Solar cell design with over 50% energy-conversion efficiency

[OKIsItJustMe]

http://www.kobe-u.ac.jp/research_at_kobe_en/NEWS/news/2017_04_21_01.html

[font face=Serif][font size=5]Solar cell design with over 50% energy-conversion efficiency[/font]

April 21, 2017 | Graduate School of Engineering

[font size=3]Solar cells convert the sun’s energy into electricity by converting photons into electrons. A new solar cell design could raise the energy conversion efficiency to over 50% by absorbing the spectral components of longer wavelengths that are usually lost during transmission through the cell. These findings were published on April 6 in the online edition of Nature Communications.

This research was carried out by a team led by Professor KITA Takashi and Project Assistant Professor ASAHI Shigeo at the Kobe University Graduate School of Engineering.

In theory, 30% energy-conversion efficiency is the upper limit for traditional single-junction solar cells, as most of the solar energy that strikes the cell passes through without being absorbed, or becomes heat energy instead. Experiments have been taking place around the world to create various solar cell designs that can lift these limitations on conversion efficiency and reduce the loss of energy. The current world record is at 46% percent for a 4-junction solar cell. If the energy-conversion efficiency of solar cells surpasses 50%, it would have a big impact on the cost of producing electricity.

In order to reduce these large energy losses and raise efficiency, Professor Kita’s research team used two small photons from the energy transmitted through a single-junction solar cell containing a hetero-interface formed from semiconductors with different bandgaps. Using the photons, they developed a new solar cell structure for generating photocurrents. As well as demonstrating theoretical results of up to 63% conversion efficiency, it experimentally achieved up-conversion based on two photons, a mechanism unique to this solar cell. The reduction in energy loss demonstrated by this experiment is over 100 times more effective compared to previous methods that used intermediate bands.

…[/font][/font]

http://dx.doi.org/10.1038/ncomms14962

[NNadir]

1. Gallium arsenide based. There isn't enough gallium on the entire planet to make this useless...

...crap meaningful in any way more than the already useless and worthless and expensive solar scam is right now.

Millions of "breakthrough" announcements have not enabled it to produce 2 of the 574 exajoules we were consuming as of 2015. In fact, the solar industry has never, not once, produced enough energy to keep up with the growth in energy consumption, never mind the replacement of a single exajoule of dangerous fossil fuel consumption.

The idea of distributing arsenic to make distributed energy solar cells that will be landfill in twenty or thirty years is so selfish, so short sighted and so disgusting as to make it an ideal practice for our generation to give to future generations, since we clearly don't give a shit about them and wish to express our contempt as often as is possible.

We'll file this one with the wonderful idea that past generations had of putting lead in gasoline to avoid the problem of having our gasoline engines knock.

There is no limit to the excuses for the tragedy of solar wishful thinking. It's a crime against the future.

[ccarrick]

2. And he's back

The one and only Nnadir, fresh from his uranium-laced foot soak after marching for the climate this weekend, to regale us with logical fallacies and misinformation!

Always great to hear about the dangers of so-called electronic waste. We should really just turn off all the computers and TVs and smart phones and go back to paper and pencils.

And don't bother asking him about nuclear waste, because he won't (really can't) answer that one.

As for the so-called shortage of gallium, why let facts get in the way. http://www.renewableenergyfocus.com/view/3322/indium-and-gallium-long-term-supply/

[NNadir]

3. Um...you know what?

Last edited Mon May 1, 2017, 02:46 PM - Edit history (1)

There are subset of people - not very bright, not very informed and always dogmatic, willing to bet the future of humanity on their stupid, and primitive worship of the sun god - even though, as I point out repeatedly, the world just squandered, between 2005 and 2015 1.111 trillion dollars (Source: GLOBAL TRENDS IN RENEWABLE ENERGY INVESTMENT, 2017 Key Findings, FS UNEP Collaboration Center) on solar energy, with the result that solar, combined with the equally stupid scam, wind energy, and geothermal and tides thrown in, doesn't produce even 2% of the 574 exajoules of energy humanity now generates and consumes each year.

(Source: International Energy Agency, Key Energy Statistics)

Yet, this class of mindless assholes prances on, even more stupid, even more evil, even more indifferent and delusional day after day after day, making mindless and often failed predictions that "by such and such a year" (always after they'll be more than 100 years old) the world will be powered by "100% renewables."

It doesn't matter if they're liars or self deluding fools or scammers for the gas industry, the effect is the same.

