Breaking the barriers for low-cost energy storage

Aug 01, 2012

A team of researchers has developed a cheap, rechargeable and eco-friendly battery that could be used to store energy at solar power plants for a rainy day.

Led by Sri Narayan, professor of chemistry at the USC Dornsife College of Letters, Arts and Sciences, the team developed an air-breathing battery that uses the generated by the oxidation of iron plates that are exposed to the in the air – a process similar to rusting.

"Iron is cheap and air is free," Narayan said. "It's the future." Details about the battery will be published July 20 in the Journal of the Electrochemical Society.

As currently developed, Narayan's batteries have the capacity to store between eight and 24 hours' worth of . His patent is pending, and both the federal government and California utilities have expressed interest in the project.

Iron-air batteries have been around for decades – they saw a surge in interest during the 1970s energy crisis, but suffered from a crippling problem: a competing chemical reaction of hydrogen generation that takes place inside the battery (known as hydrolysis) sucked away about 50 percent of the battery's energy, making it too inefficient to be useful.

Narayan and his team managed to reduce the energy loss down to 4 percent – making iron-air batteries that are about 10 times more efficient than their predecessors. The team did it by adding very small amount of bismuth sulfide into the battery. Bismuth (which happens to be part of the active ingredient in Pepto-Bismol and helps give the pink remedy its name) shuts down the wasteful hydrogen generation.

Adding lead or mercury might also have worked to improve the battery's efficiency, but wouldn't have been as safe, Narayan said.

"A very small amount of bismuth sulfide doesn't compromise on the promise of an eco-friendly battery that we started with," he said.

Narayan's team included fellow USC researchers G. K. Surya Prakash, Aswin Manohar, Souradip Malkhandi, Bo Yang, Robert Aniszfeld, Chenguang Yang, Phong Trinh; and Andrew Kindler of NASA's Jet Propulsion Laboratory.

The California Renewable Energy Resources Act, signed into law by Gov. Jerry Brown in April 2011, mandates that the state's utilities must generate 33 percent of their power from renewable energy sources by the end of 2020.

This aggressive push toward renewable energy sources presents utilities with a problem: solar power works great on clear days and wind power is wonderful on windy days, but what can they do when it's cloudy and calm out? People still need electricity, and won't wait for the clouds to clear to turn the lights on.

Currently, solar and wind power make up a relatively small part of the energy used in California. In 2009, 11.6 percent of electricity in the state was generated by wind, solar, geothermal, biomass and small hydroelectric plants combined. (Large hydroelectric plants accounted for an additional 9.2 percent.) As such, dips in energy generation from solar and wind power plants can be covered by the more predictable coal-burning grid.

As California moves toward more , solar- and plants will need an effective way of storing large amounts of energy for use during clouding and calm days.

Traditionally, utilities store power by pumping water uphill into reservoirs, which can then release the water downhill to spin electricity-generating turbines as needed. This method is not always practical or even feasible in drought-ridden California, where water resources are already in high demand and open reservoirs can suffer significant losses due to evaporation, Narayan said.

Batteries have typically not been a viable solution for utilities. Regular sealed batteries, like the AAs in your TV remote, are not rechargeable. Lithium-ion batteries used in cell phones and laptops, which are rechargeable, are at least 10 times as expensive as iron-air batteries.

Despite his success, Narayan's work is still ongoing. His team is working to make the battery store more energy with less material.

Explore further: Matched 'hybrid' systems may hold key to wider use of renewable energy

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User comments : 37

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indio007
1 / 5 (3) Aug 01, 2012
Store energy it as a compressed gas or liquid. Problem solved.
antonima
5 / 5 (5) Aug 01, 2012
Compressors are inefficient and so are the generators that harness the stored energy. Also the compressors themselves would have to be enormous to be of industrial use. Its not that simple!
dnatwork
5 / 5 (1) Aug 01, 2012
It is that simple. It just doesn't work.
Newbeak
5 / 5 (1) Aug 01, 2012
Here's the ticket: http://www.techno...battery/
NotParker
1.8 / 5 (10) Aug 01, 2012
"solar power works great on clear days and wind power is wonderful on windy days, but what can they do when it's cloudy and calm out? People still need electricity, and won't wait for the clouds to clear to turn the lights on."

