Solar Cell Efficiency Rises By 30% Through Singlet Fission

[ScienceRocks]

Solar Cell Efficiency Rises By 30% Through Singlet Fission

Solar Cell Efficiency Rises By 30% Through Singlet Fission | CleanTechnica

Scientists were pretty excited when they discovered you could convert light energy directly into electricity by capturing photons in semiconductors, exciting them into “excitons” (bound electron with negative charge and hole with positive), and capturing the resultant current through electrodes. Now a group of four chemists from the University of California, Riverside, has worked out a way for one photon to generate a pair of excited states rather than just one.

It’s called “singlet fission,” and by using it, we should be able to boost solar cell efficiency by as much as 30%, providing “Third Generation” solar power. The Journal of Physical Chemistry Letters published the research results in an Editor’s Choice perspective article last month.

Christopher Bardeen, the chemistry professor whose lab led the research, explains what sent him along this line of inquiry:

Our research got its launch about ten years ago when we started thinking about solar energy and what new types of photophysics this might require. Global warming concerns and energy security have made solar energy conversion an important subject from society’s point of view. More efficient solar cells would lead to wider use of this clean energy source.

“If a triplet exciton has half the energy of a singlet, then it is possible for one singlet exciton, generated by one photon, to split into two triplet excitons,” Dr. Bardeen explains. “Thus, you could have a 200% yield of excitons—and hopefully, electrons—per absorbed photon.”

“The exact mechanism is unknown, but it does happen quickly—at the sub-nanosecond timescale—and with high efficiency,” Bardeen says. His lab’s work has shown that it is very sensitive to molecular alignment and position.

Bardeen cites recent work at MIT that has already demonstrated an organic photovoltaic cell with more than 100% external quantum efficiency based on this effect. Bardeen believes we can use this effect to raise the efficiency of inorganic semiconductors.

Next steps: finding new materials that exhibit singlet fission, figuring out how to turn the triplet excitons into photocurrent efficiently, and determine how the spin properties of the electrons affect exciton dynamics.

 

[Mr. H.]

Now THIS is the shit that Christians should be investing in. Not that nasty fossil fuel.

 

[Mr. H.]

Hey Matty- this is interesting...

MIT creates graphite solar sponge that converts sunlight into steam with 85% efficiency | ExtremeTech

MIT is reporting that it has created a new, cheap material — using a microwave, no less — that converts sunlight into steam with an amazing 85% efficiency. This could have major repercussions in the realms of desalination and sterilization, and perhaps for concentrated solar thermal power generation as well.

 

[Mr. H.]

[MENTION=22889]Matthew[/MENTION]

 

[ScienceRocks]

Great advancement. This is why I post in support of science funding so much!

 

[Mr. H.]

Great advancement. This is why I post in support of science funding so much!

Science? What's that?

 

[whitehall]

You just gotta have faith and it will happen. Today's environmental true believers make fundamental Christians look like amateurs.

 

[ScienceRocks]

You just gotta have faith and it will happen. Today's environmental true believers make fundamental Christians look like amateurs.

Tens of thousands of scientists, billions of dollars and a lot of hard work is how it is done. Not something a losertrian would understand!

 

[Mr. H.]

You just gotta have faith and it will happen. Today's environmental true believers make fundamental Christians look like amateurs.

Tens of thousands of scientists, billions of dollars and a lot of hard work is how it is done. Not something a losertrian would understand!

I hate to keep harping on this, but it's just me...

The oil and gas industries are saturated with scientists, engineers, chemists, geophysicists, geologists, etc... and nearly a trillion dollars is invested year over year...

Yet- who are the biggest opponents of oil and gas? Liberals. The same Liberals who profess to embrace "science" and the same Liberals who claim that Conservatives don't believe in Science and Education. The same Liberals whose goal is to "educate" the world on the absolute necessity to replace hydrocarbons with renewables and sustainables. The same Liberals who insist that it can and will be done.

Horse shit.

 

[idb]

You just gotta have faith and it will happen. Today's environmental true believers make fundamental Christians look like amateurs.

Tens of thousands of scientists, billions of dollars and a lot of hard work is how it is done. Not something a losertrian would understand!

I hate to keep harping on this, but it's just me...

The oil and gas industries are saturated with scientists, engineers, chemists, geophysicists, geologists, etc... and nearly a trillion dollars is invested year over year...

Yet- who are the biggest opponents of oil and gas? Liberals. The same Liberals who profess to embrace "science" and the same Liberals who claim that Conservatives don't believe in Science and Education. The same Liberals whose goal is to "educate" the world on the absolute necessity to replace hydrocarbons with renewables and sustainables. The same Liberals who insist that it can and will be done.

Horse shit.

Ergo....there should be no scientists working in the hydrocarbons industry!

Your logic is impeccable.

 

[Mr. H.]

Tens of thousands of scientists, billions of dollars and a lot of hard work is how it is done. Not something a losertrian would understand!

I hate to keep harping on this, but it's just me...

The oil and gas industries are saturated with scientists, engineers, chemists, geophysicists, geologists, etc... and nearly a trillion dollars is invested year over year...

Yet- who are the biggest opponents of oil and gas? Liberals. The same Liberals who profess to embrace "science" and the same Liberals who claim that Conservatives don't believe in Science and Education. The same Liberals whose goal is to "educate" the world on the absolute necessity to replace hydrocarbons with renewables and sustainables. The same Liberals who insist that it can and will be done.

Horse shit.

Ergo....there should be no scientists working in the hydrocarbons industry!

Your logic is impeccable.

