Uni claims H2 breakthrough
Hydrogen can fuel the future
 BMW Hydrogen 7: heavy and slow no more? |
Have hydrogen-powered cars that don't pollute the environment moved a step closer? That's the remarkable claim by Bath University following a new discovery that promises to solve the main problem holding back the technology.
Hydrogen is thought to be an ideal fuel for vehicles, producing only water on combustion, but its widespread use has been limited by the lack of a safe, efficient system for onboard storage.
Scientists have experimented with ways of storing hydrogen by locking the gas into metal lattices, but metal hydrides only work at temperatures above 300°C and metal organic framework materials only work at liquid nitrogen temperatures (-198°C).
Now scientists at the University of Bath have invented a material which stores and releases hydrogen at room temperature, at the flick of a switch, and promises to help make hydrogen power a viable clean technology for the future.
Although its fuel to weight ratio is insufficient to make an entire hydrogen tank from it, the material could be used in combination with metal hydride sources to store and release energy instantaneously whilst the main tank reaches sufficient temperature, 300°C, to work.
The team hopes to have the fully-working prototype ready within two to three years.
“The problem of how to store hydrogen has been a major bottleneck in the development of the hydrogen power technology,” said Dr Andrew Weller from the Department of Chemistry at the University of Bath (UK).
“Hydrogen has a low density and it only condenses into liquid form at -252°C so it is difficult to use conventional storage systems such as high-pressure gas containers which would need steel walls at least three inches thick, making them too heavy and too large for cars.
“The US Department of the Energy has said that it wants six per cent of the weight of hydrogen storage systems to be hydrogen in order to give new hydrogen powered cars the same kind of mileage per tank of fuel as petrol-based systems.
“While metal hydrides and metal organic framework materials can achieve this kind of ratio, they only work at extremes of temperature which are difficult to engineer into an ordinary vehicle.
“Our new material works at room temperature and at atmospheric pressure at the flick of a switch. Because it is made from a heavy metal (rhodium), its weight to fuel ratio is low, 0.1 per cent, but it could certainly fill the time lag between a driver putting their foot on the accelerator and a metal hydride fuel tank getting up to temperature.
“We are really very excited about the potential this technology offers.”
The University of Bath researchers made the discovery whilst investigating the effect that hydrogen has on metals. Having constructed an organo-metallic compound containing six rhodium (a type of metal that is also currently found in catalytic converters in cars) atoms and 12 hydrogen atoms, they began studying the chemical properties of the complex with researchers in Oxford (UK) and Victoria (Canada).
They soon realised that the material would absorb two molecules of hydrogen at room temperature and atmospheric pressure – and would release the molecules when a small electric current was applied to the material.
This kind of take up and release at the atomic scale makes the material an ideal candidate for solving the hydrogen storage problem.
The researchers are now looking at ways of printing the material onto sheets that could be stacked together and encased to form a storage tank. Potentially this tank could sit alongside a metal hydride tank and would kick into action as soon as the driver put their foot on the accelerator, giving the metal hydride store the time to heat up to 300°C - the temperature that normal petrol-powered engines run at.
“With the growing concern over climate change and our over-reliance on fossil fuels, hydrogen provides us with a useful alternative,” said Weller. “We have been able to use hydrogen to power fuel cells, which combine hydrogen and oxygen to form electricity and energy, for a number of years.
“But whenever the fuel is considered for cars we hit the stumbling block of how to store hydrogen gas in everyday applications. The new material absorbs the hydrogen into its structure and literally bristles with molecules of the gas. At the flick of a switch it rejects the hydrogen, allowing us to turn the supply of the gas on and off as we wish.
“The fact that we discovered the material by chance is a fantastic advertisement for the benefits of curiosity driven research. In principle it should be possible to produce ready amounts of hydrogen using sea water and solar cells, giving the next generation of vehicles an inexhaustible supply of environmentally-friendly fuel.
“In fact other research in Bath’s Department of Chemistry is at the forefront of the solar cell research, new battery technologies and new fuel cell technologies which could help unlock what many people are calling the hydrogen economy.
The research was initially funded by the Engineering & Physical Sciences Research Council.
The researchers are now working on the first stages of the prototype, which involves printing the material onto a glass substrate. A further £500,000 grant to the Department of Chemistry has enabled Weller along with other researchers in the Department to buy two mass spectrometers which allows them to examine the molecular structure of the material.
