9 ms·

Next-generation solar cells pass strict international tests

146 points by headalgorithm 6y ago

bufferoverflow 6y ago
TL;DR: 500 times thinner, much cheaper, 25.2% efficiency, but not durable at all.
- phkahler 6y ago
  Now they have a coating that protects them. TFA did not say how much that changed efficiency, if at all.
darksaints 6y ago
I've passively followed the perovskite revolution for a while now, and the constant claim is that they're cheaper. But how cheap? Nobody can ever seem to quantify it.
- jayrot 6y ago
  No idea if it applies here or not, but a general rule of thumb is if they don't how say how much cheaper...it's not that much cheaper. "new solar cells are 94% of the price than existing mono-crystalline cells"
- philipkglass 6y ago
  The raw materials for perovskite cells are cheap, but so are the raw materials for silicon cells. There won't be hard cost numbers on perovskite PV modules until they go into volume manufacturing. They won't go into volume manufacturing until they can be stabilized enough to last years in the field. My personal guess is that single-junction perovskite cells will not ever overtake single-junction silicon cells for rooftop or utility scale solar. Single junction perovskite cells may be used in applications where light weight and flexibility are advantageous, like charging portable electronics, if they can be stabilized. Perovskite cells may compete in rooftop/utility solar with conventional silicon when incorporated into tandem cell designs -- either perovskite on silicon or a stack of different perovskites with different band gaps. That gives them the potential to exceed conventional crystalline silicon module efficiency rather than merely play catch-up. The company that seems to be furthest along with this approach is Oxford PV, which is pursuing a perovskite/silicon tandem design: https://www.oxfordpv.com/perovskite-silicon-tandem https://www.oxfordpv.com/perovskite-silicon-tandem
  - powerslacker 6y ago
    Full disclosure, I know next to nothing about solar markets. What about putting panels on vehicles? Couldn't the market for cells on vehicles overtake the existing solar market?
    - philipkglass 6y ago
      There isn't enough surface area on vehicles for that to happen. The world installed about 117 gigawatts (peak) of solar PV last year [1]. If the average panel is 17% efficient that's more than 680 million square meters of panels being manufactured per year. World motor vehicle production in 2018 was 96 million [2]. To put more solar panels on vehicles than we already put in fields and on rooftops, the average vehicle would need more than 7 square meters of surface covered with panels. That's neglecting that most vehicles are still internal combustion vehicles that couldn't do much with the electricity those panels would generate. [1] https://en.wikipedia.org/wiki/Growth_of_photovoltaics https://en.wikipedia.org/wiki/Growth_of_photovoltaics [2] https://en.wikipedia.org/wiki/List_of_countries_by_motor_vehicle_production https://en.wikipedia.org/wiki/List_of_countries_by_motor_veh...
      - woodandsteel 6y ago
        >There isn't enough surface area on vehicles for that to happen. Yeah, it's the old square-cube law in action.
    - nimos 6y ago
      Just not enough room really. Maybe(read: no) you could get 5m^2 of panels on a car. With 100% efficient panels the energy would be 5 * 1000 W m^2 = 5000 watts which is about 7 horse power. That is a bit below what a very aerodynamic car needs to maintain highway speed so sort of relevant from a range extension perspective but 100% efficient panels and 5m^2 being fully illuminated at once are not very realistic assumptions. I could see electric trucks(non commuting) + tiny home on wheel with big arrays potentially being viable though. That + starlink would make a pretty cool working remote combo.
    - 6y ago
- kragen 6y ago
  If you're making something in a laboratory, it's not cheap, even if it could conceivably be cheap in mass production. Even once something is in mass production — like silicon PV has been for the last 40 years — it can take a long time to bring the cost down. Silicon PV cells have fallen in cost by a factor of 10 in the last 10 years, in part due to much higher volumes, in part because the production lines no longer need to be staffed by Ph.D.s. Who could have predicted in 1980 that that would take until 2015? In a lab you can demonstrate how much material something uses, how long it lasts under given conditions, and, say, how sensitive it is to contamination. But you can't predict, you know, the late-oughties polysilicon price bubble, the ensuing long-term purchase agreements made by companies like Evergreen, and the subsequent polysilicon price collapse that sunk those companies. (I'm still not sure where modern PV cell companies source their silicon! Is it UMG?) "How cheap?" is a question about international trade, mining, and management, not a question about materials science. Don't expect materials scientists to be able to answer it.
