Cheaper solar cells with 20.2 percent efficiency

January 18, 2016
3-D illustration of FDT molecules on a surface of perovskite crystals. Credit: Credit: Sven M. HeinCopyright: EPFL

EPFL scientists have developed a solar-panel material that can cut down on photovoltaic costs while achieving competitive power-conversion efficiency of 20.2%.

Some of the most promising today use light-harvesting films made from perovskites - a group of that share a characteristic molecular structure. However, perovskite-based solar cells use expensive "hole-transporting" materials, whose function is to move the positive charges that are generated when light hits the perovskite film. Publishing in Nature Energy, EPFL scientists have now engineered a considerably cheaper hole-transporting material that costs only a fifth of existing ones while keeping the of the solar cell above 20%.

As the quality of perovskite films increases, researchers are seeking other ways of improving the overall performance of solar cells. Inadvertently, this search targets the other key element of a solar panel, the hole-transporting layer, and specifically, the materials that make them up. There are currently only two hole-transporting materials available for perovskite-based solar cells. Both types are quite costly to synthesize, adding to the overall expense of the solar cell.

To address this problem, a team of researchers led by Mohammad Nazeeruddin at EPFL developed a molecularly engineered hole-transporting material, called FDT, that can bring costs down while keeping efficiency up to competitive levels. Tests showed that the efficiency of FDT rose to 20.2% - higher than the other two, more expensive alternatives. And because FDT can be easily modified, it acts as a blueprint for an entire generation of new low-cost hole-transporting materials.

"The best performing perovskite solar cells use hole transporting materials, which are difficult to make and purify, and are prohibitively expensive, costing over €300 per gram preventing market penetration," says Nazeeruddin. "By comparison, FDT is easy to synthesize and purify, and its cost is estimated to be a fifth of that for existing materials - while matching, and even surpassing their performance."

Explore further: Perovskite solar cells become even more promising with cheaper materials

More information: Saliba M, Orlandi S, Matsui T, Aghazada S, Cavazzini M, Correa-Baena J-P, Gao P, Scopelliti R, Mosconi E, Dahmen KH, De Angelis F, Abate A, Hagfeldt A, Pozzi G, Graetzel M, Nazeeruddin MK. A molecularly engineered hole-transporting material for e cient perovskite solar cells. Nature Energy 15017, 18 January 2016. DOI: 10.1038/NENERGY.2015.17

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Sonhouse
5 / 5 (7) Jan 18, 2016
They still have to solve that pesky moisture degradation issue. Solve that and they will have something.
gkam
2.4 / 5 (10) Jan 18, 2016
With the progress we see on all fronts, we should be able to make great progress in the transition to cleaner fuels. The real chapter will be written by photovoltaic building materials.
cgsperling
2.7 / 5 (7) Jan 18, 2016
I see articles weekly about new, better solar tech, but nothing ever seems to get fielded.
gkam
2.7 / 5 (12) Jan 18, 2016
cg, it takes time to perfect them, to find the best ways to produce them, to actually build the machines to make them, and put it all together, find routes for sales and and engineer the entire system for deployment.
kochevnik
4.2 / 5 (5) Jan 18, 2016
Panel cost is not the major element. People waste $66K on stupid plastic computerized cages with wheels. The problem is people who do not or will not be good stewards of their environment because they have lazy habits
betterexists
1.4 / 5 (11) Jan 18, 2016
Funny: Why All of this?
Make Humans like gigantic trees, Planted in Soil with Root hairs....of course, DEVOID OF ANY BRAIN inside the Skull!
Just make sure no Animals or Pests come & attack for their food.
betterexists
1 / 5 (9) Jan 18, 2016
Funny: Why All of this?
Make Humans like gigantic trees, Planted in Soil with Root hairs....of course, DEVOID OF ANY BRAIN inside the Skull!
Just make sure no Animals or Pests come & attack for their food.

First see whether you can successfully stick an earthworm or scorpion into soil, of course removing its brain first!
When? Next Century? Next Millennium?
greenonions
4.7 / 5 (12) Jan 18, 2016
Considering that solar has fallen by around 16% per year for the past 3 years - http://a.disquscdn.com/uploads/mediaembed/images/3062/3882/original.jpg

And utility solar fell by 17% in just the 3rd quarter of 2015 - http://cleantechn...q3-2015/

We live in interesting times.
Whydening Gyre
5 / 5 (9) Jan 19, 2016
Man, I think ol' betterexists is gettin' worse...
antialias_physorg
4.6 / 5 (11) Jan 19, 2016
Man, I think ol' betterexists is gettin' worse...

