April 4, 2007 4:00 AM PDT

Studying the hydrogen energy chain

Alternative-energy companies are targeting state and local governments as the places to showcase the latest hydrogen fuel technology, but there are still many issues to clear up before the technology becomes a significant part of everyday life.

Researchers look at the entire energy chain (the energy equivalent of a food chain) when evaluating a potential alternative fuel. While cars powered by hydrogen are more efficient than those powered by gasoline, the leading production method for hydrogen fuel requires a lot of electricity. And if hydrogen fuel isn't produced efficiently by this method, it becomes less viable as a fuel source overall, according to Ken Kurani, an associate researcher at the Institute of Transportation Studies at the University of California at Davis.

To create a hydrogen-based transportation system that has a low overall carbon footprint, primary methods of producing hydrogen can't be based around coal-fired power plants, Kurani said. Such a process would require a system for capturing and safely storing carbon dioxide emitted by the burning coal--a process called carbon capture sequestration. "If you burn all this coal (to generate electricity to make the hydrogen) and have all this CO2, what are you going to do with it?" said Kurani.

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In areas where such resources are abundant, solar and wind energy can efficiently produce the electricity needed for electrolysis, a step in hydrogen-fuel production that liberates hydrogen from water.

Chemical processes that produce hydrogen in a closed, looped system--where chemicals are not completely consumed or denatured--are being researched by the Department of Energy and many groups in the private and public sectors.

The DOE is also looking at tapping into nuclear facilities because they already produce waste heat that could be used to reduce the amount of electricity needed for electrolysis, according to Patrick Davis, acting program manager for hydrogen fuel cells and infrastructure technologies at the DOE.

Companies such as Ecotality are thinking of ways to generate hydrogen in a fuel-cell car as the vehicle's fuel cell needs it.

Ecotality's implementation of hydrogen-fuel technology features an apparatus called the Hydratus, which was developed by NASA's Jet Propulsion Laboratory. The Hydratus is built in to a vehicle and makes hydrogen for a fuel cell using a chemical reaction between magnesium and water to liberate the hydrogen. Drivers use a three-prong pump to fill up on magnesium pellets and water, and pump out spent magnesium oxide in powder form. The spent powder is 99.8 percent renewable and can be recycled (using electricity) right at the filling station.

While the Hydratus can be adapted for use in other settings--as a support system for fuel cells powering cell phone towers and computers, for example--its first integration will be with hydrogen buses for cities and towns, which could install their own magnesium filling stations to service their fleet. Ecotality is already in touch with several interested municipalities and expects to produce the first prototype bus by the end of 2007.

Making hydrogen available to consumers is another issue. While there are about 700 miles of hydrogen pipeline for a range of applications, mostly in the Gulf states and Southern California, there is currently no hydrogen infrastructure to support hydrogen filling stations, according to ITS' Davis.

In order to make hydrogen economically viable to transport, the gas can be stored in highly compressed form. It can also be stored in liquefied form. But compressed hydrogen or liquid hydrogen can be difficult to transport. Because hydrogen dissipates rapidly on contact with air, a tank leak, while it wouldn't lead to a flammable pool of liquid on the ground, would result in loss of product.

In addition to high-pressure cryogenic tanks, one solution being researched by DOE programs and private companies is hydrogen in a solid state, in the form of solid-state metal hydride or carbon-based materials.

Another factor affecting hydrogen's economic viability is the relatively short range of hydrogen-fueled cars. As it stands now, a hydrogen car can go no more than 200 miles between fuelings, using a tank whose fuel is stored at 5,000 pounds per square inch. Under 10,000 psi, according to Davis, enough hydrogen fuel could be stored on board a vehicle to go about 300 miles, but the technology for that type of storage capacity is still being researched.

And the technology is not cheap. The DOE estimates that hydrogen fuel cells cost about $107 per kilowatt, if the supplier produced the cells at a rate of 500,000 units per year. For the fuel to become economically viable for consumers, the cost per kilowatt would have to be $30, Davis said.

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Recombinant Water
Electrolysis can produce hydrogen and oxygen on the spot, enough to burn anything, including fossil fuels, and it only takes a little bit of solar power to make it happen. It's cheaper than we are being led to believe, and easier. Machines extract oxygen, today. And that oxygen, such as the oxygen used for home care, could be under the hood of a car and could literally transform the gasoline engine into a workable alternative.

