Power on tap Posted on 08/05/2006 9:31:03 PM PDT by Maelstorm
Power on tap
(New Scientist Via Thomson Dialog NewsEdge) FORGET cars fuelled by alcohol and vegetable oil. Before long, you might be able to run your car with nothing more than water in its fuel tank. It would be the ultimate zero-emissions vehicle.
While water, plain old H2O, is not at first sight an obvious power source, it has a key virtue: it is an abundant source of hydrogen, the element widely touted as the green fuel of the future. If that hydrogen could be liberated on demand, it would overcome many of the obstacles that till now have prevented the dream of a hydrogen-powered car becoming reality. Producing hydrogen by conventional industrial means is expensive, inefficient and often polluting. Then there are the problems of storing and transporting hydrogen. The pressure tanks required to hold usable quantities of the fuel are heavy and cumbersome, which restricts the car's performance and range.
Click here to learn more about e911 and its impact on VoIP Click Here to Learn How You Can Profit from IP Communications. Live, in Person at INTERNET TELEPHONY Conference & EXPO West 2006 in San Diego. Click here to learn more about e911 and its impact on VoIP Get Your IMS Education from The Expert Team at INTERNET TELEPHONY Magazine and TMCnet. This Fall in San Diego at IMS Expo.
Tareq Abu-Hamed, now at the University of Minnesota, and colleagues at the Weizmann Institute of Science in Rehovot, Israel, have devised a scheme that gets round these problems. By reacting water with the element boron, their system produces hydrogen that can be burnt in an internal combustion engine or fed to a fuel cell to generate electricity. "The aim is to produce the hydrogen on-board at a rate matching the demand of the car engine," says Abu-Hamed. "We want to use the boron to save transporting and storing the hydrogen." The only by-product is boron oxide, which can be removed from the car, turned back into boron, and used again. What's more, Abu-Hamed envisages doing this in a solar-powered plant that is completely emission-free.
Simple chemistryThe team calculates that a car would have to carry just 18 kilograms of boron and 45 litres of water to produce 5 kilograms of hydrogen, which has the same energy content as a 40-litre tank of conventional fuel. An Israeli company has begun designing a prototype engine that works in the same way, and the Japanese company Samsung has built a prototype scooter based on a similar idea.
The hydrogen-on-demand approach is based on some simple high-school chemistry. Elements like sodium and potassium are well known for their violent reactions with water, tearing hydrogen from its stable union with oxygen. Boron does the same, but at a more manageable pace. It requires no special containment, and atom for atom it's a light material. When all the boron is used up, the boron oxide that remains can be reprocessed and recycled.
Abu-Hamed and his team are not the first to investigate hydrogen-on-demand vehicles. The car giant DaimlerChrysler built a concept vehicle called Natrium (after the Latin word for sodium, from which the element's Na symbol is drawn), which used slightly more sophisticated chemistry to generate its hydrogen. Instead of pure water as the source of the gas, it used a solution of the hydrogen-heavy compound sodium borohydride. When passed over a precious-metal catalyst such as ruthenium, the compound reacts with water to liberate hydrogen that can be fed to a fuel cell. It was enough to give the Natrium a top speed of 130 kilometres per hour and a respectable range of 500 kilometres, but DaimlerChrysler axed the project in 2003 because of difficulties in providing the necessary infrastructure to support the car in an efficient, environmentally friendly way.
Engineuity, an Israeli start-up company run by Amnon Yogev, a former Weizmann Institute scientist, is working on a similar strategy, but using the reaction between aluminium wire and water to generate hydrogen. In Engineuity's design, the tip of the metal wire is ignited and dipped into water to begin splitting the water molecules. The liberated hydrogen is piped into the engine alongside the resulting steam, where it is mixed with air and burnt. Engineuity is looking for investors to pay for a prototype, and claims it will be able to commercialise its idea "in a few years' time". The US company PowerBall Technologies envisages a hydrogen-on-demand engine containing plastic balls filled with sodium hydride powder that are split to dump the contents into water, where it reacts to produce hydrogen.
Abu-Hamed says the generation of hydrogen for his team's engine would be regulated by controlling the flow of water into a series of tanks containing powdered boron. To kick-start the reaction, the water has to be supplied as vapour heated to several hundred degrees, so the car will still require some start-up power, possibly from a battery. Once the engine is running, the heat generated by the highly exothermic oxidation reaction between boron and water could be used to warm the incoming water, Abu-Hamed says. Alternatively, small amounts of hydrogen could be diverted from the engine and stored for use as the start-up fuel. Water produced when the hydrogen is burnt in an internal combustion engine or reacted in a fuel cell could be captured and cycled back to the vehicle's tank, making the whole on-board system truly zero-emission.
Hydrogen-on-demand, whether from water or another source, could address two of the big problems still holding back the wider use of hydrogen as a vehicle fuel: how to store the flammable gas, and how to transport it safely. Today's hydrogen-fuelled cars rely on stocks of gas produced in centralised plants and distributed via refuelling stations in either liquefied or compressed form. Neither is ideal. The liquefaction process eats up to 40 per cent of the energy content of the stored hydrogen, while the energy density of the gas, even when compressed, is so low it is hard to see how it can ever be used to fuel a normal car.
Hydrogen-on-demand would not only remove the need for costly hydrogen pipelines and distribution infrastructure, it would also make hydrogen vehicles safer. "The theoretical advantage of on-board generation is that you don't have to muck about with hydrogen storage," says Mike Millikin, who monitors developments in alternative fuels for the Green Car Congress website. A car that doesn't need to carry tanks of flammable, volatile liquid or compressed gas would be much less vulnerable in an accident. "It also potentially offsets the requirements for building up a massive hydrogen production and distribution infrastructure," Millikin says.