It was published in the scientific journal Angewandte Chemie in August 2006, and reviewed by Nature in September 2006. Copies of both articles are available from the University of Bath press office.
Although the MAIN problem of Hydrogen is the ways available to obtain it...
Producing it involves the consumption of lots of electricity and that usually comes from burning fossil fuels. So not a big help.
Read somewhere that only with nuclear power the Hydrogen will be available a prices good enough for the market... but that is feared in many countries...
Just my 2 cents.
Regards,
Vítor
After all, anything that means we can keep our nice big engined TVR's and Ferrari's and such must be a good thing?
1. The fossil energy lost while producing the hydrogen for the BMW is higher than the car would consume on regular fuel. So no benefit here in terms of nature conservancy, more the opposite of it.
2. The tank leaks, this is official and does it through a vent. Whil in the tank the hydrogen turns from liquid to gas when the temperature rises. Therefore a vent releases the pressure. After 9 days your hydrogen tank is half empty...a fact.
All together a nonsense car in my eyes.
Isn't this article about storing hydrogen, not burning it? Hydrogen is usually the "fuel" in "fuel cell", no?
FWIW, that quoted US govt target of 6% hydrogen by total storage weight seems poor (although I'm sure it's not easy to meet). That's like a 50l petrol tank having a mass of over half a tonne!
John
For driving pleasure, a combustion engine will be always preferable by me. Maybe that's because I didn't try yet a electric engine... But since they don't emit much sound...
Yes, there is still a long way to go for Hydrogen combustion... But I still believe it is the best solution.
Fuel Cell cars still burn fossil fuel right (the electric motor helps the normal engine and the batteries load during braking or descents)? If they don't, they have to be "fueled" with electricity, which is generated from power plants that most of the time, burn fossil fuels.
Half clean solutions are fine in a transition. But our goal should be 100% clean energy. Solar power, wind power, even nuclear power (if we know what to do with the waists)...
Isn't this article about storing hydrogen, not burning it? Hydrogen is usually the "fuel" in "fuel cell", no?
FWIW, that quoted US govt target of 6% hydrogen by total storage weight seems poor (although I'm sure it's not easy to meet). That's like a 50l petrol tank having a mass of over half a tonne!
John
Actually, this is about storing hydrogen in a car that burns hydrogen.
Fuel Cell cars still burn fossil fuel right (the electric motor helps the normal engine and the batteries load during braking or descents)? If they don't, they have to be "fueled" with electricity, which is generated from power plants that most of the time, burn fossil fuels.
WRONG...That's a hybrid, I have one of those already.
Fuel cell cars pass hydrogen through the fuel cell, where it reacts with oxygen to produce electricity that powers the motor, there is no I/C engine at all, the only waste product is pure, clean water.
2. The tank leaks, this is official and does it through a vent. Whil in the tank the hydrogen turns from liquid to gas when the temperature rises. Therefore a vent releases the pressure. After 9 days your hydrogen tank is half empty...a fact.
And guess what is a more potent greenhouse gas than carbon dioxide...Your basic problem is that, to make it, you need a minimum of 34 kWh of energy to “make” 1kg of hydrogen from water. And that’s at 100% efficiency, which any first year engineering student will tell you, is impossible to achieve in reality.
At the moment I think we’re hovering around about 74% efficient for electrolysis machines. So you’ll need about 46 kWh for 1kg of hydrogen.
1kg of hydrogen = about 4 litres of petrol.
Now assuming, say, 6 pence per kWh for electricity, it’ll cost you about £2.76 in electricity alone for your hydrogen. Which is equal to petrol at 69p/litre. (petrol only costs about 25p/litre before tax at the moment)
The only downside, is that this doesn’t take into account the capital cost of an electrolysis machine. Currently these are so high that they ruin the economics (ie. No petrol station could afford to install one unless they were going to charge £5 a kg for hydrogen.)
So your problem, really, is that pesky 2nd law of thermodynamics. Entropy will always increase, and you’ll never get out more than you put in.
Hydrogen is incredibly inefficient (both to make and to store) and makes me feel that it is unlikely to be much of a long term transport soloution, even if there are breakthroughs in storage.