The only reason that I don't produce this stuff myself is because I don't like cars or appreciate mandatory insurance laws. But, gasoline engines have been used with oxygen long before now, and that technology was taken off of the market because of the taxes on the gas pump that are keeping America going. If it wasn't for the gasoline taxes paying so much of our country's costs, today, I would invent the water burning engine, myself.
Posted by jack1260 (19 comments )
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Truly astounding.
Posted by billmosby (536 comments )
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The Real Solution
The real solution to the transportation issues and the energy pollution crisis (as defined by VP Gore) would be hydrogen powered municipal electric generators and public monorails, subways and speed trains that run on water.

Anyone who thinks that gas and oil don't pollute should look to the skies, where jets cause most of the cloud cover these days in the form of chem trails and comm trails (jet fuel pollutants.)
Posted by jack1260 (19 comments )
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Recombinant Water
Non-Scientific Bull !!!
Posted by BigAl31 (1 comment )
Link Flag
There is oxegen in the air now you don't have to extract it. When it burns with fossil fules you get carbon dioxide, which is what hydrogen fule is trying to prevent.

Gasoline engens have always been used with oxegen.
The cost of hydrogen is mainly a safty and distribution problem. You need to safely contain the hydrogen without the weight being to much.
Posted by stevenmcs (47 comments )
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Truly astounding indeed! Do any of you circus clowns have any understanding of physics or chemistry? Water burning engines, does it hurt to be so stupid or are you too dumb to notice?
Posted by JonFraudCarry (36 comments )
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Cars that run on water. You are a ********.
Posted by Trouser Paint (1 comment )
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Hydrogen Jet Engines
One of the greatest polluters in aircraft jet engines. WHile fuel
cells poweringt electric motors are great for cars, they aren't so
great for aircraft.

Is anyone looking at Hydrogen powered jet aircraft? After all, the
space shuttle is powered by Hydrogen and Oxygen. Using Coal
fired powerb stations to produce hydrogen is a little counter
productive, electrolysis could be the answer.

Maybe Africa could become a great producer of clean hydrogen.
Setup massive solar stations across the sahara dessert and
provide fueling stations for the world's aircraft.
Posted by Jason Vaughan (5 comments )
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Yes Hydrogen has been looked at
NASA, as part of a a zero CO2 initiative, looked at hydrogen power aircraft just a few years ago. It will work, and work well from a strictly engine performance standpoint. But there are major difficulties. The primary is that Hydrogen is just too low a density to hold all that is necessary in just the wings. like can be done with jet fuel. In a standard tube and wing aircraft (think 737), most of the fuselage volume had to be dedicated to cyrogenic liquid hydrogen tanks in order to get enough fuel on board to fly any useful distance.

Since jet fuel pretty close to diesel, the solution might be a bio-fuel source.
Posted by jlfelder (61 comments )
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Yeah, just fly over to the Sahara to refuel on your flight from San Fran to LA.
Posted by JonFraudCarry (36 comments )
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Solar Hydrogen is the best solution
If we use the sun's energy as our main source of energy, we would have equilibriated the energy balance of our planet immediately.

Wind, waves, hydroelectric dams all come from the sun and are therefore in tune with our global energy balance.

Nuclear energy is extraneous source to our planet and could easily end up warming our atmosphere if we don't pump out the heat into outer space away from our planet, not to mention that there never has been adequate solution to radioactive pollution and disposal of nuclear waste.

Fossil energy are also considered extraneous source as we have equilibriated with our planet when these materials are stored, and pumping it back will distort the atmospheric equilibrium and the extraneous sources will also end up as heat trapped by our atmosphere.

Solar electricity is thus perfect for the environment, for most of our uses, as it is the same energy that our planet gets, whether we use the solar energy or not. Using solar energy will not shift the energy equilibrium of our planet as all the energy we used ends up as heat, and if that energy comes from the sun, then there is no disturbance to our global energy equilibirum.

But we do have machines that are disconnected from our solar electricity sources and that needed fuel in most times that the sun cannot provide due to limited surface area of capture, such as vehicles we used for transportation, and thus we have to divert sun's energy into producing fuels for these disconnected machines.

There are many ways that we can produce fuel by capturing energy from the sun.

