March 06, 2006
Metal-Organic Frameworks Advance In Hydrogen Energy Storage
Has GM been pursuing hydrogen as a Machiavellian intrigue to delay a shift to a better technology? I've never believed that. But some people have made this argument in the comments sections of previous posts. Well, suppose that hydrogen vehicles turn out to work and General Motors puts them into production (see below). Paranoid conspiracists then could always argue that the success was an accident and that the plotters thought that scientists wouldn't so quickly come up with workable solutions. Conspiracy theorising can pretty much explain away any evidence and make it fit a conspiracy theory. Chemists have achieved sufficient density of hydrogen in a storage material for transportation needs but their method still requires a very low temperature.
Chemists at UCLA and the University of Michigan report an advance toward the goal of cars that run on hydrogen rather than gasoline. While the U.S. Department of Energy estimates that practical hydrogen fuel will require concentrations of at least 6.5 percent, the chemists have achieved concentrations of 7.5 percent — nearly three times as much as has been reported previously — but at a very low temperature (77 degrees Kelvin).
The research, scheduled to be published in late March in the Journal of the American Chemical Society, could lead to a hydrogen fuel that powers not only cars, but laptop computers, cellular phones, digital cameras and other electronic devices as well.
"We have a class of materials in which we can change the components nearly at will," said Omar Yaghi, UCLA professor of chemistry, who conducted the research with colleagues at the University of Michigan. "There is no other class of materials where one can do that. The exciting discovery we are reporting is that, using a new material, we have identified a clear path for how to get above seven percent of the material's weight in hydrogen."
The materials, which Yaghi invented in the early 1990s, are called metal-organic frameworks (MOFs), pronounced "moffs," which are like scaffolds made of linked rods — a structure that maximizes the surface area. MOFs, which have been described as crystal sponges, have pores, openings on the nanoscale in which Yaghi and his colleagues can store gases that are usually difficult to store and transport. MOFs can be made highly porous to increase their storage capacity; one gram of a MOF has the surface area of a football field! Yaghi's laboratory has made more than 500 MOFs, with a variety of properties and structures.
Yaghi sounds optimistic about solving the temperature problem using his metal-organic frameworks (MOFs) approach. He also does not see cost as an obstacle.
"We have achieved 7.5 percent hydrogen; we want to achieve this percent at ambient temperatures," said Yaghi, a member of the California NanoSystems Institute. "We can store significantly more hydrogen with the MOF material than without the MOF."
MOFs can be made from low-cost ingredients, such as zinc oxide — a common ingredient in sunscreen — and terephthalate, which is found in plastic soda bottles.
"MOFs will have many applications. Molecules can go in and out of them unobstructed. We can make polymers inside the pores with well-defined and predictable properties. There is no limit to what structures we can get, and thus no limit to the applications."
In the push to develop hydrogen fuel cells to power cars, cell phones and other devices, one of the biggest challenges has been finding ways to store large amounts of hydrogen at the right temperatures and pressures. Yaghi and his colleagues have now demonstrated the ability to store large amounts of hydrogen at the right pressure; in addition, Yaghi has ideas about how to modify the rod-like components to store hydrogen at ambient temperatures (0–45°C).
"A decade ago, people thought methane would be impossible to store; that problem has been largely solved by our MOF materials. Hydrogen is a little more challenging than methane, but I am optimistic."
In a separate story "Seicmic" points me to an announcement by General Motors that they expect to start selling hydrogen cars in 4 to 9 years. (same article here)
General Motors Corp has made major steps in developing a commercially viable hydrogen-powered vehicle and expects to get the emission-free cars into dealerships in the next four to nine years, a spokesman told Agence France-Presse.
GM also expects it will be able to 'equal or better gas engines in terms of cost, durability and performance' once it is able to ramp up volume to at least 500,000 vehicles a year, spokesman Scott Fosgard said.
Hydrogen storage containers, like batteries, are just a way to store energy. The cheapest way to make hydrogen currently is from fossil fuels. But a workable way to store hydrogen at room temperature would, like better batteries, make it a lot easier to end the dependence of cars on oil. Advances in solar, wind, and nuclear power will eventually lower their costs far enough to make them cheaper sources of energy for producing hydrogen. Also, a cost effective hydrogen storage technology, just like cheaper batteries, would allow solar wind to supply a larger fraction of all used energy because the ability to store energy helps any energy source that is not continuously available.
We still also need a big acceleration of research and development on both photovoltaics and nuclear reactor designs. We need cheaper non-fossil fuels energy sources. The storage problems are not going to be what prevents the transition away from fossil fuels. Higher costs of alternatives remain the biggest obstacle to phasing out fossil fuels.
If one assumes that GM is not run by idiots (I know it is a debatable point among some) they may consider themselves in possession of some solutions to the problems that described in this post. Only time will tell of course. A couple of comments/question:
What would be the estimated range of a viable fuel cell? How does this compare to gas and/or batteries?
