A method developed by MIT of splitting water molecules mimics the way photosynthesis works in plants. (NEWSCOM)
MIT researchers attain solar ‘nirvana’
By Eoin O'Carroll | 08.01.08
A big drawback of solar power is that it doesn’t work at night or on cloudy days. But researchers at MIT say they now have an inexpensive way to store solar energy when the sun isn’t out.
Daniel Nocera, a chemistry professor at MIT, and Matthew Kanan, a postdoctoral fellow in Mr. Nocera’s lab, have developed a catalyst made from cobalt and phosphate that can split water into oxygen and hydrogen gas. When used in conjunction with a photovoltaic solar panel, their system can use water to store the sun’s energy.
A press release from MIT explains how it works:
The key component in Nocera and Kanan’s new process is a new catalyst that produces oxygen gas from water; another catalyst produces valuable hydrogen gas. The new catalyst consists of cobalt metal, phosphate and an electrode, placed in water. When electricity – whether from a photovoltaic cell, a wind turbine or any other source – runs through the electrode, the cobalt and phosphate form a thin film on the electrode, and oxygen gas is produced.
Combined with another catalyst, such as platinum, that can produce hydrogen gas from water, the system can duplicate the water splitting reaction that occurs during photosynthesis.
At night, the hydrogen and oxygen can be recombined into a fuel cell to produce a carbon-free electric current that can power your home or charge an electric car.
Wired explains why this system represents a breakthrough:
Solar energy currently makes less than one percent of the world’s electricity. The main drawback of the technology, preventing wider adoption, is that solar systems only make power while the sun is shining. At night or on cloudy days, those in need of power must look elsewhere. So storage of electrical energy has been a long-sought after technological advance. Batteries work but they’re too big and expensive. Fuels, fossil or renewable, are different: They act as their own storage, allowing for easy transport and usage. That’s one reason that coal and oil have such a dominant hold on the world’s energy market.
But how much water would it take to power a home? The Guardian suggests that it would be less than a gallon a day:
Converting an Olympic swimming pool of water into hydrogen and oxygen per second would create 43 terawatts of power. “In the next 50 years, the world needs 16 terawatts. By the end of the century, we’ll need around 30,” said Nocera. “There’s a heck of lot of energy stored in chemical bonds.”
For a home, Nocera said that it would be enough to split a few litres of water per day into hydrogen and oxygen. The water would be reformed when the gases were put through the fuel cell.
There is much work to be done in converting Nocera’s idea into a commercial product. At the moment, his catalyst can only accept small amounts of electrical current at once, meaning that it would be an inefficient way to quickly store large amounts of energy. But Nocera is certain that engineers will iron out the issues and produce commercial-scale products within a decade.
Nocera and Kanan are not the first to come up with a way of splitting water molecules to produce hydrogen and oxygen. The process, known as electrolysis, was discovered as early as 1800. But electrolysis has always required expensive machines using exotic metals or nanoparticles, and it has required the water to be pressurized and heated. Nocera and Kanan’s process uses common elements to split room-temperature water.
“This is the nirvana of what we’ve been talking about for years,” said Nocera in the press release. “Solar power has always been a limited, far-off solution. Now we can seriously think about solar power as unlimited and soon.”
Scientists don’t normally talk like this, and Nocera is not alone in his robust claims. The MIT press release quotes James Barber, a biochemist at Imperial College London who was not involved in this research.
“This is a major discovery with enormous implications for the future prosperity of humankind,” he said. “The importance of their discovery cannot be overstated since it opens up the door for developing new technologies for energy production thus reducing our dependence for fossil fuels and addressing the global climate change problem.”
(At this point, it’s hard not to think of the story in the satirical Onion newspaper titled “Amazing New Hyperbolic Chamber Greatest Invention In The History Of Mankind Ever.”)
This is the second time this month that MIT has made headlines with advances in solar technology. Two weeks ago researchers in the university’s engineering school announced that they had developed an inexpensive mixture of organic solar concentrating dyes that can be painted on to windows.
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2. Ralph Ritchie | 08.02.08
Sounds as if the University PR guys are at work. They tend to go overboard.
First, Solar electric systems, just about any solar system, do not work on an on-off basis. I use solar electricity to entirely power my office every night ( night owl ). I use about 3 KWH nightly. In the morning when the sun comes up the system recharges by 10:AM. If it is cloudy or foggy, it may take an extra hour to charge the batteries, but it is ready to work again the next night.
I still have power for my well and a few extras. The system was designed to provide an emergency power source, but since the power was available, I use it all the time.
Second, I can estimate the intensity of a storm by watching the monitored collector current. Even under the heaviest cloud cover, the system still works, but at lower levels.
Three. I have noted a rise in collector current at night when there is a full moon. Tracking doesn’t work at night, so the rise in collector current only shows when the moon passes by the collector position.
This is in the Northwest, where solar electricity isn’t supposed to be “viable”. We also use solar space heating and a solar water heater. We have been using them for over twenty years.
It is described in a two-volume set on this system: “Emergency Power With Solar Electricity.” by Ralph W. Ritchie. The other solar applications are also described in our books.
I will likely try a hydrogen system when it gets past the sensational stage.
3. Lebanese Brother | 08.02.08
My sister’s electrolysis has given her a whole new life. Men no longer shun her. It was not however inexpensive. It’s to bad this new MIT discovery wasn’t around when she needed it. She could have saved some money.
4. MJ DeYoung | 08.02.08
Anything to get us away from dependence on the homicidal middle eastern neanderthals and their dirty oil is welcome! Yaaaaay!!
5. Henry Beck | 08.02.08
all good stuff going on in photovoltaic energy research and development, but it’s too early to celebrate prototypical projects have been trumpeted, such as thin film technology. This topic needs another 5-10 years to mature.
6. Rob Safuto | 08.04.08
Exactly how inexpensive is the process? Platinum is currently trading at over $1600 per oz. I would like to see an estimate of how much the system that the MIT scientists are testing would cost to implement in a home.
7. Steve | 08.04.08
OK… Another “endless” supply of energy to go on destroying the planet with. It’s not just WHERE we get out energy that’s the problem, but what we do with it. Sorry to be your party-******!
Now that we have this solution, let’s not use it like we used oil - as a means to further human conquest and greed.
8. Minhas | 08.05.08
God gave us the biggest nuclear reactor, the sun, yet we are so hooked to the dirty Saudi oil, that this abundant energy resource has been ignored for too long. MIT has done it’s part, we engineers now need to put this technology at our service fast and at affordable cost. Can we do it?
9. Randy Scarlett | 08.05.08
I would like to know If I potilcan put the money in this research like they cailm how much soon can this be deploved into everyday use for the household?
10. martin normanton | 08.05.08
See “electrolysis of water” in wikipedia. the major inefficiency is at the oxygen producing electrode, so the increased efficiency of this system at that electrode is another step on the long road away from fossil fuels and global warming. But note comment 6 about how we use the energy!
11. martin normanton | 08.05.08
While platinum seems to be preferred coating material for the elctrodes, Wikipedia mentions that stainless steel is also usable.
12. Karen | 08.05.08
It sounds like a wonderful idea, however, it will never be brought to the level we need it unless the people in charge of the world see a way to make tons of money from it. Nothing gets developed for commercial use unless some money grubbing creep can find a way to make a fortune off of it. OK so I’m jaded about our economy, but I’m old enough to have seen many great ideas get swept under the carpet just because it was going to take a chunk out of the money the oil and cattle barons were going to make out of the status quo.
13. atticus finch | 08.05.08
the most recent discovery that has not been mentioned, is that they’ve found a way to use goretex instead of platinum.
Also, some people say that once people are able produce our own fuel indavidualy for free, the economy will collapse because people will have so much money, that inflation will run wild. sort of like when the bank lowers interest rates, and then inflation hits the dollar. I dont know if this is true or not. I would like to think that this is not the case, and that it will lead to a more even dispesment of wealth for the worlds poor.
14. MW | 08.05.08
If I remember my chemistry correctly, and I may not, the energy released by breaking the H-O2 bond in water is equal to the energy it takes. Therefore if producing electricity is the goal,you’ve gained nothing. Just use a battery and don’t worry about dealing with the most reactive gas on earth. While the technique may be a major building block, it isn’t an answer.
15. Eoin | 08.05.08
MW, that’s exactly right. Hydrogen and oxygen are not energy sources (unless you want to split their atoms!), they are just energy carriers. That’s why you should never believe anyone who tells you that they have devised something that “runs on water.”
So hydrogen fuel cells behave a lot like batteries, but they are superior in nearly every respect – lighter, potentially cheaper, less toxic, and, importantly, far more efficient on a pound-for-pound basis. That’s why people are so excited about the “hydrogen economy.”
A better question may be why we would need to use solar energy at night. Why not just switch to wind power, which is often stronger at night? This objection, along with many others, was raised in a post by renewable energy guru Jospeh Romm in his blog Climate Progress. Check it out here:
16. Terry | 08.05.08
This technology has been used in the automobile by many inventors. You hear about it and then you hear nothing else. Hopefully now, with the information age, everyone can finally know that we can produce energy from regular water and use it. THIS can solve the energy crisis we have.
As for our dependance on oil, that will never end. For as long as we have petroleum based products out there, we will always need oil. Plastic, styrofoam, Vaseline, tires, etc, etc, etc. In fact, only a small portion of oil actually goes into gas for our vehicles. Gasoline is the byproduct of diesel and home heating fuel.
This energy from water needs to be finally sent out to the masses. We need to shout to our officials, automotive industry leaders and the leaders of home heating units.
17. Eoin | 08.05.08
Terry, I’m all for clean energy, but you there’s no way you can “produce energy from regular water.”
18. Cyril R. | 08.06.08
Eoin, what made you think fuel cells are more efficient than batteries?
The opposite is true. Fuel cells are typically 30-50 percent efficient overall. There’s lots of losses because fuel cells are mechanically complex compared to batteries. Plus entropy is not on hydrogen’s side; the maximum theoretical efficiency of catalysis and recombination are both 83% because there is an entropy loss of one sixth. You cannot get better than this, ever, and in reality, there are compressors and pumps and stuff. So overall theoretical cycle efficiency could be up to one half, which, well, sucks.
19. Cyril R. | 08.06.08
In reality what we’re seeing right now is closer to one third cycle efficiency. I’ve thought for a long time about how to skew this theoretical efficiency limit, but have come to the conclusion that it cannot be done.
20. Stephen Lyons | 08.07.08
Perhaps your readers would be interested in watching a 10-minute video about the Nocera-Kanan discovery. It’s the pilot for a project called Chemical Explorers, a series of Internet videos about interesting developments in modern chemistry. Because it’s intended for a general audience, the video doesn’t go into the kind of technical detail that some of the earlier posts do. But it does allow viewers to hear directly from the two chemists behind this discovery, it shows the cobalt catalyst in action, and it tells the interesting story of how the discovery came about. The video can be watched at the following site:
http://chemicalexplorers.blip.tv/#1150780
Steve Lyons
21. clickitysplit | 08.07.08
The idea is during the day, some of the electricity coming off your panels goes to refilling your H and O tanks. At night, the H and O are recombined to power your home while the resulting water is put back into the system to be split the next day.
Like wind, which isn’t consistently available at night in all geographies, coastal and rainy climates may not get enough sun to keep the system running with the sort of regularity we’ve have come to expect from the grid.
It remains to be seen just how inexpensively these systems can be marketed and how restrictive local building codes might get. Would they be as expensive as new solar or air conditioning systems in the average home? Will tanks have to go outdoors or even underground?
I don’t see this possible breakthrough as a panacaea, but if it could work for you it would be a great way to stick it to the local power company.
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1. mark | 08.01.08
It sounds like electrolysis. Where are the numbers? X% cheaper, Y% greater
yeild than existing methods… An MIT breakthrough(?) should include this.