We have been producing ethanol and other gasification fuels from biomass products, which in turn are photosynthetic products powered by the sun. Producing sugars or cellulose from the sun using the best plants, the overall energy photosynthetic efficiency is about 5%. Then fermentation will take a bite at the efficiency, and the energy captured into alcohol dissolved in the brew is 55%. Then we distill the brew to produce fuel alcohol, and the best reflux distillation, we would have spent 80% of the alcohol's energy and capture only 20%. So the overall efficiency from the sun is too low, 5% x 55% x 20% which is just a tiny 0.55% overall conversion efficiency, this is less than 1%.

We have been using oil, our favorite one that we are exremely addicted (also driven by greed of mandkind), which came from fossilized plants, which used solar energy to produce those hydrocarbon with efficiencies of less than 5%, plus the geological processes for millions of years of geologic scale energy, and then we spend energy to mine it, transport it, refine it, and you can only guess that the overall efficiency of this is truly miniscule, far less than a billionth of a percent when you factor in all the energy spent.

So you say you have better efficiencies with wind power, hydroelectric dams, while it is true that the cost of electricity produced from these alternatives are very low, they are not efficient when global scale energy balance are taken into account. When we do global energy balance, we can easily see that wind power, waves, hydroelectric are all powered by the sun. What we capture is truly a miniscule fraction, less than a billionth of a percent that ends up in our homes as electricity, if we consider the solar energy spent to cause evaporation to fill the dams with water, consider how much solar energy was spent to power the winds which power the turbines. The overall efficiency of these route is very tiny fraction, it is one of the least efficient overall when we start with the energy from the sun.

Take note that all of our fuel production methods, we use more energy into producing the fuel than the amount of energy that we can take out of our fuel. All of them, there is no exception, it is the basic law of thermodynamics and no escape about it. What we have discussed are assessing the various conversion efficiencies with a global scale in mind.

I would strongly argue that the most efficient way of producing fuel is by capturing the sun's energy in the form of hydrogen. It has the highest global efficiency overall, no other alternatives exists.

While we use solar electricity as ultimately our main source, we still need to produce fuel. Thus we should use the sun to produce such fuels. So I will be discussing in the context of producing hydrogen as a fuel. Producing this fuel will not cause any global warming nor disturb's the earth's energy balance.

There are solar collectors which can directly split water into hydrogen fuel and oxygen without the use of electrolysis. Commercial scale tests in Australia and Canada have achieved overall efficiency of 43% of capturing the sun's energy into hydrogen fuel energy. That is the overall energy capture into a fuel with the highest efficiency, far higher than wind, hydroelectric, biomass, and oil sources. SHELAC labs have also achieved this feat, and it is a shame that other countries beat the US of A when it comes to advancement of such technology.

There is also the popular method of producing hydrogen via electrolysis from solar electricity. The best solar panels right now is at 50% energy conversion efficiency, with a new theroretical limit reaching 70%, from the work of researchers at UC Berkeley. Now if we use this electricity to produce hydrogen under high pressure electrolysis to produce already compressed hydrogen (no need for compressors), the conversion efficiency on proven commercial scale is about 80% from electricity to hydrogen fuel energy. Thus overall, from the sun's energy unto energy stored as fuel hydrogen, we get 40% captured directly from the sun into hydrogen fuel energy.

Either methods are truly efficient, so far efficient than biomass, plant wind, way, there is no other more efficient ways of capturing the sun's energy into fuel with an overall energy capture efficiency of 40% and greater.

We have recognized that this is the best and only solution to solve our current crisis, what we need are the implementations of various solutions, development or refinement, building infrastructures to facilitate the capture and storage. We can just put away greed and cooperate. We have technologically advanced the computers in so short a time, we can do this too.
Posted by Joe Real (1217 comments )
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I'm not if hydrogen is a good idea.
With good reason: storing all that hydrogen is a complicated, expensive proposition (hydrogen gas leaks through even very small openings in a container and does explode under the right conditions). And you can forget about storing it in liquid form (you need expensive cryrogenic storage hardware and liquid hydrogen explodes SPECTACULARLY).