Is not a Hydrogen car same as an electric car in that they both use electric motors for propulsion - but have different sources for electricity (fuel cell vs battery)
Would a viable fuel cell battery bring back (to some extent at least) the old prop planes which could use them to spin the prop?
"Has GM been pursuing hydrogen as a Machiavellian intrigue"
You are kidding of course. They couldn't intrigue their way to lunch at McDonald's.
"he chemists have achieved concentrations of 7.5 percent ... at a very low temperature (77 degrees Kelvin)."
That is the temperature of liquid nitrogen. I'll bet that you would be better off using liquid nitrogen to power your car, than to have to electrolyize water and then cool the hydrogen to that temperature.
"an announcement by General Motors that they expect to start selling hydrogen cars in 4 to 9 years"
GM will be dead and gone in less than 4 years.
The problem with Hydrogen is that it has too many obstacles that have yet to be addressed:
1. low density of hydrogen: this can be addressed via beter storage media and liquiefaction but this only option only takes you so far before you exploit all potential.
2. hydrogen leakage: the hydrogen molecule is too small such that it permiates through alot of materials. Imagine putting gas in your car only to find the tank half full the next morning.
3. Lack of infrastructure and very expensive cost of erection: to my understanding building gas stations for any form of gas is prohibitively expensive. A CNG(natural gas) station costs around $ 2 million each while a conventional gasoline station may cost as little as $ 30,000 each. By the time these multi million dollar stations are constructed - if invetors are willing to take risk- the technology may have run out of steam.
4. There may be other more vialble options of reducing pollution or producing "zero emmission" car operation. These options eg use of biomass derived fuels or fuels like Ethanol and biodiesel are currenlty cheaper than hydrogen, compatible with current infrastructure and albeit not totally emission free reduce net CO2 produced significantly. NOTE: that use of htrogen derived from fossil fuels is nothing but a false promise since it may actually emit more pollutants than use of those fuels directly.
5. Will a hydrogen economy provide energy security, clean environment affordable cars and fuels all at the same time? Most likely not.
Finally, this technology seems like one for the day after the day after tommorrow. Fuel cells can run on other cheaper fuels are already in production. A good example is the Direct Methanol Fuel Cell. Methanol fuel is cheap at around $ 1/ gallon wholesale and can be made from a widerange of feed stock including CO2 reforming, natural gas, coal, biomass, MSW, RDF.
heheheheh! "GM will be dead in 4 years." That cracked me up. GM just sold its stake in Suzuki a few days ago; Suzuki is one of the next promising Japanese car companies. It sold its stake in Subaru a few months ago. All this money is going to clean up US "legacy costs" mess. GM looks like British Rover which shed assets gradually an still ended up in the grave. I think car companies like FORD, GM will end up outsourcing entire car producion to companies that can make better cars at a lower cost without hiring 500, 000 employees.
LOWERING TEMPERATURE TO MAKE GAS PORTABLE.
This is just like Natural gas even though NG consumes less energy to handle. It takes alot of energy to induce gas transportability to a point that it might not make economic or enviromental sense; the energy used in the process could have instead been for propulsion.
I'm sure GM has been pursuing whatever they were getting paid to pursue at the moment, plus it has a lot of internal resistance to change (e.g. hybrids threaten the automatic transmission interests). This explains why we're seeing baby steps like the belt alternator starter from GM; they threaten no interests within the company at the cost of any other. This does indicate that nobody with technical vision is looking out for the company as a whole, which is why it will (and deserves to) go bankrupt.
They are conspiring to require a very low temperature! ;)
Well, unfortunately, I agree with Don Lancaster on hydrogen.
It ain't happening and unless we build a hell-of-a-lot of nuclear reactors, it won't be cost-effective.
I am surprised that people aren't talking about the carbon fuel cell. http://www.netl.doe.gov/publications/proceedings/03/dcfcw/BNL%20steinberg.pdf Currenly almost all hydrogen is derived from steam reforming of methane where the carbon ends up as CO2. With concentrated solar energy (or other high temp sources), the methane can be pyrolized to hydrogen and solid carbon black. With the very high efficiency of the carbon fuel cell and solid carbon black, I would bet that the energy density would be far higher than a similar fuel tank of hydrogen, however you store it. For the purists (luv ya gmoke), the methane could be sourced from biofuels and/or the pure CO2 exhaust could be absorbed by amines and transferred to your greenhouse later to fertilize the growth of your organic garden. It would be a bit of a challenge to scale down the carbon fuel cell for transportation because it is a high temperature device, but that is a lot less of an engineering challenge than ramping up dangerous and expensive new-gen nuke plants to create hydrogen. Besides, think of the recycling potential: eat a good meal, take a crap, put it in the digester, pyrolize your methane, drive to the grocery store, grow you own food, eat a good meal, take a crap...
Besides, think of the recycling potential: eat a good meal, take a crap, put it in the digester, pyrolize your methane, drive to the grocery store, grow you own food, eat a good meal, take a crap...
