Hydrogen is not actually a fuel. In fact, it is a way of storing or transporting energy and actually requires energy to create it.
How it Works
Energy can be created from hydrogen by using traditional engines or fuel cells. Just like with gasoline, an engine can use hydrogen as a fuel for combustion. A more efficient method of generating energy from hydrogen is by using a fuel cell. A fuel cell is a device that converts the energy from a chemical reaction into electricity. In a fuel cell, hydrogen is broken into protons and electrons. The electrons that are released are turned into an electric current. The leftover protons combine with oxygen, to form the fuel cell’s only emissions – water and heat.
Before hydrogen can be used to create energy, it must first be separated from other compounds.
Three methods are currently used:
One method of separating out hydrogen is in a process called "steam reforming." High-temperature steam separates hydrogen from the carbon atoms in natural gas. Currently this process is the most cost-effective way to recover hydrogen, but it relies on fossil fuels to produce the high-temperature steam. This doesn't really help in the effort to turn to renewable resources to meet our energy needs.
Another process used to separate out hydrogen is electrolysis. Water is split into its basic elements, hydrogen and oxygen, by passing an electrical current through it. The resulting hydrogen is extremely pure. While steam reforming relies on fossil fuels, electrolysis can use electricity generated by renewables like wind or solar. Electrolysis is much more expensive than steam reforming, resulting in a more expensive product. If technological advances could reduce the price of the process, this would be an efficient way to recover hydrogen, especially since water is such an abundant natural resource.
A third way to recover hydrogen is to burn biomass. Wood chips and agricultural wastes are superheated until they turn into hydrogen and other gases. Biomass itself can be the fuel used to superheat other biomass, making it a "closed" cycle.Once the hydrogen is extracted, it becomes a high-powered, efficient, clean energy source with almost limitless possible applications.
Currently, one of the most visible applications of hydrogen power is in NASA’s space program. Liquid hydrogen fuels NASA’s spacecrafts, and hydrogen fuel cells power the electrical systems onboard. The fuel cell's emission, pure water, is used for drinking by the astronauts.
It’s the possible applications of hydrogen that provide the real promise. Hydrogen, with its high-energy content and low weight, would be an ideal jet fuel. Hydrogen, fed through fuel cells, could power electric vehicles. Many large car manufacturers are researching and producing model cars that use fuel cells. Other companies are working on fuel cells that can provide electric power for individual homes, businesses, or cities.
Experts agree that hydrogen has great potential. Hydrogen is abundant. It can be found almost everywhere — from the water you drink, the food you eat, or the environment around you.
Its lack of weight means fuel economy could be improved with lighter vehicles. A fuel cell running on hydrogen could be very small, allowing energy to be generated closer to where it is needed – imagine generating all of the power for your home from a fuel cell in your basement.
In the event of a spill, hydrogen spreads out into the environment very quickly, making it virtually harmless. Hydrogen naturally wants to bond with oxygen, so the byproduct is water. What an excellent emission!
While hydrogen has the potential to fill many of our future energy needs, there is a lot of work that needs to be done to make it practical. Oil and natural gas can run through pipelines to move from one part of the country to another, but there is no way to ship hydrogen around within the existing infrastructure. A system of pipes or transportation methods will have to be developed before hydrogen is used on a national or even regional level.
There is no large supplier of hydrogen gas either. Large production facilities will have to be constructed. A system to store and transport the energy will have to be developed.
The technologies to utilize hydrogen as a power source will have to be developed as well. Fuel cell technology is still in its infancy, and the prototypes that do exist are very expensive. Without products that use hydrogen, there is no push to provide hydrogen. And without a dependable source of hydrogen, manufacturers are not yet investing much effort into creating products that use hydrogen
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