Wow. Imagine how much many trillions could have been saved if people had admitted that sooner.
Newbeak
3.2 / 5 (5) Aug 01, 2012
I wonder how much power could be stored if you dug a 500 foot deep pit,and lifted a 1000 ton weight with excess juice.When needed,the weight could be allowed to sink,turning a generator.
Vendicar_Decarian
3.4 / 5 (5) Aug 01, 2012
Liquids are practically incompresible.

Gases are compressible but compression induced heating and the need to heat the resulting liquid to turn it back to a gas dramatically reduces the efficiency of compressed gas as a energy storage media.

"Store energy it as a compressed gas or liquid. Problem solved." - Indio

Learn some physics.
kochevnik
3 / 5 (4) Aug 01, 2012
Store energy it as a compressed gas or liquid. Problem solved.
Much of the compressed energy dissipates as hot air cools to ambient temperatures.
Wow. Imagine how much many trillions could have been saved if people had admitted that sooner.
Yes. Trillions of amoebas!
Vendicar_Decarian
2.6 / 5 (5) Aug 01, 2012
Why wonder? The answer is $0 trillions.

"Imagine how much many trillions could have been saved if people had admitted that sooner." - ParkerTard

Poor mentally diseased ParkerTard.
NotParker
Aug 01, 2012
This comment has been removed by a moderator.
Eoprime
1 / 5 (1) Aug 02, 2012
I wonder how much power could be stored if you dug a 500 foot deep pit,and lifted a 1000 ton weight with excess juice.When needed,the weight could be allowed to sink,turning a generator.


You could use SI units and do the math in your head... you know there IS an advantage to use them.

1 metric ton @ 500foot

152,4m*9,81m/s²*1000 = .... J

subtract some percent for efficiency of the generator, friction loss ect.
hemitite
2.3 / 5 (3) Aug 02, 2012
How about reversing the current to turn some of those wind generators into giant fans to blow the clouds away? ;)
antialias_physorg
5 / 5 (6) Aug 02, 2012
Imagine how much many trillions could have been saved if people had admitted that sooner.

It is only you who never read past page one on any subject that has missed the point that EVERY alternative energy plan EVER conceived has ALWAYS stressed the need for an energy buffer in addition to the powerplant. Greens have NEVER said otherwise. Scientists have NEVER said otherwise. People investing in wind/solar have NEVER said otherwise.
You have only chosen to read what you want and be wilfully blind to the rest (and then accuse others of being blind - which was funny to watch because the only blind person was/is you)

You kept harping on about it as if it was something only you had realized. Guess what - you were the LAST person to realize it.
Feldagast
5 / 5 (2) Aug 02, 2012
Imagine how much many trillions could have been saved if people had admitted that sooner.

It is only you who never read past page one on any subject that has missed the point that EVERY alternative energy plan EVER conceived has ALWAYS stressed the need for an energy buffer in addition to the powerplant. Greens have NEVER said otherwise. Scientists have NEVER said otherwise. People investing in wind/solar have NEVER said otherwise.
You have only chosen to read what you want and be wilfully blind to the rest (and then accuse others of being blind - which was funny to watch because the only blind person was/is you)

You kept harping on about it as if it was something only you had realized. Guess what - you were the LAST person to realize it.

If it was known that STORAGE was needed for it to work properly, why have they spent all the time and money in building all of them already? Was it a gamble that something would appear to make it all better? It didn't help solyndra
Vendicar_Decarian
5 / 5 (2) Aug 02, 2012
Anonymous sources tell me that ParkerTard is also the last person to realize that he has soiled his underpants, when he soils his underpants.

"Guess what - you were the LAST person to realize it." - Antialias.
NotParker
1 / 5 (5) Aug 02, 2012

If it was known that STORAGE was needed for it to work properly, why have they spent all the time and money in building all of them already? Was it a gamble that something would appear to make it all better?


Exactly. R & D is one thing. Manufacturing the grotesquely expensive useless crap in China and exporting all that subsidized money is another.
Vendicar_Decarian
3.7 / 5 (3) Aug 02, 2012
Solyndra tried to compete against China, and China shut them down hard.

The American response - forced by Republicans - has been to cut and run from the industry.

China is now in full control.