I'd rather go with better means of storing electricity, especially with MIT's research into nanotube supercapacitors that promise high-density electrical storage and extremely low charging times.
Posted by SactoGuy018 (1360 comments )
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You write
"Nuclear energy is extraneous source to our planet and could easily end up warming our atmosphere if we don't pump out the heat into outer space away from our planet"

That is gibberish. While not a renewable resource all nuclear fuel is mined from the planet and then refined. The heat generated by Nuclear powerplants is no different than the heat generated by fossil fuels. Global warming has nothing to do with human generated heat sources. They are a drop in the bucket compared to the sun. Greenhouse gases are said to cause global warming, because they hinder the reradiation of heat into space. Try to learn a little science before spouting nonsense.
Posted by PzkwVIb (462 comments )
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True Except
That is all true although the best I heard of is a new technology at 40% not 50% solar efficency.

The global warming isn't from the fule we are burning. The green house gases trap the suns heat. Also Co2 can increase the amout of an arobic bacteria which produce poisonous Sufur dioxide gas. Evedence is that is what cased several prehistoric events where 80% of life died out.
Posted by stevenmcs (47 comments )
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I agree totally with this article. In addition, in the West Coast, we can use salt water to consverve scarce fresh water. Also, if hydrogen, generated from solar energy, is used to fuel generators to power the grid, we can obtain solar power 24/7 and as a bonus, we can recover the water from the exhaust and create fresh water to solve the West Coast's dire need for this resource.
Posted by H2Now (1 comment )
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Fusion power is the answer
The National Ignition Facility Project is a major DOE project being built by Lawrence Livermore. The purpose of the huge facility is to test nuclear bomb designs without having to build and explode actual bombs.
This is done by the fusion of one atom of tritium and one atom of deuterium. These two isotopes of hydrogen when fused, produce the same heat in a millisecond that all the heat sources on earth produce in one year. In fact this is how a hydrogen bomb works. A pellet containing one atom of hydrogen and one atom of deuterium is put inside an atomic bomb. The A-bomb explodes and in a mere fraction of a second, the heat from the bomb goes above 200,000 degrees Farenheit. This is enough heat to fuse the two atoms and the resulting releae of fusion heat adds to the original lower powered explosion boosting it by hundreds of times.
We won't be exploding any A-Bombs. Instead we will produce the heat with 192 low watt lasers like the kind used in classrooms for pointing at blackboards. In fact the ignition fusion in the Project will be accomplished with about five dollars worth of electricity.
If it works, we have a working design for fusion power. The government can license this to municipalities or private companies to build and run fusion plants. No more coal, gas, nuclear, wind, solar, ethanol or other polluting or otherwise inefficient forms of electrical producing plants will be needed.
The big five petroleum giants can build hydrogen electrolysis plants, build the pipelines and the gas stations all over the country. In fact they are the only ones with the capital to do this quickly. Forget all the rest. We will be using fusion power for home and business electrical and heating use, and hydrogen for transportation use. No more pollution and no more geopolitical blackmail from errant religions. It could all be in place by 2020 if we all really push it to happen quickly.
Posted by Terry Gay (127 comments )
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Fusion isn't that powerful
You should have googled your facts.
http : //hyperphysics.phy-astr.gsu.edu/hbase/nucene/fusion.html#c2

Fusion produces 676 times the average energy consumption of one us citezen per kilo gram of fule

The reaction yields 17.6 MeV of energy but requires a temperature of approximately 40 million Kelvins
Posted by stevenmcs (47 comments )
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The real identity of Hydrogen power
Come on...

We know that the easiest way to produce plenty of electricity and hot water and purified water is to do it using hydrolysis/electrolysis.

It is also the cheapest way to do all three. And that is the real problem, isn't it? Where on Earth would anyone get the money to buy and sell the souls of people who are selling out to the unmatched bribery of this generation?

Water? You are on the WATER PLANET, fool. Water can break the steel engine block when it freezes and can create enough heat to run steam engines and hot water for the entire planet when it recombines from hydrogen and oxygen.

I should joust with oil company sell-outs over whether or not water is the greatest and most abundant source of energy on Earth?

By all means, hold your breath!

I'll be back in ten minutes... (maybe)
Posted by jack1260 (19 comments )
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OK genius, tell us how to separate the hydrogen and oxygen from water. Tell us where the power to preform your miracle of "hydrolysis/electrolysis" is going to come from.
Posted by JonFraudCarry (36 comments )
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why are we not using Active and Potentially Active Volcanoes to generate electricity to run ac cars and trucks?
Posted by braveheart123456 (1 comment )
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