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What is a Hydrogen Fuel Cell?

Ken Black
Ken Black

A hydrogen fuel cell is a technology that converts hydrogen and oxygen into water, and along the way produces energy that can be used in other applications. Currently, most of the talk concerning the use of a hydrogen fuel cell is in the automotive industry. If the technology can be developed to the point it can be produced affordably, it may be the energy source for automobiles for the foreseeable future.

Most people are somewhat familiar with “fuel cells” of a different variety, commonly known as batteries. Batteries, although not technically referred to as a fuel cell, have chemicals in them that produce an electrical current. In alkaline batteries, zinc and manganese oxide are used. However, because the batteries are close-ended systems, the materials inside cannot be replaced. Therefore, they eventually lose their ability to produce current and are referred to as being dead.

Hydrogen fuel cells produce useable energy by converting hydrogen and oxygen into water.
Hydrogen fuel cells produce useable energy by converting hydrogen and oxygen into water.

A hydrogen fuel cell, on the other hand, does not have to worry about this very big inconvenience. Due to the fact that the materials needed to produce a current, hydrogen and oxygen, are constantly flowing into the cell, there is always current flowing out of the cell. This continual regeneration is one of the big advantages of a hydrogen fuel cell.

Fuel cell hydrogen cars create less exhaust emissions than cars powered by conventional fossil-fueled engines.
Fuel cell hydrogen cars create less exhaust emissions than cars powered by conventional fossil-fueled engines.

A hydrogen fuel cell, especially when used to power a vehicle, can be very energy efficient. In fact, most hydrogen fuel cells that use pure hydrogen have an efficiency rating of nearly 65 percent in automotive applications. By contrast, gasoline-powered vehicles lose a lot of efficiency through the by-product of heat. There is so much heat lost in the conversion of gasoline to mechanical energy that the overall efficiency is approximately 20 percent.

A hydrogen fuel cell offers a number of other advantages over the traditional vehicle powered with gasoline or diesel. First, a hydrogen car no carbon dioxide or other harmful emissions. The only by-product of a hydrogen fuel cell is water. Second, for those countries that do not have many fossil fuel resources, hydrogen fuel cells are a great energy source that uses virtually limitless supplies of hydrogen and oxygen in order to operate.

While the technology is currently at the level where a hydrogen fuel cell vehicle can be developed and there are even some on the road, they are still relatively expensive, compared to their gasoline cousins. The precious metals required for fuel cells and cost of other raw materials make them very expensive to produce. Many scientists feel technological advances will only make it a matter of time before those production costs start to come down. However, in the meantime, hydrogen fuel cell vehicles are still out of the price range of the vast majority of the population.

Discussion Comments

Soulfox

@Logicfest -- yes that is a problem but you've got to believe it is a temporary one. After all, hydrogen is the most common element on the planet. There's got to be a way to split it off of something and use it for fuel.

Meanwhile, there's no problem with using hydrogen as a fuel source until technology develops to the point we don't have to mine it from natural gas, gasoline or anything else. If the goal is to get away from relying on foreign oil, then using American natural gas as a source for hydrogen is a good start.

Logicfest

@Markerrag -- perhaps the biggest problem in developing hydrogen vehicles is that one of the best sources for hydrogen when it is used in fuel applications is natural gas. That's right -- a lot of companies are currently mining hydrogen from a non-renewable fuel source. That kind of defeats the purpose of using hydrogen, doesn't it?

Markerrag

A major problem with hydrogen powered vehicles is that they do produce water (and a lot of it) as a byproduct of the process. What do you do with all of that water? In warmer months getting rid of it is no problem. Let it spill on the ground and evaporate. Easy enough.

Ah, but what do you do in winter months? A bunch of hydrogen powered vehicles driving around in cold weather and spewing water on roads is a good recipe for a lot of black ice and car wrecks.

Let's hope a good solution to the problem is developed soon. Hydrogen vehicles could well be the wave of the future once the technology is perfected.

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    • Hydrogen fuel cells produce useable energy by converting hydrogen and oxygen into water.
      By: viperagp
      Hydrogen fuel cells produce useable energy by converting hydrogen and oxygen into water.
    • Fuel cell hydrogen cars create less exhaust emissions than cars powered by conventional fossil-fueled engines.
      By: Mastrofoto
      Fuel cell hydrogen cars create less exhaust emissions than cars powered by conventional fossil-fueled engines.