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Hybrid Automobile A Hybrid Car combines electric motors and a gasoline engine to give greater performance and longer traveling distances than an electric car. At the same time, it utilizes the electric batteries to greatly reduce emissions and improve fuel consumption.


How do hydrogen vehicles work?

A Hybrid Car combines electric motors and a gasoline engine to give greater performance and longer traveling distances than an electric car. At the same time, it utilizes the electric batteries to greatly reduce emissions and improve fuel consumption.


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Old 06-25-2009, 01:17 AM
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Default How do hydrogen vehicles work?

How do hydrogen vehicles work?
There are two main kinds, fuel cell vehicles and hydrogen internal combustion engine (ICE) vehicles.

Fuel cell vehicles are electric cars. Hydrogen is pumped into a tank in the car, just as with gasoline. The hydrogen gas is then fed into the fuel cell where it is electrochemically converted into electricity -- with no combustion, no moving parts, and no emissions other than water vapor. The electricity is used to power the vehicle. A fuel cell is also 2-3 times more energy efficient than a gasoline engine.

Hydrogen ICE vehicles use a regular combustion engine modified to use gaseous hydrogen instead of liquid gasoline (much like a natural gas vehicle is modified). They burn hydrogen, but since there is no carbon in hydrogen, there are no CO2 emissions and only trace amounts of NOx (oxides of nitrogen--the air we breathe is 79% nitrogen). Hydrogen ICE vehicles are typically about 30% more efficient than comparable gasoline vehicles.

Both types can be hybridized for additional gains in efficiency, by adding an electricity storage device like a battery or capacitor.
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Old 06-25-2009, 01:20 AM
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Default How viable are hydrogen vehicles as an alternative to gasoline-powered cars?

In many ways, they are more viable than gasoline. A fuel cell electric vehicle is better suited to modern vehicles that increasingly use electrical systems in place of mechanical and hydraulic to steer, brake, and control the various functions of the vehicle. Also, in a fuel cell vehicle, the entire powertrain can be consolidated into a flat "skateboard" chassis, providing automakers much design freedom in latching all sorts of different vehicle bodies on to the chassis -- without having to work around a protruding, heat-producing engine and large mechanical driveline. A fuel cell is also 2-3 times more energy efficient than a gasoline engine.

Other vehicles that use hydrogen in a regular combustion engine are also very viable. They use existing engine technology, modified to use gaseous hydrogen. Hydrogen ICE vehicles are about 30% more efficient than comparable gasoline vehicles and produce ultra-low emissions, with no CO2.
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Old 06-25-2009, 01:25 AM
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Default Is hydrogen safe?

Most fuels have high energy content and must be handled properly to be safe. Hydrogen is no different. In general, hydrogen is neither more nor less inherently hazardous than gasoline, propane, or methane. As with any fuel, safe handling depends on knowledge of its particular physical, chemical, and thermal properties and consideration of safe ways to accommodate those properties. Hydrogen, handled with this knowledge, is a safe fuel.

Hydrogen has been safely produced, stored, transported, and used in large amounts in industry by following standard practices that have been established in the past 50 years. These practices can be emulated in non-industrial uses of hydrogen to attain the same level of routine safety.

If hydrogen has a wider flammability range than gasoline, doesn't that make it unsafe to use?
While hydrogen has a wider flammability range than gasoline, the range is only a piece of the story when considering the likelihood of a fire resulting from hydrogen escaping into the atmosphere. Each fuel has different properties that must be considered along with flammability range.

For example: Gasoline's narrow flammability range is a bit misleading, since this range can easily and often be reached through normal consumer handling of gasoline and certainly if spilled. There are of course gasoline fires but, as we know, fires certainly don't occur every time gasoline vapors are released to the open air, because the vapors fail to find an ignition source in time.

Hydrogen has a wider flammability range, but because it is lighter than air (50 times lighter than gasoline vapors and even lighter than helium) and diffuses 12 times faster than gasoline vapors do, it is very difficult for hydrogen gas to find a suitable ignition source in an open environment, like a fueling station.

Hydrogen systems used for vehicular fueling are designed to provide public safety just as gasoline systems are designed to do. While both fueling systems utilize break-away hoses, shear valves, and monitoring systems, hydrogen systems go a step further.

Hydrogen fuelers are designed as "closed" systems, meaning that the fuel is not exposed to the atmosphere - unlike gasoline which can be spilled fairly easily during refueling. This closed system design approach keeps hydrogen always within proper containment and does not allow oxygen or air to mix with the fuel, thereby eliminating one of the required combustion elements needed to create a fire. This further mitigates hydrogen's low ignition energy property, compared to gasoline, by never allowing a spark or ignition source to have any ability to interact with the hydrogen gas.

Finally, the National Fire Protection Association (NFPA) and the International Code Council (ICC) have incorporated hydrogen into their standards and model codes. These codes reflect the differences in properties between gasoline and hydrogen (and natural gas as well) through requirements related to setback distances, control systems, and other public safety elements.
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Old 06-25-2009, 01:31 AM
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Default How is burning hydrogen different than the reaction in the H-bomb?

Burning hydrogen, just like burning gasoline, natural gas, or a candle, is a chemical reaction, which means that electrons get shifted around and new compounds are made, like water, but the basic atoms remain the same.

The thermonuclear explosion from a hydrogen bomb is the consequence of a nuclear fusion reaction. During this reacton, the two isotopes of hydrogen, deuterium and tritium, collide at very high energy to fuse into helium nuclei, releasing tremendous amounts of energy.