Yeah...now he's already talking to himself...and that in a some garbled form of language only he can understand (if that)
Lord_jag
4.5 / 5 (8) Jan 21, 2016
Standard solar is already 1/3rd the price of Nuclear, 1/2 the price of NG. and a small fraction of the cost of a new coal fired power plant.

The only reason we keep using these other solutions is that whole sunk cost thing. We already have coal, NG and nuclear plants. Until they need to be replaced they are cheaper to operate than to buy solar.

But just a simple refit of a nuclear power plant costs more than replacing it with solar.

We need to install 36% solar power right now. Then lets discuss storage.
WillieWard
1.7 / 5 (6) Jan 21, 2016
a small fraction of the cost of a new coal fired power plant.
ironically backed by coal-fired powerplant to compensate intermittency.
CO2 tonnes per capita(2011-2015): France= 5.2, Germany= 8.9
http://data.world....CO2E.PC
http://carboncoun...burning/
http://carboncoun...easible/
We need to install 36% solar power right now.
Luckless natural landscapes.
gkam
1.6 / 5 (7) Jan 21, 2016
Let's remove the liability waiver we essentially gave this disastrous technology. Let them pay for the damage they cause, instead of the governments.
gkam
2.1 / 5 (7) Jan 21, 2016
Ooops, I was discussing the role of nukes in opposition to the use of PV. If we get rid of Price-Anderson and its derivatives, we can get rid of nuclear power.

The first paragraph disappeared.
greenonions
3.9 / 5 (7) Jan 21, 2016
ironically backed by coal-fired powerplant to compensate intermittency.


Or hydro, or a nuke, or gas turbine, or battery storage, etc. etc. Willie is such a one dimensional thinker. Staggering that Willie wants to comment on a science site. Main point is that every Kwh generated by non carbon source - keeps C02 and pollutants out of the atmosphere. Willie does not care about the millions dying of respiratory conditions. http://www.who.in...tion/en/ Progress will happen - despite the luddites.
WillieWard
2.3 / 5 (6) Jan 21, 2016
does not care about the millions dying of respiratory conditions. http://www.who.in...tion/en/
CO2 tonnes per capita(2011-2015): France= 5.2, Germany= 8.9
http://data.world....CO2E.PC
http://carboncoun...burning/
http://carboncoun...easible/
"The story seems to reinforce the fact that every time you vote against nuclear power you are voting in favor of fossil fuels, and this is true even in a country aggressively committed to renewables."
http://blogs.scie...dy-bear/
http://www.theepo...ty-coal/
WillieWard
2.3 / 5 (6) Jan 21, 2016
Main point is that every Kwh generated by non carbon source - keeps C02 and pollutants out of the atmosphere.
"we can't achieve our clean-energy goals by relying heavily on solar and wind because they are intermittent energy sources that require backup power from fossil fuels on days when the weather isn't cooperating."
"to solve the world's biggest environmental problem say that nuclear power is the best approach to reducing greenhouse-gas emissions."
"In fact, it's a key part of the answer to climate change."
http://www.columb...20f.html
gkam
2.5 / 5 (8) Jan 21, 2016
"ironically backed by coal-fired powerplant to compensate intermittency."
------------------------------------

That is a funny way to tell us how alternative energy is the first choice, and has relegated coal to backup.

Every kWh produced by alternative energy is one not produced by polluting sources.
kochevnik
4.2 / 5 (5) Jan 21, 2016
@WillieMentalWard "The story seems to reinforce the fact that every time you vote against nuclear power you are voting in favor of fossil fuels, and this is true even in a country aggressively committed to renewables."
I am using solar which is not nuclear or fossil, but fusion
WillieWard
2.2 / 5 (6) Jan 21, 2016
I am using solar which is not nuclear or fossil, but fusion
Ironically fossil-fuel energy came from solar energy, as fossil fuel is a kind of "fossilized biofuel", and the biofuel energy came from the photosynthesis process supplied by solar energy, or nuclear fusion energy from the Sun. Geothermal energy is from Earth's core radioactive decay, also nuclear. Thereby nuclear is the real/fundamental source of energy.
Solar is nuclear.
gkam
2.1 / 5 (7) Jan 21, 2016
It may not be too late to stop the Vogtle plants, but folk have to understand how much they will wind up paying for those nuclear turkeys. And the terrible costs will go on as long as they are allowed to gouge their customers, . . . and are planning for operating and billing for fifty years.

If the owners decide to abandon and not pay the billions of dollars we foolishly insured, they can do it. After all, they can buy PV and wind for about 3-4 cents, and have no operating personnel to worry about, nor maintenance on powerplants, nor fuel cost changes, nor toxic waste troubles.

