still need to publish the science papers on the tiny MPPT chips and microcontrollers. We also design the largest chips [1] and I build Enernet microgrids [2] based on our chips. We are chip designers and made a 1 dollar cent 64 bit 8 core microprocessor with MPPT and bidirectional buck/boost flyback inverters built-in. This nanoinverter can take the <0.5V of a single solar cell and convert it to (for example) 6V. Because these nanoinverters are networked over the DC conducters to each other, they can aggregate their output voltage to 48V, 110V or much higher so the conductors become much thinner. With all the power transistors, opamps, capacitors and diodes integrated into the chip you save more than $50 on discreet component MPPT and microinverters per panel while also boosting the MPPT per cell thus mitigating almost all shading losses. The same chip can also charge/discharge (lithium and other) batteries. You can get 20 times more cycling charges out of Li-ion this way but you also save on the charging inverters. A single nano-inverter chip can take the output of one or more solar cells and charge li-ion cell, saving you half the number of nano-inverter chip in a total system. I still need $50K investment to start the mass production of the new model 180nm chips, that will drop the manufacturing cost to 1 cent. Sadly Ycombinator won't fund me as they dislike single founders and dislike funding hardware startups.If you know anyone who can help us with sales or funding please send me an email. A competitor already manufactors solar panels with microinverters for strings of cells (6-8 per panel) but their panels cost so much more that it is not worth it. Our nanoinvertors are two orders of magnitude cheaper. [1] https://vimeo.com/731037615 https://vimeo.com/731037615 [2] https://www.researchgate.net/profile/Merik-Voswinkel/publication/309254511_Fiberhood_Smart_Grid/links/5807410c08ae5ad1881691e3/Fiberhood-Smart-Grid.pdf https://www.researchgate.net/profile/Merik-Voswinkel/publica...
HPsquared 3y ago
Land, and space in general, also costs money. Higher efficiency cells get more energy per unit area. So the effect on LCOE depends on how big that factor is.
- morphle 3y ago
  Indeed. LCOE means taking all cost factors into account, not just efficiency or land cost. Rarely does a LCOE calculation cover all these costs, so the published numbers are still hard to compare.

vlovich123 3y ago

But these kinds of things come down in price over time. This is just basic research, not commercialized. Another important metric is how much physical space is needed by the panels and higher efficiency means less space. There’s never a single metric that you can use to decide “better” - it depends on the needs of the project.

morphle 3y ago
All these kinds of solar cell systems come down in price over time, not just this Oxford PV research when (and if) it goes into mass production. I agree that there is no single metric to decide "better". But in most cases properly calculated LCOE, the cost of a kWh over the lifetime of the solar panel system is the single metric that matters. Because why pay more for electricity? Only in special projects, like solar panels in space, cost is not the most important metric.
- akamaka 3y ago
  From what I’ve read, panels are sometimes only a quarter of the price of a residential solar installation. In that case, if the panel cost twice the price for only 25% more power, it might be worth it.
  - morphle 3y ago
    Indeed. For example utility scale solar can be less than 30% the cost of a residential solar installation, but also adds profit margins, interest rates and distribution costs to a residential customer. In the later Ringworld books Larry Niven introduced solar 'panels' sprayed onto any surface and wirelessly broadcasting power. The DIY installation costs would now be almost zero.
    - midasuni 3y ago
      What’s the cost of domestic installation on a new house? I was looking at some builders adding a roof the other day, putting panels on at the same time wouldn’t add much in labour.
      - rcxdude 3y ago
        It is cheaper, especially if you build the modules into the roof, as you then don't need the roof materials. It still suffers a little from being specialist, and so more expensive regardless of material costs.
        midasuni 3y ago
        But it’s a tiny amount, the work isn’t that specialist or hard to learn, the scaffolding is already in place. One or two days labor at most?
      - morphle 3y ago
        The cost of domestic installation on a new house varies wildly worldwide. In the USA labour and permitting cost dominate, rooftop solar installation costs are almost double what they are in Australia or the Netherlands, where they have the highest percentage of rooftop solar installation.

pwagland 3y ago

You are correct of course. The main point of research like this is to drive development of panels forward. That helps to drive the cost of the panel down as well. A similar argument can be made for almost any good, over the lifetime of the good, within an application category, second hand will often be better. However, in general, it is still useful better technology, so that newer models can be more efficient, which eventually trickle down to older models becoming more efficient.

morphle 3y ago
You are referring to Wright’s Law [1]. For more than four decades, the price of solar panels declined by 20% with each doubling of global cumulative capacity[2], but you should check that with many more data sources, especially reputable or scientific sources. [1] https://en.wikipedia.org/wiki/Experience_curve_effects https://en.wikipedia.org/wiki/Experience_curve_effects [2] https://ourworldindata.org/learning-curve https://ourworldindata.org/learning-curve

amluto 3y ago

If you’re willing to put multiple MPPTs on a panel, then I imagine the benefits of higher efficiency multilayer panels are actually amplified a bit. You can spend a bit more on the panel, but you need fewer panels for the same capacity, and panels are getting cheap enough that the balance of the system (mounting, wires between panels, etc) are quite significant. Who is the “we” that builds these tiny MPPTs? I’m curious.

morphle 3y ago
"We" is my small 20 year old Metamorph Research Institute and our spinoff companies Morphle Inc and Fiberhood Coöperation. Apologies, my websites are down and I still need to publish the science papers on the tiny MPPT chips and microcontrollers. We also design the largest chips [1] and I build Enernet microgrids [2] based on our chips. We are chip designers and made a 1 dollar cent 64 bit 8 core microprocessor with MPPT and bidirectional buck/boost flyback inverters built-in. This nanoinverter can take the <0.5V of a single solar cell and convert it to (for example) 6V. Because these nanoinverters are networked over the DC conducters to each other, they can aggregate their output voltage to 48V, 110V or much higher so the conductors become much thinner. With all the power transistors, opamps, capacitors and diodes integrated into the chip you save more than $50 on discreet component MPPT and microinverters per panel while also boosting the MPPT per cell thus mitigating almost all shading losses. The same chip can also charge/discharge (lithium and other) batteries. You can get 20 times more cycling charges out of Li-ion this way but you also save on the charging inverters. A single nano-inverter chip can take the output of one or more solar cells and charge li-ion cell, saving you half the number of nano-inverter chip in a total system. I still need $50K investment to start the mass production of the new model 180nm chips, that will drop the manufacturing cost to 1 cent. Sadly Ycombinator won't fund me as they dislike single founders and dislike funding hardware startups.If you know anyone who can help us with sales or funding please send me an email. A competitor already manufactors solar panels with microinverters for strings of cells (6-8 per panel) but their panels cost so much more that it is not worth it. Our nanoinvertors are two orders of magnitude cheaper. [1] https://vimeo.com/731037615 https://vimeo.com/731037615 [2] https://www.researchgate.net/profile/Merik-Voswinkel/publication/309254511_Fiberhood_Smart_Grid/links/5807410c08ae5ad1881691e3/Fiberhood-Smart-Grid.pdf https://www.researchgate.net/profile/Merik-Voswinkel/publica...

HPsquared 3y ago

Land, and space in general, also costs money. Higher efficiency cells get more energy per unit area. So the effect on LCOE depends on how big that factor is.

morphle 3y ago
Indeed. LCOE means taking all cost factors into account, not just efficiency or land cost. Rarely does a LCOE calculation cover all these costs, so the published numbers are still hard to compare.