Why didn't I think of that. Pure genius.

 

[ScienceRocks]

When did I say I oppose hydrocarbons? I support renewables as they're forever and a good backup.

 

[RGR]

When did I say I oppose hydrocarbons? I support renewables as they're forever and a good backup.

Forever is a big word. Let us know how well "forever" works once the sun runs low on hydrogen…

 

[idb]

When did I say I oppose hydrocarbons? I support renewables as they're forever and a good backup.

Forever is a big word. Let us know how well "forever" works once the sun runs low on hydrogen…

Good point!
If we build too many solar panels, they'll suck more and more energy out of the sun and it'll run out faster!
Eek!

 

[RGR]

When did I say I oppose hydrocarbons? I support renewables as they're forever and a good backup.

Forever is a big word. Let us know how well "forever" works once the sun runs low on hydrogen…

Good point!
If we build too many solar panels, they'll suck more and more energy out of the sun and it'll run out faster!
Eek!

I don't even think Matthew is dumb enough to fall for that one.

I have this beef with people wildly using the word "sustainable" when what it REALLY means is "this system should continue to work within the time frame I have assigned to it"...ergo the problem with hydrogen on the sun.

There will come a time when the planet will be destroyed, because the solar system itself is not "sustainable". A cockroach and a 5# pag of sugar is perfectly sustainable in a much short time frame, but BOTH are dependent upon the time frames involved.

Sustainability is nothing but an illusion of time. Try convincing the zealots of that one, when all they want to see is THEIR timeframe.

 

[JiggsCasey]

Forever is a big word. Let us know how well "forever" works once the sun runs low on hydrogen…

Good point!
If we build too many solar panels, they'll suck more and more energy out of the sun and it'll run out faster!
Eek!

I don't even think Matthew is dumb enough to fall for that one.

I have this beef with people wildly using the word "sustainable" when what it REALLY means is "this system should continue to work within the time frame I have assigned to it"...ergo the problem with hydrogen on the sun.

There will come a time when the planet will be destroyed, because the solar system itself is not "sustainable". A cockroach and a 5# pag of sugar is perfectly sustainable in a much short time frame, but BOTH are dependent upon the time frames involved.

Sustainability is nothing but an illusion of time. Try convincing the zealots of that one, when all they want to see is THEIR timeframe.

My gawd, you are so chalk full of pretentious pseudo intellectual gobbledygook, it's no wonder you're such a sales advocate for a front-loaded, unsustainable industry.

The time frame isn't a million years out, genius. It's this century for climate, and this decade for economic reboot.

You have a lot of baseless optimism for adapting to supply constraints. Unfortunately, you appear allergic to the question of cost - mainly because, from the start, you don't understand the macro economics involved. Instead, you create straw men and repeat tired, baseless personal insinuation.

I especially love your arrogant sentiment in another thread whereby you blame Californians for choosing to live in California. Because surely they should all be able to just jump in their Lexus SUV and make their vacation home in Montana a permanent residence. Sure thing, Dipshit. Tell us more how every American has the opportunities that you do. I can just hear your arrogant asshattery during Katrina, when those dumb people in New Orleans should have "known better."

Dick.

You're the classic growth-addicted, free market conservative turd. Zero empathy, zero acceptance of physical limits, zero basis in reality.

 

[waltky]

Pebble-fed nuclear reactor offers power and safety...

A Path for Nuclear Power
March-April 2014 > A novel but tested technology, the pebble-bed reactor, can make fission energy safe.

Electric power is like good health: When you have it, you don’t think about it. When you don’t have it, that’s all you think about. Certainly modern civilization isn’t going anywhere without power. Nuclear energy supplies a larger share of that power than many people realize. At present, about 20 percent of the electricity in the United States is generated by 104 nuclear power plants across the country, making it the leading nation in total installed nuclear capacity. There are now 440 reactors in operation around the world, providing about 14 percent of the overall electricity supply. France leads in nuclear use, which provides about 80 percent of the country’s electrical power. China, presently at 2 percent, has 30 or more new plants under construction.

In recent years, political opposition and high costs have halted or even reversed the use of nuclear power, however. The first plant in the United States—the Shippingport Atomic Station, located on the Ohio River 25 miles from Pittsburgh—went online in 1957. Many more started up in the next two decades, but until a few years ago, no new nuclear plants had been licensed here since the 1970s. The commercial nuclear power plants now in operation were generally designed to have a 40-year life span. With new construction largely at a standstill, many plants are being granted 20-year license extensions by the U.S. Nuclear Regulatory Commission.

Now the risks of climate change are prompting utilities and federal officials to take another look at nuclear. According to the Department of Energy’s Energy Information Administration, 37 percent of the electricity in the United States was produced by coal-fired plants, which release high levels of carbon dioxide. Natural gas, which yields about half as much carbon dioxide as coal per unit of energy generated, accounted for another 30 percent. There are only two major zero-carbon components in the United States energy mix. Nuclear supplies 19 percent. And all renewables—including hydroelectric, wind, and solar—collectively account for 16 percent.

The Southern Company has begun construction of two new nuclear units at the Vogtle site, where another two are already operating, on the Savannah River near Augusta, Georgia. They are the first new domestic fission-power plants in more than three decades. But a broader turnaround is unlikely unless nuclear engineers can address two major issues: safety fears (which were compounded by the Fukushima nuclear accident) and high construction and licensing costs. A tested technology, known as the pebble bed nuclear reactor, has the potential to solve both problems—and to make nuclear power a growing part of the carbon-free energy mix worldwide.

Energy Economics 101