Operatives like Willie, but for real, did a number on us through our politicians. Let's make them buy power at the rates from these powerplants.
greenonions
4.2 / 5 (5) Jan 21, 2016
From Willie's own article
This is not to suggest that we should lessen our commitment to renewable energy sources.


Ever wonder why Willie will never answer the question "what is the cost of electricity from a nuke?" I can answer that well from wind and solar. http://cleantechn...-future/
http://cleantechn...us30mwh/
Think you can come close to that Willie? Let's see your numbers.
greenonions
4.3 / 5 (6) Jan 21, 2016
Willie
The story seems to reinforce the fact that every time you vote against nuclear power you are voting in favor of fossil fuels, and this is true even in a country aggressively committed to renewables.
And to support your lie - you once again trot out your blog from Scientific American. You have done this before - and I have pointed out that the information in this article is flat wrong. Germany does NOT import electricity from France - it EXPORTS energy to France. I have shown you this over and over. Here is the facts - http://energytran...r-power/ Damn you are frustrating Willie - keep telling the same lies over and over.
WillieWard
1.8 / 5 (5) Jan 22, 2016
wind/solar provokes grid instability due to intermittency. Wind of change is now in favor of nuclear power.
"a massive injection of solar power of the scale envisaged may perturb grid stability. Solar farms, unlike coal and nuclear power plants, cannot deliver the same amount of continuous electricity."
"renewed interest in nuclear energy in advanced economies like the US, France and Germany provides an important signal of its viability and safety."
"large ground-mounted solar PV farms require space for other accessories, the total land required for a 1 MW of solar PV power plant would be around 4 acres. So investment in solar power must provide for a mammoth hidden cost. "
http://www.livemi...ype.html
http://www.pri.or...es-again
https://www.clean...ansition
antialias_physorg
3.9 / 5 (11) Jan 22, 2016
wind/solar provokes grid instability due to intermittency.

It does? Really? You know all the power outages we are NOT having in germany (as, say, opposed to the US)?
http://energytran...r-years/

Power redistributions have increased but that is a relative term. They are still very rare and easily handled.
And this is without using any other measures which are still possible (e.g. shifting usage times for major industry consumers) which is still a possibility.

Add to that that the big powerlines that will redress any problems aren't even built yet (being built as we type) AND that the first storage facilities are also just now coming on line
http://cleantechn...largest/

So I think between these four measures we are well covered to have an as stable grid as we enjoy currently.
gkam
2.1 / 5 (7) Jan 22, 2016
anti, WillieWard is really BillBoard.

You are arguing with a sign.
WillieWard
1.8 / 5 (5) Jan 22, 2016
PV and wind for about 3-4 cents
"The hidden costs of wind, solar power"
"billions of dollars for large buildings storing millions of batteries that contain toxic, flammable, and explosive materials"
"While costs for solar and wind projects have decreased over the last decade thanks in part to heavy taxpayer subsidies, their costs remain significantly higher than traditional natural gas or coal-fired power plants. Sunshine and wind are free, but the technology needed to collect that energy is very expensive."
"Then there is the simple and undeniable fact that solar and wind generation is just plain inefficient and what we call in the industry, intermittent. Solar only functions when the sun is shining, and is heavily diminished when the weather is cloudy. Wind generation only works when the wind is blowing."
https://www.wind-...mentary/
http://energymag....d-solar/
greenonions
4.4 / 5 (7) Jan 22, 2016
Solar only functions when the sun is shining, and is heavily diminished when the weather is cloudy. Wind generation only works when the wind is blowing.

No???? We had no idea. Oh my god Willie - stop the presses. You had better get in touch with the engineers who are building the turbines. They thought the turbines worked when the wind was not blowing. This will be such a shock. They thought that solar panels worked 24/7 too. This is going to change everything.....
kochevnik
3.4 / 5 (5) Jan 22, 2016
Solar only functions when the sun is shining, and is heavily diminished when the weather is cloudy.
Amorphous cells work very well in ambient light of cloudy weather. Moreover Victron charge controllers are designed for cloudy weather of the Netherlands. So you are wrong again

As for efficency and cost, the power line loss and transformer heating is about 50%. Also you must factor in the $1trillion USA spends yearly securing foreign energy to dynofuels

Ironically fossil-fuel energy came from solar energy, as fossil fuel is a kind of "fossilized biofuel"
Irrelevant. Solar power is direct fusion power, whereas fossil efficiency is something less than one trillionth
Lord_jag
4.4 / 5 (7) Jan 22, 2016
That 36% number wasn't just plucked out of the air.
http://phys.org/n...ent.html

It turns out you need about 36% solar before you start having an effect on baseload.

You see we use more power during the day. It just so happens that daytime is when solar panels work best......

