The 21st century will be a time of change, though this can probably be said of any century since the invention of the calendar. We can, however, make a pretty safe assumption about what one of those changes will be: The 21st century will see the end of the widespread use of fossil fuels. Fossil fuels, such as coal and petroleum, are the remains of prehistoric organisms buried beneath the earth's surface millions of years ago and they're in limited supply. Eventually the reserves of these fuels will give out. When this happens and preferably long before this happens , it's important that we find new ways to power our technology. In particular, vehicles that currently use internal combustion engines to burn gasoline or diesel fuel will need to run off new fuels that are less scarce and burn cleaner, reducing or even eliminating pollution.
Over the past three decades there has been considerable effort in the world to develop and introduce alternative transportation fuels to replace conventional fuels such as gasoline and diesel, environmental issues, most notably air pollution and limited availability of conventional fuels are among the principle driving forces behind this movement.
If one tries to find for the definition of perfect fuel, hydrogen probably satisfies most of the desirable characteristics of such a fuel. Plentiful and clean burning, hydrogen has very high energy content.And therefore, in light of the limited availability of fossil fuels and the rising environmental impact from harmful emissions, we are convinced that the H2 combustion engine will assume an important position
Use of hydrogen as a fuel
The properties of hydrogen that contribute to its use as a combustible fuel are its:
Wide range of flammability.
Low ignition energy.
Small quenching distance.
High auto ignition temperature.
High flame speed at stoichiometric ratios.
High diffusivity.
Very low density.
The combustion of hydrogen with oxygen produces water as its only product:
2H2 + O2 = 2H2O
The combustion of hydrogen with air however can also pro-duce oxides of nitrogen (NOx):
H2 + O2 + N2 = H2O + N2 + NOx
The oxides of nitrogen are created due to the high temperatures generated within the combustion chamber during combustion. This high temperature causes some of the nitrogen in the air to combine with the oxygen in the air.
Hydrogen has a high specific energy, high flame speed, wide range of flammability, and clean burning characteristics which suggest a possibility of high performance in internal combustion engines (ICE).
Advantages
Components and design can be very similar to conventional gasoline engines.
Produces no direct carbon emissions from combustion.
Performs well under harsh weather conditions.
Disadvantages
The large storage tanks can compromise vehicle cargo space.
Can produce slightly higher nitrogen oxide emissions compared to conventional vehicles.
Hydrogen refuelling infrastructure is limited at this time.
Current Status
A few auto manufacturers have been doing some work in the development of hydrogen-powered vehicles (Ford has recently announced that they have developed a “production ready” hydrogen-powered vehicle using an ICE and BMW has completed a world tour displaying a dozen or so hydrogen-powered 750i vehicles). However, it is not likely that any hydrogen-powered vehicles will be available to the public until there is an adequate refueling infrastructure and trained technicians to repair and maintain these vehicles.
Like current gasoline-powered vehicles, the design of each hydrogen-powered vehicle will most likely vary from manufacturer to manufacturer and model to model. One model may be simple in design and operation, for example, a lean-burning fuel metering strategy using no emission control systems such as EGR, catalytic converter, evaporate fuel canister, etc. Another model may be very sophisticated in design and operation, for example, using an EGR fuel metering strategy with a catalytic converter, multiple spark plugs, etc.
Until such time that a hydrogen infrastructure exists, hydrogen/natural gas fuel blends provide a logical transition to fully hydrogen-powered vehicles. These vehicles can operate on either fuel, depending on availability.
I think that using Natural Gas Engines is a win win situation.
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