There is a potentially polluting step that has to be tackled. "You'll need an infrastructure to produce and distribute whatever the key elements of the generation system might be," Millikin warns. While Abu-Hamed's scheme still requires a distribution network and reprocessing plant, he has devised an ingenious plan that will allow the spent boron oxide to be converted back to metallic boron in a pollution-free process that uses only solar energy . Heating the oxide with magnesium powder recovers the boron, leaving magnesium oxide as a by-product. The magnesium oxide can then be recycled by first reacting it with chlorine gas to produce magnesium chloride, from which the magnesium metal and chlorine can then be recovered by electrolysis.
Solar sourceThe energy to drive these processes would ultimately come from the sun. The team calculates that a system of mirrors could concentrate enough sunlight to produce electricity from solar cells with an efficiency of 35 per cent. Overall, they say, their system could convert solar energy into work by the car's engine with an efficiency of 11 per cent, similar to today's petrol engines.
Experts are sceptical that we'll be seeing cars running on water any time soon. "It's not the kind of thing you're going to see appearing in a car in five or even ten years' time," says Jim Skea, research director at the UK Energy Research Centre in London. For example, DaimlerChrysler is now focusing its efforts on cars running on compressed hydrogen because filling stations that supply it already exist in some places.
Proponents of cars that run on water are banking that long term the idea will win out. Engineuity's Yogev claims the running costs will be comparable to those of today's petrol engines and expects to have a prototype built within three years.
My other car runs on water? Don't bet against it.
David Adam is environment correspondent for The Guardian newspaper in London
Nothing can be cleaned without something else getting dirty. |
Interesting idea, however.
"take" ==> "tank"
Actually, maybe he could attach an alternator to an electric motor. The current from the alternator would power the motor and the motor would spin the alternator. Perpetual motion at it's simplest!
Not in even ten years, eh. If this gets near to being off the drawing boards in under 50 years, I'll be shocked.
this thing just basically burns boron. however, no process is perfectly efficient, so reacting the boron with water and burning the water is releases less energy than just burning the boron. and the boron must be renewed; and due to the same ineffeciency one must pout more energy into renewing the boron than will ever be gotten out of it. So really, while this is a clever idea for using hydrogen, if it is to be used en masse it will require a huge energy input that solar power most likely cannot provide. It's clever, but the solar power is it's achilles heel.
"Hydrogen makes an excellent motor fuel," was part of the answer my friends and I received to letter sent regarding our own work in that direction, "having two and one half times the equivalent energy found in gasoline.
We laughed with we were told by investors such developments were at least three decades away.
Well, here we are, three decades on, and the same problems with the roll-out of the Hydrogen Economy are still with us.
Hydrogen explodes all at one, for example, unlike gasoline which must be atomized and, when set afire, sticks and burns something awful. Hydrogen, "go boom," but NOT when stored at ambient temperatures.
Back then, the promise was in Nickle Hydride storage, where very little heat from an element surrounding a tank, made the right compounds of nickle both absorb and the release Hydrogen efficiently enough to move pistons. Then liquid hydride technology, much of the basis of hydrogen fuel cells today, on board the Space Shuttle for example, came along.
I have demonstration films from Billings which show a rifle shot into a gasoline filled cylinder resulted in an explosive, burning fire, while the same shot into a nickle hydride tank resulted in a classic nearly invisible blue plume similar to the focused fire from a welder's torch, and no explosion.
People were still traumatized by the Hindenburg, by the way, which was an excellent demonstration of how Hydrogen can be made to burn "all at one" without the kind of napalm fire.
The only problems with the Hydrogen solution (which may also include the development of the ultimate way to store solar energy, in the cracking of water) is the choice of storage technology. The danger is just not there, it is the expense of things like hydride compounds, in the form of metal, like nickle, for example... and the availability of delivery methods, the equivalent of gas stations today.
There is no impediment from having to use electricity, since solar power may have it's ultimate use in use down times by cracking and storing hydrogen, and fears of water usage are unfounded, as well. Sea water cracks just as easily, leaving a sediment of trace elements, even metals like gold, at the bottom of the water storage tanks.... Imagine actually being able to turn sea water into gold? All as a byproduct of extracting hydrogen from sea water using solar energy.
The portability and choice of storage technologies that can ride on the frame of an automobile, and the infrastructure for distribution remain the same, seemingly small impediments that they were to the roll out of the Hydrogen Economy in 1980.
I still have a 5 gallon culligan water bottle with aluminum beer cans cut up into small strips down in the bottom. Pour lye water in and you get hydrogen gas. Then put a weather balloon over the mouth and fill in about an hour. Tie it off with a gas-soaked string and light/let it go : makes a nice burst about 200' up, great show for a HS kegger party. Actually, if you want real energy from hydrogen, see blacklightpower.com.
Read this.
http://www.freerepublic.com/focus/f-news/1666513/posts
Hy-Fuel - solar-produced hydrogen turned into liquid fuel
I remember Billings from 35 years ago... What happened to them ?
You are right. It is a pity because this is far more doable than some of the more extreme examples using compressed hydrogen. There is no zero cost solution to energy and switching to hydrogen in my opinion is one of many options. I believe the simpliest and workable solution is to build more efficient batteries combined with more efficient solar cells. Then build more nuclear and conventional power plants and then we don't have to worry about the huge expense of a new energy infrastructure and if we want to burn hydrogen we can retrofit current plants to burn it like natural gas.
I think we will see a warming to hydrogen though because of the profit nodes that can be mapped to the current profit models. I still think one of the big things that many fail to acknowlege is the likelyhood of long term effects of increased free water vapor in the atmosphere.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.
The Law of Conservation of Dirt: