
Next-generation solar cells pass strict international tests - headalgorithm
https://www.sydney.edu.au/news-opinion/news/2020/05/22/perovskite-solar-cells-pass-strict-international-tests.html
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jsingleton
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-c...](https://rameznaam.com/2020/05/14/solars-future-is-
insanely-cheap-2020/)

> 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
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
Battery installations are still relatively expensive right for the capacity
they offer right?

~~~
ZeroGravitas
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.

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henearkr
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
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.

~~~
iamthemonster
I'm probably much less well-informed than you, but I can't understand the
arguments about the disposal of the panels at the end of their life. I throw
away a wheelie-bin worth of trash every single week, that's 1040 wheelie bins
over a 20-year panel lifetime, yet those panels are probably equivalent to
about two wheelie bins. It's a microscopic volume. What is in solar panels
that is such a disaster compared to household trash? In 20 years I also expect
to go through ten phones and five computers (although admittedly I'd chuck
them into the local electronics recycling bin).

~~~
nimish
Heavy metals in thin film, mostly. Cadmium isn't great. They can be highly
recycled though. Nevertheless, if a storm destroys a bunch of panels lots of
cadmium will be dispersed

~~~
henearkr
Cadmium telluride is not the prefered technology for solar cells. Silicon is
still the major player, and it is free of any pollutants. I checked the
wikipedia page for "solar cell". Given these informations, any consumer or
technologist can adopt solar without compromising on pollutants.

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kitotik
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?

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ResearchAtPlay
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%.

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einpoklum
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.

~~~
BiteCode_dev
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.

~~~
einpoklum
I didn't suggest fossil-fuel-based energy production is superior.

Having said that - maintenance of cars using fossil fuels is not a relevant
comparison, since we're talking about power plants.

Personally, I doubt that we can just -whoosh- swap the coal and petroleum for
solar-based electricity and have our problems solved. It's likely that a lot
of social effort to conserve more and waste less energy will be necessary to
reach some sort of long-term-sustainable state of affairs.

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LockAndLol
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.

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kumarski
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.

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darksaints
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.

~~~
philipkglass
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
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?

~~~
mkl
If your goal is to power the car while driving, even 100% efficient solar
cells wouldn't be enough, as there simply isn't enough surface area to gather
enough energy to power a normal car doing normal driving. If your goal is to
leave the car sitting charging in the sun all day, that's a bit more
practical, but I believe there aren't yet any production vehicles like that
yet:
[https://en.wikipedia.org/wiki/Solar_car](https://en.wikipedia.org/wiki/Solar_car)

~~~
hnick
Solar trees could help for the parking, but I don't know how the economics of
that plays out.

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econcon
Last time I was installing panels, panel were fairly cheap.

More expensive were inverter, controller, batteries.

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

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

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Fielddisturb
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.

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roenxi
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.

~~~
yardie
When we kitted our boat with solar panels the cheapest part of the entire
system were the panels, ~$1/W. Half of the budget went into mounting and the
fabrication of the mounting hardware and 1/3, or the remainder, went to wiring
and controllers. This nearly lines up with domestic solar. 1/3 to panles, 1/3
to frames and mounting, and 1/3 towards electrical.

Panels at 2% efficiency would be wildly uneconomical at practical any price.

~~~
roenxi
> Panels at 2% efficiency would be wildly uneconomical at practical any price.

I guarantee that is wrong, if the price got low enough it would be economical.
Wikipedia suggests to me [0] plants operate at 3-6%, and plants are extremely
economical. Even starving African children can afford access to plants. If
solar panels were as cheap and easy to produce/distribute as plants but could
be plugged in to a grid then 2% efficiency would be wildly economical - it
would be the greatest energy revolution in human history.

[0]
[https://en.wikipedia.org/wiki/Photosynthetic_efficiency](https://en.wikipedia.org/wiki/Photosynthetic_efficiency)

~~~
anoncareer0212
Lots to unpack here - is there a more straightforward way to word your
argument here? To put GP's post in terms of yours, the planters and water cost
much more than the plant, so even if "starving kids in Africa can afford
access to plants", it doesn't mean greenhouses are free

~~~
roenxi
It isn't an analogy. Plants are literal solar systems. The only reasons they
can't be plugged into the grid is they deal with energy chemically instead of
electrically.

It doesn't require that much imagination to say that solar cells might one day
be work in an extremely similar fashion to plants. Not likely, but not an
outrageous thought.

Nature has produced a cheaper, more ubiquitous and more self-replicating solar
system using efficiencies in the 5% range with a theoretical cap of 11%. That
suggests we don't need 25% efficiency to accomplish amazing things. It isn't a
critical metric.

~~~
perl4ever
I'm fine with your equation of plants with solar power. But it's not cheaper;
look at the price of biofuels. Aren't they in fact more expensive than fossil
fuels and solar panels?

~~~
robotbikes
I think most biofuel is currently more expensive because it is diverting high
input monoculture crops that are typically grown for feed like say corn
ethanol or soybean oil. I believe ethanol from sugar cane in Brazil was cheap
but only because the humans laboring to harvest it and process it were paid
very little. But yeah the current choice of using industrially farmed high
input crops to source biofuel does make it expensive. I think ultimately
heavily refined energy dense fuel does require lots of time or energy input to
produce.