Recently in this space,in Trumpian liar doublespeak, that an example of this mindless set announced that knew more than all of the world's scientists and energy experts, and of course, me don't know what we're talking about, but he, of course does:

4. rate of growth in solar is indisputable

and has been consistently underestimated by national energy officials/agencies and solar skeptics like you.

Ditto with the declining cost curve.

So when are you going to stop shilling for nukes, whose costs are NOT going down - despite the over-promises of the government and industry.

All of the criticisms you level against solar promoters goes double for nukes.

Then he went on to announce that I think I'm the smartest guy in the room, while citing a minor official whose publication list largely consists of inventorying the equipment in the NREL laboratories in this classic pot and kettle argument:

You clearly seem to think you're the smartest person in any room, but I'm gonna go with Dr. Mooney and the supercomputer.

Fuck you very much - have a nice life.

There was a time in my life, when I used to confront these stupid little hecklers repeatedly, here and elsewhere.

It's a waste of time though.

These kinds of people are oppressively stupid, ignorant, and indifferent. They think it's a good idea to distribute arsenic because they're dumb enough to think that distributed pollutants are better than concentrated pollutants because they spend all of their time going through the circle jerk of stupid renewable energy websites where the authors are every bit as dumb and illiterate as they are.

They're like Trump voters, inasmuch as no amount of information - for example that the 1.111 trillion dollars squandered on the solar scam in the last decade as mentioned above did nothing to keep the world from surging over 410 ppm this week - will make them admit that they just might be wrong. They're faith based and as such, incapable of exhibiting any flexibility of mind.

I, by contrast, am informed by the primary scientific literature, with which I spend 10 to 20 hours a week. This practice has caused me to change my mind about things, many times. I used to be, many years ago, a dumb fuck anti-nuke "renewables will save us" asshole, for which I apologize to all future generations.

Like I said, to repeat, there was a time in my life, when I used to confront these stupid little hecklers repeatedly, here and elsewhere.

It's a waste of time though.

I now have an "ignore" list, and I use it to prevent myself from wasting time on stupid fucks who are working - as I can clearly see - to destroy the future in prideful ignorance. The "cut and paste" moron is on it, along with the dickhead who thinks that the climate change gas concentration will go down because of "world's largest" solar installations and trivial junk in Maine, the concrete blockhead who giggles stupidly all the time, and, um, the present company.

In my opinion, these dopes are best ignored. They have nothing, absolutely nothing, intelligent or useful to say.

Welcome to my ignore list.

As you say, "Have a nice life."

[kristopher]

4. Well, you would definitely be the inside expert on liars.

No one believes the claptrap you write on solar; but hey, please, keep standing on your metaphorical street corner and screech at everyone about you and 'primary literature'.

Tip - plenty of us read 'primary literature', the difference is that those of us with a genuine commitment to science understand that real science is a philosophical commitment rooted in honestly. Screeds such as you routinely offer up are so transparently dishonest and simpleminded that they scream "anti-science" with every fraudulent sentence.

BTW, how is the marketing going on that basement nuclear reactor you claim to have designed? I mean, what country are you living in now? The last I recall you swore you were going to move out of your elite New Jersey neighborhood and go outside the US to somewhere that demonstrates the proper respect for nuclear power.
Given the economics of the prevailing energy technologies, that must mean that - if you followed through with your threat to emigrate - you've ended up in Russia.

[ccarrick]

5. Pot and kettle

Nnadir likes to call me Trumpian when he is the one who always starts hurling insults and using profanity. And he is the one who is too busy bloviating about how well read he is but continues to use logical fallacies and cherry picking dates and data.

Well listen up smarty pants, the cost of solar and wind has been cut in half or more in the last 5 years so your argument that 1+ trillion has been spent but we've only reached a small fraction of primary energy doesn't mean that that will be the case 10 years from now. And nice of you to try and trick the uninformed by using primary energy which includes liquid fuels for transportation which of course nukes don't address either.

But by all means block me. I will continue to dog you on this site until you hunker down with your spent uranium blankie and take a permanent nap. Maybe in that giant hole the Finns are digging for their nuclear poison - should be done in 100 years or so, give or take a century.

[kristopher]

6. Meanwhile, even as solar and wind are inexorably declining in price

Why nuclear power has no future in California or U.S.

...In 2006, when Toshiba bought Westinghouse for $5.4 billion, the seller projected that by 2020 the global market for nuclear power generation was expected to have grown by 50 percent.

