Hydrogen cars, unlike many of the hybrid and "green" cars currently on the market, offer zero emission technology, where the only byproduct from the cars is water vapor. Fossil fuel burning vehicles emit all sorts of pollutants such as carbon dioxide, carbon monoxide, nitrous oxide, ozone and microscopic particulate matter. Hybrids and other green cars address these issues to a large extent but only hydrogen cars hold the promise of zero emission of pollutants. According to the US Environmental Protection Agency fossil fuel automobiles emit 1 ½ billion tons of greenhouse gases into the atmosphere each year and going to hydrogen-based transportation would all but eliminate this.
Why should I be aware of this?
Hydrogen cars are not only the future, they are already here. The Honda FCX Clarity is among the first hydrogen fuel cell-powered sedan currently available on a limited retail basis in the US. Ford Motor Company has introduced the P2000 with a hydrogen internal combustion engine to help bridge the gap between gasoline vehicles and the fuel cell vehicles of the future. Japan too has many hydrogen cars used as fleet vehicles now.
Carbon dioxide emissions have been a major cause of the ozone depletion. A large contributor to these emissions is the exhaust from the cars we drive. Hydrogen proves to be a more environmental friendly fuel.
Hydrogen vehicles and environment
Fossil fuels release the gaseous form of carbon monoxide as cars consume them. Carbon monoxide can be harmful to people and animals since it causes lowered blood circulation in the body. This, along with other harmful substances released by gasoline, gradually reduce the protective cover of the ozone layer and contribute to global warming.
Hydrogen, on the other hand, does not turn into any particularly harmful substance as it is burned, making it environmentally friendly. In fact it only turns into water. The products of a hydrogen fuel cell are electricity, heat, and water, from which electricity is used to power the vehicle containing the fuel cell.
It is an excellent vehicle fuel primarily because it is not toxic, poisonous or corrosive. It doesn't harm the environment or public health. Even if it were to leak, hydrogen would disperse into the air almost immediately because it is so light. When this is compared with the effects of oil and gasoline spills, it's easy to see why hydrogen offers such an exciting future.
All about hydrogen vehicles
Hydrogen is the most versatile of renewable energy resources. It can be burned in an engine or used in a fuel cell to power vehicles, buildings and homes, utility power plants and anything else that uses electrical energy. Hydrogen is about 30 percent more efficient than gasoline when burned in an engine. When a fuel cell is used to power a vehicle, the fuel cell is 100 percent to 200 percent more efficient than gasoline.
In a fuel cell, hydrogen is not a fuel but an energy carrier which moves energy in usable form from one place to another. Electricity, the best-known energy carrier, moves the energy stored in coal, uranium and other sources from power plants to homes and businesses.
While fossil fuels produce power and carbon dioxide, hydrogen power produces energy and water. It separates the hydrogen and oxygen used into separate fuel cells where each undergoes half of a reduction-oxidation reaction. When electricity is applied to the hydrogen and oxygen the hydrogen loses electrons and the oxygen gains electrons. Following this reaction electricity allows the car to run and both water and heat are released.
Concerns about hydrogen vehicles have centered around the problem of immense pressure that is required to house the hydrogen. Also, there have been worries that such a flammable gas may be found dangerous. Another problem is the cost of hydrogen fuel centers.
Scientists are constantly finding methods for keeping the pressure secure. The flammability of the gas has also been resolved, and there hasn’t been any harmful explosion in any of the crash tests. Regarding the high cost of fuel centers, researchers believe that they can motorize these fuel centers to reduce costs.
What can I do?
- As with any fuel, it is necessary to understand hydrogen's physical qualities. It is important to remember to safely handle energy carriers like gasoline, diesel, natural gas, and hydrogen, even though all vehicles have built-in safety devices.
- The most important safety measure if to avoid a leak. If there is no leak there will be no fuel to ignite. Fuel cell cars and hydrogen fueling stations are designed to prevent hydrogen from leaking, and with the redundant systems to shut down automatically if an accident occurs.
- Most of the safety measures applicable to other fuels will apply to hydrogen also, specially during refilling. Like not smoking, not using cell phones, and not filling the car with the engine running. In some ways, hydrogen stations will be like traditional gas stations.
With the advent of hydrogen cars will the gasoline powered car become obsolete? Hydrogen cars have already reached some of the markets and in time consumers will soon find out how much better the planet will be, and how much more efficient their lives will be.
A report entitled "Transitions To Alternative Transportation Technologies: A Focus On Hydrogen", based on a study sponsored by the U.S. Department of Energy, has estimated that the maximum practicable number of hydrogen vehicles that could be on the road by 2020 is 2 million. This, according to the report, would not have a large impact on oil usage or greenhouse gas emissions.
The greatest possible reductions would occur if bio-fuels, fuel-efficient conventional vehicles, and hydrogen vehicles are all pursued simultaneously, rather than seen as competitors. 
- Hydrogen cars
- Hydrogen Use and Safety
- The Future of Hydrogen Power
- ↑ Science Daily