| On a summer day in Paris in 1783, Jaques | | | | -fuelled prototypes and demonstrated driving |
| Charles did something as tonishing. He roared | | | | ranges of 200 to 300 kms. |
| 3,000 feet above ground in a balloon of | | | | |
| rubber-coated silk bag filled with | | | | By 2010 some auto companies expect the first |
| lighter-than-air hydrogen gas. Though this | | | | production of fuelcell cars to hit-the road. |
| event had no significance for the next two | | | | A hydrogen storage system must carry enough |
| centuries, yet Charles had launched a quest | | | | fuel for at least a 500 km trip and also be |
| to harness the power of hydrogen for | | | | light enough to haul around a car. For a |
| transportation. | | | | system weighing 600 kilograms (a reasonable~ |
| | | | size of a vehicle) ,six kgs. would be stored |
| Burned or used in fuel cells, hydrogen is an | | | | hydrogen. Liquified stored hydrogen can |
| appealing option for powering future | | | | improve it's stored energy density and could |
| automobiles. This nontoxic gas could serve as | | | | be used in cars, it drawbacks |
| a pollution-free energy carrier for machines | | | | notwithstanding. Neverthe less, One |
| of many kinds. When it burns, it releases no | | | | world-renowned carmakerBMW is pushing this |
| carbon .dioxide, a potent greenhouse gas. | | | | technology onto the road. The vehicle called |
| | | | HYDROGEN-7 will incorporate an ,internal |
| And if hydrogen is fed into a fuel cell stack | | | | combustion engine capable of running on |
| a battery like device that generates | | | | either gasoline for 500 Kms.or on liquid |
| electricity from hydrogen and oxygen it can | | | | hydrogen for 250 kms. |
| propel an electric car or truck with only | | | | |
| heat and water as by products. Fuel-cell | | | | Chemical compaction: to raise energy density |
| powered vehicles could offer more than twice | | | | scientists have been able to take advantage |
| the efficiency of today's automobiles. | | | | of the chemistry of hydrogen itself. In it~ |
| Hydrogen could, therefore, help ease | | | | liquid phase, hydrogen molecules contain two |
| environmental problems, including air | | | | bound atoms each. But when hydrogen molecules |
| pollution and its hazards. | | | | are chemically bound to certain other |
| | | | elements, they can be packed even closer |
| Weight for weight, hydrogen contains three | | | | together than in liquid hydrogen. |
| times the energy of gasoline (petrol) but it | | | | |
| is impossible to store hydrogen gas as | | | | Some researchers are focusing on a class of |
| compactly as the conventional liquid fuel. | | | | substances called reversible metal hydrides, |
| One of the most challenging technical issues | | | | which were discovered by accident in 1969 at |
| is how to efficiently and safely store enough | | | | the Philips Laboratories in the Netherlands. |
| hydrogen onboard to provide the driving range | | | | Investigators found that a Samarium-Cobalt |
| and performance the motorists demand. | | | | alloy when exposed to pressurized hydrogen |
| Feasible storage devices hold sufficient | | | | gas it would absorb hydrogen, somewhat like a |
| hydrogen to support today's minimum | | | | sponge soaks up water. When the pressure was |
| acceptable travel (driving range--almost 500 | | | | then removed ,the hydrogen within the alloy |
| kms)--on a fuel tank that does not compromise | | | | reemerged in other words, the process was |
| on luggage room. These tanks have to be | | | | reversible, |
| filled or recharged in a few minutes. Lot | | | | |
| many researchers in the U8 Internal Energy | | | | In the US, scientists like Jame Reilly and |
| Agency are expending considerable effort to | | | | Gary Sandrock,pioneered the development of |
| overcome these limitations. Infact, 17 | | | | hydride alloys. This work formed the basis |
| governments are committed to advancing | | | | for today's widely used Nickel-Metal hydride |
| hydrogen and fuel-cell technologies. In 2005 | | | | batteries.The density of hydrogen in these |
| the US Department of Energy provide4 $ 30 | | | | alloys is 150 % more than liquid hydrogen! |
| million to fund the 80 research projects. | | | | Such properties of metal hydrides are well |
| | | | suited to automobiles. Although the current |
| A 500 km. minimum driving range is one of the | | | | metal hydrides have limitations, many |
| principal operational aims of the auto | | | | automakers see them as the most viable |
| industry. Engineers believe that a~allon of | | | | low-pressure approaching the near future. |
| gasoline is equal,on an energy basis, to a | | | | Toyota and Honda automotive engineers, are |
| kilogram of hydrogen.(One US gallon is almost | | | | planning a so-called hybrid approach in a |
| 3.8 litres) Whereas today's automobile needs | | | | system that combines a solid metal hydride |
| about 20 gallons of gasoline to travel 500 | | | | with moderate pressure (lower than 10,000 |
| km.,the typical fuel-cell vehicle would need | | | | psi) ,which they predict could achieve a |
| only 8 kilograms of hydrogen. Several | | | | driving range of more than 500 kms. |
| automakers have tested about 60 hydrogen | | | | |