Westinghouse was set to be the king of what Toshiba thought would be the golden age of nuclear power. Toshiba’s president and CEO envisioned a market where 10 large nuclear reactors would be built each year until 2020, amounting to 130 gigawatts of new reactor capacity.

Just 10 years after forecasting billions in profit, Westinghouse’s bankruptcy filing cited as much as $10 billion in debt....

<snip>

“Cost-effective.” Two small words, but a historic end to the perilous age of nuclear power in California.

The agreement to close Diablo Canyon sets to rest the economic question: operating outdated, aging nuclear power plants is more expensive than procuring cheaper, more efficient and cleaner technologies.

http://www.sandiegouniontribune.com/opinion/commentary/sd-utbg-nuclear-industry-demise-20170428-story.html

[ccarrick]

7. The reality-based community

I wish Gov. Cuomo would learn this lesson. We're about to give Exelon $500 million a year for the foreseeable future for these outdated plants in upstate NY.

Of course, nuclear shills like Nnadir will never get it.

But I'm sure he'll come up with his modular nuke design that perfectly reuses spent nuclear fuel any day now.

[OKIsItJustMe]

8. I'm no great fan of nuclear power but...

If those plants are taken off-line, something will be needed to fill the gap. Nuclear is the second largest source of electricity in New York (~ 3.5 GWh)—second only to natural gas (~ 4.0 GWh.) Non-hydro renewable accounts for less than .5 GWh (which, believe it or not, is more than triple the amount generated by coal.)
https://www.eia.gov/state/?sid=NY#tabs-4

Still, if you want to replace those 3.5 GWh with non-hydro renewables, you will need to increase them by a factor of 7-8 overnight.

My guess is that if we shut down those nuclear plants tomorrow, first, old, idle, coal plants would be brought back on-line, then, gas plants would be built to take their place.

Wind and solar will continue to expand in New York, but my first priority is to take the remaining coal and petroleum plants off-line, then the natural gas plants, then after we’ve gotten rid of the fossil fuel plants, the “biomass” burning plants, finally, the nuclear (fission) plants (by the time we’ve eliminated all of the plants which pump carbon into the atmosphere, nuclear fusion may be practical.)

[ccarrick]

9. No blank check for outdated nukes

I generally agree, but the problem is that Cuomo's nuke tax, through the use of Zero Emission Credits (ZECs), is a commitment with no end in sight. For the $500 million a year, we could finally get those offshore wind projects going and build up a supply chain here in New York that would create thousands of jobs. We have GE - let's build on that.

Ditto with storage - we have the Battery Energy Storage Technology (BEST) consortium and a good base of storage companies already here in the state.

And let's finally build the transmission lines down the Hudson Valley to bring in low-cost hydro from Quebec.

[OKIsItJustMe]

10. Well, the offshore wind projects are starting

https://www.nyserda.ny.gov/offshorewind

And we’re expanding solar: https://www.nyserda.ny.gov/All-Programs/Programs/NY-Sun

Now, how long before they can replace 3.5 GWh of nuclear?

I’m all in favor of solar, and (to a lesser extent) wind power, but, it’s going to take time to put it in place, regardless of how much money we throw at it.

[kristopher]

11. As they build more renewables, then what obsolete generation will be turned off?

Nuclear and coal baseload plants are inflexible. As renewable penetration increases. based on lowest cost bidding the market will employ the no-fuel-cost renewables first and the existing fossil fuel/nuclear plants will have to continue splitting a steadily declining market share.

At what point do the inflexible, money-hogging nuclear plants give way? As it stands, the nuclear credits look to be nearly $8B over the next 12 years (and possibly as much as $12B), while only $2.4B is expected for renewables.

Also, you have included some invalid assumptions in your reasoning.

...replace those 3.5 GWh with non-hydro renewables, you will need to increase them by a factor of 7-8 overnight.

Why would we replace the 3.5GWh with non-hydro renewables; and why would that have to take place "overnight"? Both of those assumptions without merit. I'd suggest we look at how the nuclear plants in California have been phased out for a more realistic look at what type of shutdown path would be expected to emerge. And even that is rapidly becoming out-of-date due to the continued rapid price decline of renewable infrastructure.

Where will we be in our carbon replacement effort in 12 years with (A) all the funding going to support nuclear generation that has to be shut down anyway because of it's poor fit to the modern grid; versus (B) putting those funds into sustained strong commitment to renewables and energy efficiency?

ETA one more thought - which of those two pathways will put more pressure on the fossil plants we want to shut down?
There is a well accepted path for new technology adoption called the S-Curve. It basically breaks down the overall path of adoption and replacement into 5 segments (a few details here https://www.democraticunderground.com/1127109684 ).

We are trying to accelerate change and our planning should recognize that we are embarking on the high rate of adoption segment we see in the S curve.

The adoption curve

When an innovation is introduced into a market, it takes a number of year to ‘diffuse’ and penetrate the market. The adoption typically looks like an S-curve as shown in the following chart. The adoption curve provides a useful way to break down customers in five segment: innovators, early adopters, early majority, late majority, laggards.


Adoption curve

Innovators are the first to adopt new products and services. They are technology freaks par excellence, and like experimenting and playing around to find out what they can do with their new toys. Innovators typically represent a few percent of the target user base.

Early adopters also invest early on in new technologies, not as technologists, but to address their concrete problems.

- They typically represent about 10% of the target population.
- In companies, early adopters are opinion influencers. Often they will not be decision makers themselves, but are key to convince others. Early adopters are usually at the centre of extensive communication networks, for instance internal management circles, industry fora, or are very sociable individuals in their private sphere.
- When a critical mass of early adopters has developed, the process of technology diffusion becomes self-sustaining and like a snow-ball effect, it spills over to the early majority. On the other hand, competing and incompatible standards slow down the rate of adoption and the transition from early adopters to the early majority.

more at: http://www.business-planning-for-managers.com/main-courses/marketing-sales/marketing/the-adoption-curve/

[OKIsItJustMe]

12. I'm sorry?

The generation mix in New York has been changing:
http://www.nyiso.com/public/webdocs/media_room/press_releases/2015/Child_PowerTrends_2015/ptrends2015_FINAL.pdf


Wind (& “Other Renewables”) and Natural Gas have increased. Coal and Oil have decreased. Hydro and Nuclear have remained constant.

I want to eliminate electricity generated by burning stuff, in order of most carbon produced.

1. Coal
2. Oil
3. Natural Gas
4. “Biomass”
5. Uranium

[kristopher]

13. How do you suggest we impose that order on a dynamic economic entity?

It's all well and good to take a position that goes straight to the desired goal, but (especially when you're dealing with a massive piece of cultural infrastructure like the energy system) you have to integrate change into the existing economics and technology in a process that doesn't always follow the most obvious path.

So, how do you suggest we impose the sequencing you want on a dynamic economic entity? That's the point my questions are pointing to.

I've received a huge amount of grief here because too few people understand that the key element in this transition away from carbon is shifting from a strategy of least cost power provision oriented to the characteristics of baseload generation to one geared to filling in the cracks left by massive deployment of non-dispatchable renewables.

The bridge idea behind natural gas is that it shuts down the baseload plants and opens opportunity for the widespread deployment of renewables that results in achieving the dramatic price reductions we've been seeing over the past 10 years - reducing carbon emissions in the process.

What natural gas cannot do is compete on cost with ubiquitous solar and wind. As wind and solar technologies very soon become the least cost option everywhere those inexpensive-to-build natural gas plants will have a steadily decreasing role to play as they go from the baseload substitute role to the steadily declining one of dispatchable backstop for solar and wind.

The economic functionality of that process is an essential part of being on the most rapid path to elimination of carbon-e emissions.

Catering to the nuclear industry will ultimately result in more carbon emissions than their early retirement because it skews the economic forces that would otherwise propel the very, very achievable price declines in wind and solar that are required for actually ending carbon dependence.

[NeoGreen]

14. What effect will the...

...decentralization of the current model of power generation to local residential/commercial renewable generation have on the economics of maintaining large electric point-production facilities and their inherent ~50% line loss?

That is to say, will the removal of the bulk of distribution line-loss have a significant positive effect toward the transition to local renewable production? Will the local production be significant enough that our overall net production/consumption of electricity could be reduced through decentralization? If so, should planning for local (decentralized) micro networks and storage be promoted? And if so, how can we leverage that advantage to preferentially target the current production modes that release the most carbon.

On a side note, is carbon the only/best metric? Should we calculate the amount of life cycle methane released by NG and its effect on climate change? Should the costs of Mercury (Hg) and other pollutants (i.e. nuclear wastes) be included in the equation in determining the worst fuels and the rank of the producers of those wastes?