So every watt solar panels make is one less watt that must be made by peak-on-demand power plants. The most expensive and dirtiest kind.

After 36% sure... some of your complaints start becoming valid. Lets get to 36% and then address your complaints about expanding further.
Eikka
3.7 / 5 (3) Jan 24, 2016
But just a simple refit of a nuclear power plant costs more than replacing it with solar.


How do you "replace" a near 24/7 power source with something that comes online for about four hours a day and often doesn't work at all?

It turns out you need about 36% solar before you start having an effect on baseload.


That's 36% of peak demand - on a summer day - not total year-round generation and demand. Apples to oranges, and false generalizations.
Eikka
3 / 5 (4) Jan 24, 2016
So every watt solar panels make is one less watt that must be made by peak-on-demand power plants. The most expensive and dirtiest kind.


That's not quite true. The dirties kind are the ones that have to change output the fastest, because they're the least efficient of the bunch.

Solar power first decreases the need of these types of powerplants - in the summer when the peak load coincides with the peak solar output - but as the amount is increased the opposite happens because baseload generation has to be replaced with these fast load following plants in order to accomodate this rapid mid-day dip in baseload generation.

In the winter it becomes a different matter entirely because the peak load shifts towards the evening with people turning lights and heaters on, so the problem gets worse. You get a dip and then a peak.

The whole question is not so cut and dry as some sloganeering gkam would like to make it out.
Eikka
3 / 5 (4) Jan 24, 2016
Amorphous cells work very well in ambient light of cloudy weather. Moreover Victron charge controllers are designed for cloudy weather of the Netherlands. So you are wrong again


No charge controller can get around physics: when there's a cloud in front of the sun, the panel output drops dramatically.

The lighting levels on an overcast day are around 1,000 lux whereas a clear sky is about 100,000 lux. The actual physical amount of direct and indirect light reaching the solar panel diminishes by a factor of 10-100 depending on the cloud coverage, and no charge controller can help that.

When you get 10% of the light into the panel, how do you make any more than 10% the electricity?

As for efficency and cost, the power line loss and transformer heating is about 50%.


Buuuuullshit. The average transmission loss in the US grid is about 5-7%
greenonions
5 / 5 (2) Jan 24, 2016
Eikka
The whole question is not so cut and dry as some sloganeering gkam would like to make it out
Correct. Or as cut and dried as some coward hiding under a desk who hates progress would like to make out. Fact is that the engineering of energy is incredibly complex. Different power sources, different loads on a day by day basis, constantly changing costs for fuel sources etc. etc. One thing is very clear - it will benefit our world to transition from fossil fuels - to cleaner alternatives. Go ask Beijing, or Mumbai if you don't agree with that. You can also look at some aerial pictures of Canadian forests being destroyed, or google oil pipeline spills. Innovation has brought the cost of solar power down to grid parity - and the costs are going to keep falling. Time will tell - but it looks as if solar will become the dominant energy source as we go forward - which is the point of this article. You can stay under the desk Eikka.
gkam
1.7 / 5 (6) Jan 24, 2016
I did not say it would be easy, I said it would be both possible and profitable and a great improvement for society. But you take the obvious problems and assume it kills the technology.

We are very aware of the problems involved, but you are just coming to the game, uneducated, but as a reader of the science. But you do not get all of it by reading, as we have seen before.

Your eagerness for argumentation often exceeds your technical experience.

My PV panels finally go up this week. But then again, I also served in the military and other acts of citizenship, so it is no surprise I am carrying my own weight here as well.
Osiris1
not rated yet Jan 24, 2016
This appears next to an article about our need to stop burning stuff...coal...oil...trash...peat...manure...etc.; and START using renewables like our photo voltaics.

Curious this article is right next to that on. One identifies the problem, and this the solution. Lets get working! Nuclear is in the mix too. We do not have to dispose of hi level waste on planet...send it into deep space. We have the rockets now cuz' Bezos and Musk have shown us the way.
kochevnik
not rated yet Jan 25, 2016
@eIKKA No charge controller can get around physics: when there's a cloud in front of the sun, the panel output drops dramatically.

The lighting levels on an overcast day are around 1,000 lux whereas a clear sky is about 100,000 lux. The actual physical amount of direct and indirect light reaching the solar panel diminishes by a factor of 10-100 depending on the cloud coverage, and no charge controller can help that.
You are measuring planar waves, which are almost abscent on cloudy days. Instead the light is randomly phased ambient. Amorphous panels have 30-50% of efficiency compared to planar waves of full direct sunlight

@Eikka The average transmission loss in the US grid is about 5-7%
You failed to account for loss in the heat->electric conversion

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