Hydrogen Powered Cars

Hydrogen Powered Cars
A hydrogen vehicle is a vehicle that uses hydrogen as its onboard 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.

Proposed hydrogen power, for powering cars, possesses a number of problems. The transportation and storage of hydrogen would be a relatively difficult thing to do. It can react spontaneously with the oxygen in the air (sunlight could very easily set it off and it has a 4-75% air to fuel ratio for combustion), and so any major disruption to an engine or a fuel line could result in catastrophic explosions; while gasoline needs exposure to oxygen to burn and remains as a liquid that quickly evaporates, hydrogen would naturally diffuse itself (being lighter than air and rapidly expanding) and would most likely burn spontaneously when coming in contact with the air, generating massive amounts of hot steam and fire. If a fuel tank were to be punctured, say inside of a hydrogen engine, potentially by minute amounts of hydrogen coming out of a small leak and erupting, then the entire engine could potentially erupt in a fireball as it would destroy pieces of the engine, expose more hydrogen to the air, and then cause a larger explosion until the entire engine was destroyed and more hydrogen was leaked into the air.

If we ignore the danger, it’s also highly inefficient as well. Any potential method proposed in using hydrogen would require electricity, more specifically a waste of electricity. We would end up using more energy or electricity to generate the hydrogen required to power the vehicle due to the inefficiencies in all of the process involved to create the hydrogen than if we just used straight electricity by itself. As well, many hydrogen vehicles propose methods which leak water vapor or hydrogen into the air. Water vapor and Hydrogen are both indirect greenhouse gases, and both can contribute to global warming; if cars began pumping out equivalent amounts of water vapor into the atmosphere compared to carbon dioxide, weather patterns, temperatures, and various things in nature could start to take sudden shifts. Both hydrogen and water vapor absorb energy that would ordinarily break down carbon dioxide, and water vapor acts as a greenhouse gas in and of itself; if the life of carbon dioxide in our atmosphere was doubled, or tripled for instance, which would only take a marginal increase in water vapor or hydrogen, our current temperature levels could sky rocket and global warming, among other things, could rapidly begin to exhibit significant problems.

According to the United States Department of Energy "Producing hydrogen from natural gas does result in some greenhouse gas emissions. When compared to ICE vehicles using gasoline, however, fuel cell vehicles using hydrogen produced from natural gas reduce greenhouse gas emissions by 60%.” Some of the energy present in natural gas is wasted through this process, as well. If the fuel efficiency of gasoline vehicles were doubled, for instance, you could actually produce less greenhouse gases then you would from using hydrogen vehicles based on the efficiency of their engines and the process used to generate hydrogen, which is mostly from natural gas. If hydrogen was produced through dissociation with water, then an enormous amount of electricity would be wasted. The reaction between hydrogen and oxygen is extremely powerful, and often used in rockets to get to outerspace. The same amount of energy would have to be put in order to split the bonds of hydrogen and oxygen, which are relatively strong, and so would require and enormous amount of energy.

According to the U.S. Department of Energy, fuel cells are generally between 40–60% energy efficient. In 2006, a study for the IEEE showed that for hydrogen produced via electrolysis of water: "Only about 25% of the power generated from wind, water, or sun is converted to practical use." The study further noted that "Electricity obtained from hydrogen fuel cells appears to be four times as expensive as electricity drawn from the electrical transmission grid. ... Because of the high energy losses [hydrogen] cannot compete with electricity.”

Essentially, converting electric energy into hydrogen chemical energy and then converting that hydrogen back into electricity would be a waste of electricity and enrrgy, and end up using more electricity and being more costly than if one used straight electric to begin with. Furthermore, the transportation of hydrogen would be more energy costly than that of electric grid transmission and result in potential catastrophic accidents. Of course assuming, that we somehow established an infrastructure to transport hydrogen around the United States or the world safely and developed a relatively non-hazardous method of filling a car with the hydrogen and then storing the hydrogen, we would still be emitting an enormous amount of water vapor into the atmosphere, which could rapidly change the weather over specific geographic areas where an enormous amount of cars are and potentially have a devastating effect on global warming, coupled with the potential direct greenhouse gases present in the processes used to obtain Hydrogen.

Areas with temperatures below freezing are a concern with the operation of fuel cells. Current operational fuel cells have an internal vaporous water environment that could solidify if the fuel cell and contents are not kept above freezing, or 0° Celsius (32°F). Most fuel cell designs are not robust enough to survive or operate effectively in below-freezing environments. If the contents of the fuel cell were frozen solid, especially before start up of the fuel cell, they would most likely not be able to begin working. Once running however, heat can be a byproduct of the fuel cell process, which could keep the fuel cell at an adequate operational temperature to function correctly. This of course makes startup of the fuel cell a concern in cold weather operation. Places such as Alaska where temperatures can reach −40 °C (−40 °F) at startup would not be use current fuel cells. However, Ballard Power Systems announced in 2006 that it had already hit the U.S. DoE's 2010 target for cold weather starting, which was roughly 50% power achieved in 30 seconds at -20 °C.

In short, Hydrogen is a difficult to sustain, dangerous highly reactive fuel that would be difficult to implement given the current infrastructure and even with the best theoretical estimates for fuel efficiency is still 10-20 years in the future and could potentially cause more hazardous effects to the environment and global warming than other clean alternatives or simply improved designs in modern vehicles. It is best reserved for specialist applications where Hydrogen is desired, and where in small amounts could be relatively useful and not require a changed infrastructure and reduced safety codes to be capable of being sufficiently implemented.

At least four things would be required for this to be viable in any case, chiefly being a remodeled infrastructure design for the safe transportation and deliverance of hydrogen, increased efficiency in the production of hydrogen, breakthroughs in fuel cell technology, some that solve fundamental problems with fuel cells, and the ability to store hydrogen in a reasonably sized container.
Considering that the primary source of hydrogen at the moment is natural gas and other hydrocarbons, it’s conceivable that this would benefit current petroleum suppliers, however.