You have just invented the perpetual motion machine.
PS: I bet you can get more mileage out of a White Castle burger than a Big Mac.
"Has GM been pursuing hydrogen as a Machiavellian intrigue to delay a shift to a better technology?"
I wouldn’t put it quite that way. First, I don’t think they see hybrids as better: they’re in denial, and a very narrow, traditional engineering economy analysis of cost-benefit can be used to justify that. I think E-P put it well, when he pointed out that various component groups in GM aren’t happy about electrics or hybrids. Each group doesn’t add up the big picture, and admit to themselves that they’re blocking “a better technology”. They just know that it’s new, and it would be bad for them, so it’s gotta be a bad idea.
Second, they’re desperately hoping for lower gas prices. They know that if gas prices go higher, and SUV sales fall further, that they’ll have to go bankrupt. They dodged a bullet in the 90's with low gas prices and high SUV sales, and they’re praying that they can do it again. They saw hydrogen as the least costly sop to pressure groups and public opinion, and they got the cooperation of the Bush administration in making hydrogen the national goal. Sounds a bit conspiratorial, but it’s garden variety industry influence over government.
For a sample of what others are saying, see this BBC article:
"Professor Blythe, who is one of the key contributors to the government future transport strategy, claimed it was the manufacturers who were dragging their feet.
"We have had a lot of meetings with car companies, who promote their green credentials - but they say we are not going to do much for the next 20 to 30 years because our customers don't want to pay more."
BBC Article Link
I am surprised that people aren't talking about the carbon fuel cell.
Some of us are talking about it.
Uh, kerosene and diesel fuel will still be vastly superior long after all the fossil fuel is gone. Synthesize it from limestone and water with extra power and it'll still get you where you want when you need high volumetric energy density. Its still the best way to store hydrogen.
Fuel cells I have no faith in for the next thirty years at least; Diesel engines are a hell of a lot cheaper and nearly as efficient.
Anyone who thinks that we're not talking about DCFC's isn't paying attention.
Getting back to GM, the management has to remember how they killed the ZEV mandate in California (with some help from the ideologues in California, pushing unworkable demands). GM probably sees peak oil as another political battle. This error will cost them their jobs, and I hope it costs them their severance contracts.
I agree with Dezakin for the most part - diesel, gasoline, etc. is a remarkably efficient (by volume and by weight) way to store hydrogen in a convenient room temperature liquid stored and transported by existing infrastructure and the carbon atom chains that act as a carrier for the hydrogen are themselves easily converted to a gaseous oxide.
good luck beating it in the forseeable future.
Paul D & E-P,
Talking is good. I would sure like to help to commercialize the technology, perhaps by investing in the companies moving forward. I am researching that and will let you know what I find. If you have some information along those lines please let us know.
There is lots of value in any storage system. Even at low density, storing solar power as hydrogen allows solar power in remote locationa, as either wind or sun. The stored hydrogen could be formed into diesel or methane for more convenient transport use.
Also, storage means home power generation can be saved for when it's needed, and will encourage enterpreneurs to improve on it. Improved storage encourages the moarket for the power source, so the cost of the alternative power will drop. Even if the power cost is the currently prohibitve factor, more storage options provides incentive to chase improvements in alternative power.
There is lots of value in any storage system. Even at low density, storing solar power as hydrogen allows solar power in remote locationa,
There are other chemical energy storage systems that could be superior.
For example, the manganese oxide cycle:
- MnO2 --> MnO + 1/2 O2 (at T > 1080 K)
- MnO + 1/2 O2 --> MnO2 (in a fuel cell)
Manganese is cheap and available in teraton quantities, if needed.
The first reaction would occur in a solar concentrator; the MnO remains solid so it can be separated from the oxygen before cooling. There's also a hydrogen-splitting cycle that exploits this reaction, followed by reaction of the MnO with sodium hydroxide and then with water.
Why not work to eliminate the need for cars as much as possible? Technology workers can basically work from anywhere the internet allows and do not need to travel for the most part. Today there are conference devices for voice and video to handle most meetings alleviating the need to go to an office. If our communities allow walking, cycling or use of the public transit cars become an unnecessary liability. As a former urbanite from NYC I know people can do very well without cars. Public Policy toward reducing or eliminating the need for cars would help keep us healthy. I realize it is a radical idea but how about a nation without traffic jams and grid lock as our future? If we consider the cost to every car owner of their vehicle purchase, loan fees, registration, maintenance, gas...etc and then taxes we all pay for roads it becomes clear the never ending auto oriented economy will become undesirable and unsustainable. The difficulty of changing fundamentals in our culture given the billions spent over decades on advertisement to help us make up our mind as to how we will live in an endless suburban sprawl are many. Just think about sustainable communities without SUV's? There is a place called "the villages in Florida" where golf carts are becoming the norm so maybe we can change how we live and breathe.