henearkr 6y ago
IIRC, there are some nasty heavy metals in some perovskites. Does anybody know which type is used in these projects? I'm 3000% in favor of solar, but still it bothers me if they use Pb etc...
- borkt 6y ago
  I focused on PV in college and the fact is solar is dirty and they haven't planned for end of life recycling. The potential is great and we will get there im sure, but I always thought it was irresponsible to subsidize and widely roll out especially the early stuff in the 90s that was very inefficient and filled with heavy metals and REE. I'm not up to date now but the only thing I can say is at least the efficiency is better even if they are using similarly toxic elements.
  - gibolt 6y ago
    The amount of oil or natural gas for the equivalent amount of energy that will be saved is worth it. Old panels were bad, but without it we wouldn't have today's cheap and efficient panels, with more drops to come. Just like with batteries, recycling will become more profitable and thus researched as we march forward
    - drcross 6y ago
      Batteries being made today will last 30 years, the first 15 will most likely be in a car and after that in a house battery. In 30 years we'll have drastically different ways of coping with waste so this concern about recycling is such a red herring.
      - alacombe 6y ago
        If "recycling details" can be figured out later, then the same argument can be used to justify a massive investment in nuclear power, ie. 4th generation reactor, LFTR, you name it. It would generate more energy over its lifetime than PV ever would.
roenxi 6y ago
The uncertainties here are demonstrated by the fact that the article is quoting 25.2% efficiencies. Solar panel efficiency wouldn't matter as much as the ratio of energy/m2/$ ratio. Nobody cares if a solar panel is 2% efficient if it costs 100 times less to fabricate and install. Just build more of them. Still, it is good news to see this sort of energy research bearing fruit.
- nimos 6y ago
  At 2% efficient and 0 cost they would probably be more expensive than current when looking at total installed cost for commercial/residential, maybe even utility. You can see even at utility scale the panel prices are generally less than 50%.[1] I think 2018 increase was tariff related. Been out of the industry ~5 years so don't follow stuff that closely. Many of the other costs are basically a multiple of # of panels which would be 10x at 2% efficiency. [1]https://www.nrel.gov/docs/fy19osti/72399.pdf https://www.nrel.gov/docs/fy19osti/72399.pdf
  - roenxi 6y ago
    I did say fabricate and install you'll notice. If they came up with something really light and cheap to produce installation costs would plummet. Compare the cost of installing windows to installing solar panels - windows don't even have a rate of return but everyone has windows. It is a no-brainer to install windows. Solar panels are not a no brainer decision (yet, hopefully). And that was the point - weight and difficulty of transporting the final system is a very important variable. Probably more important than efficiency when orders of magnitude are concerned. From a 25% base efficiency can double and double then it stops improving. Weights and installation costs due to the panel technology can halve and halve and halve and so on - and each halving reduces the cost of transporting the panels. There are more gains to be made there. It would be worth trading efficiency away to make big gains there.
- Gravityloss 6y ago
  Solar cells have been getting quite cheap. At some point covering materials and installation cost start to have an effect - and those are smaller with better efficiency.
kitotik 6y ago
So is part of the bet here that future potential efficiency numbers will continue to increase at a rate faster than silicon can? Or is strictly a low cost play?
- ResearchAtPlay 6y ago
  Efficiency improvements amplify cost reduction per kWh electricity: An ever growing share of PV system costs stems from every item that is not a a module (inverter, cables, labour etc). Modules are becoming cheaper faster than other components, so reducing module costs further has diminishing returns. In contrast, taking your module efficiency from 20% to 21% increases electricity generation by 5% and thus reduces costs per kWh by 5%.
econcon 6y ago
Last time I was installing panels, panel were fairly cheap. More expensive were inverter, controller, batteries.
- deleted 6y ago
  [deleted]
kumarski 6y ago
Gonna chime in here, have a weak materials engineering background. The material economics go wild if you try to solve for stability of perovskite. You really don't know how much this thing is going to cost. With perovskite, from what I remember, you get the nice efficiencies with lead based perovskites. This increases the price of electricity as you layer it on top and you get an extra 2% efficiency.