[OKIsItJustMe]

15. Methane is another carbon emission and greenhouse gas, so, yes, it counts

“Other pollutants” (e.g. nuclear wastes) are (of course) a concern. However, right now, we face an existential threat from the atmospheric levels of carbon emissions.

The accumulation of nuclear wastes is a very real problem, however, it does not represent an immediate threat, and, frankly, is a localized threat. There are various schemes to deal with it, but none of them will matter if we are all dead.

https://www.theguardian.com/environment/2015/dec/03/nuclear-power-paves-the-only-viable-path-forward-on-climate-change

…

Nuclear power, particularly next-generation nuclear power with a closed fuel cycle (where spent fuel is reprocessed), is uniquely scalable, and environmentally advantageous. Over the past 50 years, nuclear power stations – by offsetting fossil fuel combustion – have avoided the emission of an estimated 60bn tonnes of carbon dioxide. Nuclear energy can power whole civilisations, and produce waste streams that are trivial compared to the waste produced by fossil fuel combustion. There are technical means to dispose of this small amount of waste safely. However, nuclear does pose unique safety and proliferation concerns that must be addressed with strong and binding international standards and safeguards. Most importantly for climate, nuclear produces no CO₂ during power generation.

…

[kristopher]

24. That is pie-in-the-sky BS from the nuclear lobby.

Fundamental claims about next generation nuclear are not able to be supported when subject to close scrutiny. The same lobbying group making those claims assured us in 2003 that if their wish list of policies were enacted, the world would be building 100 new nuclear plants a year by 2020. Well, they got everything they wanted (and more) in the 2005 energy bill and nuclear is crumbling as a viable energy option.

We KNOW renewables work.

[OKIsItJustMe]

16. Hansen's proposed carbon fee would be a good start

Last edited Wed May 3, 2017, 07:57 PM - Edit history (1)

https://www.scientificamerican.com/article/legendary-climate-scientist-likes-a-gop-proposal-on-global-warming/

…

What’s the United States’ best hope for solving climate change at this point?

The only effective way of addressing climate change is to make the price of fossil fuels include their cost to society. That could be done in a simple way by collecting a fee from the fossil fuel companies that would gradually rise over time—a carbon fee and dividend. Studies show this would benefit the economy and this is a conservative approach, where you let the market move you toward a better situation.

…

What is the number-one action the U.S. could take to reduce its emissions, without the federal government?

Unless you get a fee on carbon, you cannot solve the problem. As long as fossil fuels appear to be cheap energy, they’re going to keep being burned by somebody. So ultimately the solution has got to involve the government.

…

https://www.democraticunderground.com/1127110094

[kristopher]

17. In case you missed the headline - a carbon tax can't be passed

Ignoring reality is a dangerous thing, and policy planning that stops at " If only we could..." is sheer stupidity.

So what is the fallback plan to impose the order of shutdown you listed?

If you don't have one, you might want to consider the position I've outlined that will work. These nuclear plants have done nothing to change the fundamental system that is built around carbon emitting fuels. Now, at a time when every step of expanding renewable infrastructure is a step closer to a complete revamp of our energy system the antirenewable acts to preserve the presence of nuclear plants is more likely to slow down the transition and ultimately result in the production of more GHGe than any other outcome.

[OKIsItJustMe]

18. Sophie Sez #1: You loaded 16 tons, what do you get?

[kristopher]

21. I don't click thru on videos

If you have an actual response to what I took the time to write, please make it

BTW, it isn't Hanson's carbon tax. It has been a long standing policy solution that many, many, many other people have pushed for an extremely long time. It does make perfect sense, but AFAIK there is still zero chance of getting it passed.

[OKIsItJustMe]

22. Too bad... so sad...

Good night!

[kristopher]

23. So you still can't actually engage on a point when it goes against your beliefs?

I saw Joe (You lie!) Walsh act the same way earlier today on health care.

Since you like videos

http://www.msnbc.com/msnbc-news/watch/former-rep-opposes-jimmy-kimmel-s-stance-on-health-care-debate-935707203758

[OKIsItJustMe]

19. Sophie Sez #2: "Obama Missed a Golden Opportunity but We Can Still Win!"

[kristopher]

25. But it hasn't passed, has it?

Those fundamentals in presentations on a carbon tax haven't changed since I first saw them in in 2002...

What do you propose is different now than then?

[OKIsItJustMe]

20. Sophie Sez #3: "$1000 for You A Better World for Your Children"