To get these rare isotopes of hydrogen to fuse requires extraordinary temperatures (hundreds of millions of degrees). These temperatures are supplied in a thermonuclear weapon (in this case, an H-bomb) by setting off an atomic, or fission, bomb to trigger the fusion reaction.

However, commercial hydrogen gas contains no deuterium and no tritium. Without these isotopes, it is physically impossible for ordinary hydrogen gas to produce a thermonuclear reaction under any circumstances.
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Old 06-25-2009, 01:56 AM
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Default Is Hydrogen An Alternative fuel.

Yes, very much so! Hydrogen is considered an alternative fuel for two reasons, It is renewable, and it is the most abundant element on the earth.

Hydrogen comprises more than 75 percent of the environment, so if it became a primary fuel, dependence on foreign sources of fuel would be eliminated. However, hydrogen in nature exists primarily in combination with other elements.

For hydrogen to be useful as a fuel, it must exist as free hydrogen (H2). One common source of hydrogen is water, which is 11.2 percent hydrogen by weight. Hydrogen also can be produced from biomass.
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Old 06-25-2009, 01:58 AM
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Default Extraction and Use of Hydrogen Energy

There are two ways to extract the energy contained in hydrogen: by simple combustion in ICE's or turbine engines or by converting it to electricity in a fuel cell.

Daimler-Benz AG (now DaimlerChrysler), BMW, and Mazda have developed and tested ICE's fueled with hydrogen and have concluded that hydrogen can be used successfully as a vehicle fuel. Hydrogen also can be used to power aircraft gas turbines. In 1988, a triple-jet-powered, modified Tupolev-154 airliner was flown in the former Soviet Union using liquid hydrogen as a fuel. Daimler-Benz Aerospace Airbus (DASA), in cooperation with Russia, is developing a liquid-hydrogen-powered aircraft. The only drawback is that adjustments in manufactured parts and components will be necessary to handle the cryogenic liquid hydrogen. The cryogenic temperature range is from -150 degrees Celsius (-238 degrees Fahrenheit) to -273 degrees Celsius (-460 degrees Fahrenheit).

Fuel cell drive concepts with highly efficient electric drive systems can provide fuel-efficient solutions for vehicle propulsion that are two to three times as efficient as ICE's with mechanical transmission systems. Fuel cells convert chemical energy directly to electricity, so they lose less energy to waste heat than ICE's. The electrical output of fuel cells can power an electric motor, and vehicles with fuel cells are being developed and tested.

Several types of fuel cells are being developed. The proton-exchange membrane (PEM) fuel cell generally is considered the most promising fuel cell for automotive use, such as light trucks. The PEM fuel cell has a low operating temperature, which enables quick starts, and the amount of power it generates for its weight and size (power density) is high enough for light-duty trucks. Several experiments are being conducted in Germany using PEM-fuel-cell-powered buses. The fuel cells, coupled with electric drive motors, are able to move 18-metric-ton buses efficiently and reliably.
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Old 03-23-2010, 04:32 PM
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Default Re: How do hydrogen vehicles work?

Solid oxide fuel cells that work on almost any hydrocarbon based fuel are much more competitive and attractive, especially for transport than the hydrogen fuel cell, which will only work with pure hydrogen. Several prototype cars using solid oxide fuel cells have been built and the overall performance seems to be better than hydrogen based fuel cell cars. Further although hydrogen is the most abundant element in the Universe, you cannot just dig a hydrogen well and pump it out, since it is lighter than air it simply escapes into the atmosphere. The only way to extract hydrogen is by 'cracking' hydrocarbon fuels such as petrol! This is far more costly and wasteful than just using the petrol in its original state. Solid oxide fuel cells have overcome this problem.

Last edited by prospero; 03-23-2010 at 04:36 PM.
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Old 01-20-2011, 01:50 AM
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Default Re: How do hydrogen vehicles work?

Hydrogen can be used as a fuel source in a combustion engine designed to burn hydrogen instead of gasoline. Hydrogen-burning combustion engines operate much like engines in most cars today, except for modifications in the fuel storage and engine body. They burn hydrogen as a fuel source and emit no emissions. While this technology is available today, the infrastructure to supply hydrogen to these types of vehicles is small, and the costs to build and maintain the equipment are much higher than for gasoline-powered cars and trucks. Some hydrogen-powered vehicles are used by large municipal entities.

Last edited by cosmo; 07-08-2012 at 04:28 AM.
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Old 09-12-2011, 04:56 PM
lucacoleman lucacoleman is offline
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Default Re: How do hydrogen vehicles work?

I hope that big car companies offer this type of vehicle for the public. This will greatly reduce the use of fossil fuel and save our environment.
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Old 09-19-2011, 01:00 PM
alaina alaina is offline
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Default Re: How do hydrogen vehicles work?

Hi,
A hydrogen vehicle is a vehicle that uses hydrogen as its on-board fuel for motive power. Hydrogen vehicles include hydrogen fueled space rockets, as well as automobiles and other transportation vehicles. The power plants of such vehicles convert the chemical energy of hydrogen to mechanical energy either by burning hydrogen in an internal combustion engine, or by reacting hydrogen with oxygen in a fuel cell to run electric motors. Widespread use of hydrogen for fueling transportation is a key element of a proposed hydrogen economy.Thanks
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