Fielddisturb 6y ago
Low cost energy? Think twice, the population is controlled by this expense mostly! It's a nice utopian dream, scientifically achievable, but politically not viable.
einpoklum 6y ago
We should always remember additional factors to the equation, including: * The materials involved in production of such cells and of power-stations/fields based on them - in particular, their rarity and/or their toxicity. * The sustainability and environmental impact of procuring the materials. * Longevity of the cells. * Recyclability / decomposability of the cells at end-of-life. * Logistical considerations in setting up and operating solar cell fields, specifically of this type. * Ease/cost/frequency of maintenance on these cells, individually and in a solar-field, when in operation. and perhaps other factors I'm forgetting. Still, the materials science achievement is to be lauded.
- m463 6y ago
  Your comment seems very general. It would be better to address perovskite cells specifically.
- xiphias2 6y ago
  The article talks about these things: - Increasing the longevity of the cells is the main achievement of the research. - Gas-spectromenty should help in understanding the toxicity as well - Something that's 200 cheaper than the current material and scalable can't be rare at the same time.
- BiteCode_dev 6y ago
  Anything using fossil energy also has such hidden issues. And you have to consider the ecosystem: - fossil fuel engines require much more maintenance than electrical engines, and now vehicules always embed heavy electronics anyway. - fuel need to be transported at a heavy cost, which is now hidden by the massive demand. The day we use more solar than fossil, the whole fossil infra will suddenly feels very expensive - most countries are not like the US and don't have oil on their soil. Countries don't like to be dependant on others for critical things. You may buy solar panels (or fuel engine) from a friendly country, but if things turn out badly, people can't cut sunlight from you one the initial setup is there. Nothing is perfect of course, but I like the solar future we are hinted at.
  - 6y ago
jsingleton 6y ago
This is a great long read (if you like log graphs) on how solar prices have dropped more than anyone predicted: https://rameznaam.com/2020/05/14/solars-future-is-insanely-cheap-2020/ https://rameznaam.com/2020/05/14/solars-future-is-insanely-c... > This incredible pace of solar cost decline, with average prices in sunny parts of the world down to a penny or two by 2030 or 2035, is just remarkable. Building new solar would routinely be cheaper than operating already built fossil fuel plants, even in the world of ultra-cheap natural gas we live in now. This is what I’ve called the third phase of clean energy, where building new clean energy is cheaper than keeping fossil fuel plants running. Even in places like Northern Europe, by the later 2030s we’d see solar costs below the operating cost of fossil fuels, providing cheap electricity in summer months with their very long days in the high latitudes. These prices would be disruptive to a large fraction of already operating fossil fuel power plants – particularly coal power plants, that are far less able to ramp their power flexibly... (hat tip to the Forge the Future newsletter: https://forgethefuture.substack.com/?no_cover=true https://forgethefuture.substack.com/?no_cover=true) I predict a lot of fossil plants will convert to simply providing inertia for grid stabilisation and charge for the service. They won't burn anything any more and may even demolish their stacks and cooling towers. They will just keep their generators and turbines connected to the grid as a big virtual flywheel to dampen spikes in demand / supply and maintain the AC frequency within tolerance.
- jiofih 6y ago
  Seems like that role will also be moved over to battery installations, as they have an instant response time vs long minutes for a plant.
  - akjssdk 6y ago
    Battery installations are still relatively expensive right for the capacity they offer right?
    - ZeroGravitas 6y ago
      That's a very general statement, but solar plus lithium battery storage is now competitive with gas peaker plants and those can grid balance as an extra service.
LockAndLol 6y ago
So encasing the cells in glass stopped decomposition? There was no pressure buildup in the cells? No gasses released? The test says it's 1800 hours of stressful conditions for the cells. Assuming 10h of sunlight per day, that's 180 days of stability. I guess time will tell how long they really last, but it's good news that they surpassed test requirements. And having a 25% conversion rate baseline compared to a ~26% assumed max for silicon is also impressive. I wonder how much they can boost that.

146 points by headalgorithm 6y ago

bufferoverflow 6y ago

TL;DR: 500 times thinner, much cheaper, 25.2% efficiency, but not durable at all.

phkahler 6y ago
Now they have a coating that protects them. TFA did not say how much that changed efficiency, if at all.

darksaints 6y ago

I've passively followed the perovskite revolution for a while now, and the constant claim is that they're cheaper. But how cheap? Nobody can ever seem to quantify it.

jayrot 6y ago
No idea if it applies here or not, but a general rule of thumb is if they don't how say how much cheaper...it's not that much cheaper. "new solar cells are 94% of the price than existing mono-crystalline cells"
philipkglass 6y ago
The raw materials for perovskite cells are cheap, but so are the raw materials for silicon cells. There won't be hard cost numbers on perovskite PV modules until they go into volume manufacturing. They won't go into volume manufacturing until they can be stabilized enough to last years in the field. My personal guess is that single-junction perovskite cells will not ever overtake single-junction silicon cells for rooftop or utility scale solar. Single junction perovskite cells may be used in applications where light weight and flexibility are advantageous, like charging portable electronics, if they can be stabilized. Perovskite cells may compete in rooftop/utility solar with conventional silicon when incorporated into tandem cell designs -- either perovskite on silicon or a stack of different perovskites with different band gaps. That gives them the potential to exceed conventional crystalline silicon module efficiency rather than merely play catch-up. The company that seems to be furthest along with this approach is Oxford PV, which is pursuing a perovskite/silicon tandem design: https://www.oxfordpv.com/perovskite-silicon-tandem https://www.oxfordpv.com/perovskite-silicon-tandem
- powerslacker 6y ago
  Full disclosure, I know next to nothing about solar markets. What about putting panels on vehicles? Couldn't the market for cells on vehicles overtake the existing solar market?
  - philipkglass 6y ago
    There isn't enough surface area on vehicles for that to happen. The world installed about 117 gigawatts (peak) of solar PV last year [1]. If the average panel is 17% efficient that's more than 680 million square meters of panels being manufactured per year. World motor vehicle production in 2018 was 96 million [2]. To put more solar panels on vehicles than we already put in fields and on rooftops, the average vehicle would need more than 7 square meters of surface covered with panels. That's neglecting that most vehicles are still internal combustion vehicles that couldn't do much with the electricity those panels would generate. [1] https://en.wikipedia.org/wiki/Growth_of_photovoltaics https://en.wikipedia.org/wiki/Growth_of_photovoltaics [2] https://en.wikipedia.org/wiki/List_of_countries_by_motor_vehicle_production https://en.wikipedia.org/wiki/List_of_countries_by_motor_veh...
    - woodandsteel 6y ago
      >There isn't enough surface area on vehicles for that to happen. Yeah, it's the old square-cube law in action.
  - nimos 6y ago
    Just not enough room really. Maybe(read: no) you could get 5m^2 of panels on a car. With 100% efficient panels the energy would be 5 * 1000 W m^2 = 5000 watts which is about 7 horse power. That is a bit below what a very aerodynamic car needs to maintain highway speed so sort of relevant from a range extension perspective but 100% efficient panels and 5m^2 being fully illuminated at once are not very realistic assumptions. I could see electric trucks(non commuting) + tiny home on wheel with big arrays potentially being viable though. That + starlink would make a pretty cool working remote combo.
  - 6y ago
kragen 6y ago
If you're making something in a laboratory, it's not cheap, even if it could conceivably be cheap in mass production. Even once something is in mass production — like silicon PV has been for the last 40 years — it can take a long time to bring the cost down. Silicon PV cells have fallen in cost by a factor of 10 in the last 10 years, in part due to much higher volumes, in part because the production lines no longer need to be staffed by Ph.D.s. Who could have predicted in 1980 that that would take until 2015? In a lab you can demonstrate how much material something uses, how long it lasts under given conditions, and, say, how sensitive it is to contamination. But you can't predict, you know, the late-oughties polysilicon price bubble, the ensuing long-term purchase agreements made by companies like Evergreen, and the subsequent polysilicon price collapse that sunk those companies. (I'm still not sure where modern PV cell companies source their silicon! Is it UMG?) "How cheap?" is a question about international trade, mining, and management, not a question about materials science. Don't expect materials scientists to be able to answer it.

henearkr 6y ago

IIRC, there are some nasty heavy metals in some perovskites. Does anybody know which type is used in these projects? I'm 3000% in favor of solar, but still it bothers me if they use Pb etc...

borkt 6y ago
I focused on PV in college and the fact is solar is dirty and they haven't planned for end of life recycling. The potential is great and we will get there im sure, but I always thought it was irresponsible to subsidize and widely roll out especially the early stuff in the 90s that was very inefficient and filled with heavy metals and REE. I'm not up to date now but the only thing I can say is at least the efficiency is better even if they are using similarly toxic elements.
- gibolt 6y ago
  The amount of oil or natural gas for the equivalent amount of energy that will be saved is worth it. Old panels were bad, but without it we wouldn't have today's cheap and efficient panels, with more drops to come. Just like with batteries, recycling will become more profitable and thus researched as we march forward
  - drcross 6y ago
    Batteries being made today will last 30 years, the first 15 will most likely be in a car and after that in a house battery. In 30 years we'll have drastically different ways of coping with waste so this concern about recycling is such a red herring.
    - alacombe 6y ago
      If "recycling details" can be figured out later, then the same argument can be used to justify a massive investment in nuclear power, ie. 4th generation reactor, LFTR, you name it. It would generate more energy over its lifetime than PV ever would.

roenxi 6y ago

The uncertainties here are demonstrated by the fact that the article is quoting 25.2% efficiencies. Solar panel efficiency wouldn't matter as much as the ratio of energy/m2/$ ratio. Nobody cares if a solar panel is 2% efficient if it costs 100 times less to fabricate and install. Just build more of them. Still, it is good news to see this sort of energy research bearing fruit.

nimos 6y ago
At 2% efficient and 0 cost they would probably be more expensive than current when looking at total installed cost for commercial/residential, maybe even utility. You can see even at utility scale the panel prices are generally less than 50%.[1] I think 2018 increase was tariff related. Been out of the industry ~5 years so don't follow stuff that closely. Many of the other costs are basically a multiple of # of panels which would be 10x at 2% efficiency. [1]https://www.nrel.gov/docs/fy19osti/72399.pdf https://www.nrel.gov/docs/fy19osti/72399.pdf
- roenxi 6y ago
  I did say fabricate and install you'll notice. If they came up with something really light and cheap to produce installation costs would plummet. Compare the cost of installing windows to installing solar panels - windows don't even have a rate of return but everyone has windows. It is a no-brainer to install windows. Solar panels are not a no brainer decision (yet, hopefully). And that was the point - weight and difficulty of transporting the final system is a very important variable. Probably more important than efficiency when orders of magnitude are concerned. From a 25% base efficiency can double and double then it stops improving. Weights and installation costs due to the panel technology can halve and halve and halve and so on - and each halving reduces the cost of transporting the panels. There are more gains to be made there. It would be worth trading efficiency away to make big gains there.
Gravityloss 6y ago
Solar cells have been getting quite cheap. At some point covering materials and installation cost start to have an effect - and those are smaller with better efficiency.

kitotik 6y ago

So is part of the bet here that future potential efficiency numbers will continue to increase at a rate faster than silicon can? Or is strictly a low cost play?

ResearchAtPlay 6y ago
Efficiency improvements amplify cost reduction per kWh electricity: An ever growing share of PV system costs stems from every item that is not a a module (inverter, cables, labour etc). Modules are becoming cheaper faster than other components, so reducing module costs further has diminishing returns. In contrast, taking your module efficiency from 20% to 21% increases electricity generation by 5% and thus reduces costs per kWh by 5%.

econcon 6y ago

Last time I was installing panels, panel were fairly cheap. More expensive were inverter, controller, batteries.

deleted 6y ago
[deleted]

kumarski 6y ago

Gonna chime in here, have a weak materials engineering background. The material economics go wild if you try to solve for stability of perovskite. You really don't know how much this thing is going to cost. With perovskite, from what I remember, you get the nice efficiencies with lead based perovskites. This increases the price of electricity as you layer it on top and you get an extra 2% efficiency.