The fact is that its far too expensive to make. And that won’t change as its governed by the laws of physics and the ever rising cost of electricity.
Andy
1. The fossil energy lost while producing the hydrogen for the BMW is higher than the car would consume on regular fuel. So no benefit here in terms of nature conservancy, more the opposite of it.
2. The tank leaks, this is official and does it through a vent. Whil in the tank the hydrogen turns from liquid to gas when the temperature rises. Therefore a vent releases the pressure. After 9 days your hydrogen tank is half empty...a fact.
All together a nonsense car in my eyes.
The first telephone was utterly useless as well when it was conceived. Oh, and the Wright Brothers didn't even bother to take a sexy stewardess on board.
How on earth did those inventions ever take off?
Your basic problem is that, to make it, you need a minimum of 34 kWh of energy to “make” 1kg of hydrogen from water. And that’s at 100% efficiency, which any first year engineering student will tell you, is impossible to achieve in reality.
At the moment I think we’re hovering around about 74% efficient for electrolysis machines. So you’ll need about 46 kWh for 1kg of hydrogen.
1kg of hydrogen = about 4 litres of petrol.
Now assuming, say, 6 pence per kWh for electricity, it’ll cost you about £2.76 in electricity alone for your hydrogen. Which is equal to petrol at 69p/litre. (petrol only costs about 25p/litre before tax at the moment)
The only downside, is that this doesn’t take into account the capital cost of an electrolysis machine. Currently these are so high that they ruin the economics (ie. No petrol station could afford to install one unless they were going to charge £5 a kg for hydrogen.)
So your problem, really, is that pesky 2nd law of thermodynamics. Entropy will always increase, and you’ll never get out more than you put in.
Hydrogen is incredibly inefficient (both to make and to store) and makes me feel that it is unlikely to be much of a long term transport soloution, even if there are breakthroughs in storage.
The fact is that its far too expensive to make. And that won’t change as its governed by the laws of physics and the ever rising cost of electricity.
Andy
All very true until someone finds a better way to obtain hydrogen. Possibly there is a chemical containing it that is easier to dissasociate the hydrogen from, or a catalyst or reagent that displaces it from water. Time will tell what happens.
That happened to the butanol from ethanol thing? Sounds like that would be a hell of a lot simpler. The argument against it was the energy used to distil alcohol was more than you got out of burning it. Alcohol is distilled at 70C. Crude oil is distilled at a fairly high one if I remember correctly and you dont have to faff about with different fractions when distilling alcohol. If it was distilled on the same scale oil was fractionally distilled would that argument still hold?
ENERGY POLICY - AN ENGINEER'S VIEW
given by:
Professor Michael Laughton, Emeritus Professor of Electrical
Engineering at the University of London
With the extensive use of equations, Professor Laughton demolished
the idea of a hydrogen future. He found water supply and carbon sequestration problems in the manufacture of hydrogen by electrolysis or by
reforming natural gas.
Hydrogen manufacture could never solve the energy problem
because it required more energy to produce hydrogen than could be
got out of it. This meant that, since hydrogen had to compete on cost with its own energy source, it could never win.
The inefficiency of a hydrogen economy was given by the laws of
physics that could not be changed by research programmes, votes of Parliaments, presidential initiatives or capital investments. "A hydrogen
economy", he concluded "has no past, no present and no future".
===================================
So IF there were no 'fossil' fuel options and IF electricity storage proved unsuccessful for vehicles as a means of energy provision (are they?) then MAYBE Hydrogen as a combustion fuel MIGHT become viable no matter what the cost but only IF there is a way to store and transport it in bulk. Both in the car and in the replenishment network. And without impossible to absorb overheads and high physical risks related to storage engineering.
As others have mentioned already there are sopme problems with the laws of physics to be overcome. Even if that sort of progress in physics is possible - and boy what would that mean to everything we currently think we understand! - it is not going to happen in my lifetime.
Now we can't go back to animals - too much methane production and CO2 from them. Can't walk - too much CO2 AND the carbon sequestered in our obese bodies would be released back to the atmosphere. Burning hydrogen would free up Water for evaporation. Have we got enough water we can dessicate? I suppose we might have once we burn the hydrogen to get the clouds that will give us rain ... that we need to have enough water to drink, irrigate and, er, produce hydrogen.
Hmm.
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