"Manufacturing the grotesquely expensive useless crap in China and exporting all that subsidized money is another." = ParkerTard

TrinityComplex
not rated yet Aug 02, 2012
Whether you agree with the alternative energies that have been put into place or not, at least some of them have managed to work, otherwise they would not still be in used and expanding. Many rely on weather, which most people agree is not ideal, but that's the reason for various technologies. Hopefully there will be options that come out to harness natural energies that don't depend on the weather, but until then the search continues. Even huge proponents of 'green' energy admit that there are drawbacks an no one option has proven a complete solution, but living and having lived near coal power plants I can tell you that I definitely prefer a myriad of cleaner options to the one nasty power producer near where I live. I'm even willing to pay a few cents more per KWH if it means the air is less brown.

The search continues, and here's another step along the way.
NotParker
1 / 5 (5) Aug 02, 2012
Solyndra tried to compete against China, and China shut them down hard.

The American response - forced by Republicans - has been to cut and run from the industry.

China is now in full control.

"Manufacturing the grotesquely expensive useless crap in China and exporting all that subsidized money is another." = ParkerTard



Only idiots manufacture products at a massive loss just to collect subsidies from poor people. Democrats = idiots.
Vendicar_Decarian
4.7 / 5 (3) Aug 02, 2012
Those Chinese must certainly be idiots then, with their sustained 9 percent economic growth rate, trillions in cash, and much of America now in their pockets.

"Only idiots manufacture products at a massive loss just to collect subsidies from poor people." - ParkerTard

Money Grubbers like ParkerTard just don't have the brainpower to comprehend how markets can and are captured at the expense of a little short term loss.

To them, a dime in their pocket today is worth more than a trillion dollar market tomorrow.

It is one of the reasons why Conservative/Libertarian economics has proven itself to be a perpetual failure.

It has gotten to the point now where China is now so economically powerful that it can throw America into a grand depression with a flick of it's wrist.

Americans can thank Republican/Libertarian economic ideology for that situation.

http://www.youtub...PI6no5ng
Howhot
5 / 5 (2) Aug 03, 2012
It is one of the reasons why Conservative/Libertarian economics has proven itself to be a perpetual failure.


Yeap. That has been my experience too.
NotParker
1 / 5 (4) Aug 03, 2012
Those Chinese must certainly be idiots then, with their sustained 9 percent economic growth rate, trillions in cash, and much of America now in their pockets.

"Only idiots manufacture products at a massive loss just to collect subsidies from poor people."


"Take a look at Suntech Power Holdings Co., a Chinese firm that bills itself as the worlds largest manufacturer of solar panels. The company lost over $1 billion last year on revenue of $3.2 billion;"

If you get state subsidies to kill off all other countries solar panel manufacturing, you can continue to throw away billions.

Solar panels = massive losses.
Vendicar_Decarian
5 / 5 (2) Aug 04, 2012
Yup, they were willing to lose a billion to put Solyndra out of business.

Now they own the market.

And America is in the enviable position of having lost another industry.

Well Done ParkerTard

Who is the financial backer of Suntech power?

The Chinese government of course. Keeping it going with interest paid by Americans on the debt they owe to China.

Snicker.

http://blogs.wsj....bsidies/
Vendicar_Decarian
5 / 5 (2) Aug 04, 2012
China is playing to win.

ParkerTard can't even figure out the rules of the game.
Eikka
3 / 5 (2) Aug 04, 2012
1 metric ton @ 500foot

152,4m*9,81m/s²*1000 = .... J


One kWh being 3.6 MJ, the answer comes out as 0.4 kWh.

Energy storage by gravity is quite ineffective.
NotParker
1 / 5 (3) Aug 04, 2012
China is playing to win.


Of course. But a winning strategy for the USA would have been to subsidize R&D instead of subsidizing the manufacturing of inefficient panels at a massive loss. Now China can buy up the patents cheap and in 100-200 years when solar power is cheaper than shale gas (and a miracle occurs) manufacturing could start.
Newbeak
not rated yet Aug 04, 2012
Liquids are practically incompresible.

Gases are compressible but compression induced heating and the need to heat the resulting liquid to turn it back to a gas dramatically reduces the efficiency of compressed gas as a energy storage media.

"Store energy it as a compressed gas or liquid. Problem solved." - Indio

Learn some physics.

Not so sure.Check this idea out: http://ucs.berkel...rgystor/
Sonhouse
not rated yet Aug 05, 2012
1 metric ton @ 500foot

152,4m*9,81m/s*1000 = .... J


One kWh being 3.6 MJ, the answer comes out as 0.4 kWh.

Energy storage by gravity is quite ineffective.


But all you need to do is build a billion of them and you have 400 gigawatt hours of storage:)
indio007
2.3 / 5 (3) Aug 05, 2012
I don't care what people that lack imagination say. No other method of energy storage will work indefinitely. All leak energy.
Storing the energy in pressure vessel stores the energy for a VERY LONG time. The same can not be said for other methods. Whats the efficiency of pressure storage compared to a battery after 10 years on a single charge?

It's so crazy it just might work.

I think these guys need a physics lesson too.
Bewia
1 / 5 (2) Aug 05, 2012
The cheap but heavy battery may not represent the "low-cost energy storage" for non-stationary applications, like the electromobiles. In particular, in city transportation the automobiles accelerate and decelerate often, and the energy dissipated in this way will account to the total cost of energy storage. The high inner resistance of battery would increase this cost because of ohmic losses. In addition, the low life-time of battery (low number of charge-discharge cycles) would participate to the total cost of energy storage as well. In brief, the price of battery material is only one factor between many others. We should realize, the technologies like the cold fusion would make the energy storage unnecessary and they should be therefore researched with higher priority, than the technologies of energy storage.
indio007
3 / 5 (2) Aug 05, 2012
http://hydrostor....hnology/

http://palestineh...y-center

more fools with no knowledge of physics I guess.
antialias_physorg
5 / 5 (3) Aug 05, 2012
But all you need to do is build a billion of them and you have 400 gigawatt hours of storage

Or 1-2 big ones.
There's a proposal on the table over here to saw two 1km diameter granite blocks (1km high) out of a mountain and pump water underneath. These could be made to rise about 500m. It is estimated that this would be enough for all of germany as a storage solution for when we go 100% renewables. One of these could store 1.7TWh of power

(There's already people bidding for the place on top to build a house there. The view would be spectacular)

The nice thing is: no new technology needs to be created for this.

I'm usually not so much in favor of mega-engineering. But THAT I'd really like to see put into practice.
roboferret
not rated yet Aug 06, 2012
NotParker
1 / 5 (3) Aug 06, 2012
But all you need to do is build a billion of them and you have 400 gigawatt hours of storage

Or 1-2 big ones.
There's a proposal on the table over here to saw two 1km diameter granite blocks (1km high) out of a mountain and pump water underneath. These could be made to rise about 500m. It is estimated that this would be enough for all of germany as a storage solution for when we go 100% renewables.


I thought Germany was building 23 new coal power plants.

Shale gas would be cheaper and cleaner than building more coal power plants.
antialias_physorg
5 / 5 (2) Aug 06, 2012
What has building coal power plants got to do with storage solutions?

We're not at 100% renewables yet - far from it.
There needs to be some intermediate solution (and yes: these include gas and coal, even though they are polluting types of powerplants. There's no such thing as a golden way to full renewables in one day).
But never fear: those powerplants will also go the way of the Dodo in time. Maybe we'll keep them around for the few windless/sunless days accross the globe.

Shale gas would be cheaper and cleaner than building more coal power plants.

Whether shale gas is better than coal is in doubt. But the simple fact is that we have coal but not shale gas - so for the time being that one is really a non-issue.
Eikka
not rated yet Aug 09, 2012
It is estimated that this would be enough for all of germany as a storage solution for when we go 100% renewables. One of these could store 1.7TWh of power


Energy.

And that estimate is completely misguided because Germany consumes about 4000 TWh a year in various forms, and if you intend to fill all energy demand with renewables (no gas, oil, coal, nuclear), that amount of storage represents approximately three hours worth of energy.

Counting the yearly electricity demand alone (~500 TWh), it represents just one day worth of backup power. Or a 10% deficit/surplus in production for 10 days.

Furthermore, contrasting to that number; renewables like wind power have differences as much as 30% between summer and winter months, much more with solar power, which means you actually need dozens and dozens of these moving mountains to make do with fluctuating energy production because you need to store months of energy, not days or hours.
Eikka
not rated yet Aug 09, 2012
Besides, lifting a kilometer wide stone plug a kilometer high still requires about a cubic kilometer of water to fill the cylinder, which is a pretty big lake if you lay it flat 10 meters deep.

So along with a mountain, you need a body of water as well, that you can fill and empty at will, which is exactly the same problem as with the pumped dam reservoirs - it only replaces the upper reservoir with a stone plug.
Feldagast
not rated yet Aug 18, 2012
and i can see that not holding pressure well or indefinately.

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