Fielddisturb 6y ago

Low cost energy? Think twice, the population is controlled by this expense mostly! It's a nice utopian dream, scientifically achievable, but politically not viable.

einpoklum 6y ago

We should always remember additional factors to the equation, including: * The materials involved in production of such cells and of power-stations/fields based on them - in particular, their rarity and/or their toxicity. * The sustainability and environmental impact of procuring the materials. * Longevity of the cells. * Recyclability / decomposability of the cells at end-of-life. * Logistical considerations in setting up and operating solar cell fields, specifically of this type. * Ease/cost/frequency of maintenance on these cells, individually and in a solar-field, when in operation. and perhaps other factors I'm forgetting. Still, the materials science achievement is to be lauded.

m463 6y ago
Your comment seems very general. It would be better to address perovskite cells specifically.
xiphias2 6y ago
The article talks about these things: - Increasing the longevity of the cells is the main achievement of the research. - Gas-spectromenty should help in understanding the toxicity as well - Something that's 200 cheaper than the current material and scalable can't be rare at the same time.
BiteCode_dev 6y ago
Anything using fossil energy also has such hidden issues. And you have to consider the ecosystem: - fossil fuel engines require much more maintenance than electrical engines, and now vehicules always embed heavy electronics anyway. - fuel need to be transported at a heavy cost, which is now hidden by the massive demand. The day we use more solar than fossil, the whole fossil infra will suddenly feels very expensive - most countries are not like the US and don't have oil on their soil. Countries don't like to be dependant on others for critical things. You may buy solar panels (or fuel engine) from a friendly country, but if things turn out badly, people can't cut sunlight from you one the initial setup is there. Nothing is perfect of course, but I like the solar future we are hinted at.
- 6y ago

jsingleton 6y ago

This is a great long read (if you like log graphs) on how solar prices have dropped more than anyone predicted: https://rameznaam.com/2020/05/14/solars-future-is-insanely-cheap-2020/ https://rameznaam.com/2020/05/14/solars-future-is-insanely-c... > This incredible pace of solar cost decline, with average prices in sunny parts of the world down to a penny or two by 2030 or 2035, is just remarkable. Building new solar would routinely be cheaper than operating already built fossil fuel plants, even in the world of ultra-cheap natural gas we live in now. This is what I’ve called the third phase of clean energy, where building new clean energy is cheaper than keeping fossil fuel plants running. Even in places like Northern Europe, by the later 2030s we’d see solar costs below the operating cost of fossil fuels, providing cheap electricity in summer months with their very long days in the high latitudes. These prices would be disruptive to a large fraction of already operating fossil fuel power plants – particularly coal power plants, that are far less able to ramp their power flexibly... (hat tip to the Forge the Future newsletter: https://forgethefuture.substack.com/?no_cover=true https://forgethefuture.substack.com/?no_cover=true) I predict a lot of fossil plants will convert to simply providing inertia for grid stabilisation and charge for the service. They won't burn anything any more and may even demolish their stacks and cooling towers. They will just keep their generators and turbines connected to the grid as a big virtual flywheel to dampen spikes in demand / supply and maintain the AC frequency within tolerance.

jiofih 6y ago
Seems like that role will also be moved over to battery installations, as they have an instant response time vs long minutes for a plant.
- akjssdk 6y ago
  Battery installations are still relatively expensive right for the capacity they offer right?
  - ZeroGravitas 6y ago
    That's a very general statement, but solar plus lithium battery storage is now competitive with gas peaker plants and those can grid balance as an extra service.

LockAndLol 6y ago

So encasing the cells in glass stopped decomposition? There was no pressure buildup in the cells? No gasses released? The test says it's 1800 hours of stressful conditions for the cells. Assuming 10h of sunlight per day, that's 180 days of stability. I guess time will tell how long they really last, but it's good news that they surpassed test requirements. And having a 25% conversion rate baseline compared to a ~26% assumed max for silicon is also impressive. I wonder how much they can boost that.