Hydrogen Fuel Cells: A Comprehensive Primer

Hydrogen Fuel Cells - Clean, efficient, reliable, and cost effective, the future energy source must truly be hydrogen fuel cells. With all the commotion going on about the rising gas prices, green house gas emissions, public health, and the disappearance of non-reunable energy resources, hydrogen fuel cells seem to be the Holy Grail or the priceless jewel that will solve all our energy problems. Let's take a look at how hydrogen fuel cells work and the technology behind this amazing energy resource.

Energy Transformation Equation:

Nuclear Energy - Electrical Energy - Chemical Energy - Thermal Energy

The nuclear energy of hydrogen is transformed into electrical energy when the proton and electron of it is split (the electrons are the electrical energy). Electrical energy is transformed into chemical energy when protons and electrons reattach to form hydrogen. The hydrogen reacts with oxygen releasing thermal energy.

Operation of a Hydrogen Fuel Cell:

Hydrogen fuel is injected into the fuel cell facing the anode catalyst (attached to the proton exchange membrane). The proton of the hydrogen splits and passes through the catalyst into the proton exchange membrane. The electrons go through the external circuit reaching the other side of the membrane called the cathode catalyst. The protons inside the proton exchange membrane reattaches to their counterpart electrons forming hydrogen. Air from outside the fuel cell is circulated into the area where hydrogen is reformed. Chemical reactions occur between hydrogen and oxygen generates water vapour and heat.

History:

Now that we know how hydrogen fuel cells work, let's take a look at the history of this technology. The principles of the fuel cell were discovered by a scientist named Christian Schonbein in 1838. Later on the Welsh scientist Sir William Grove used the principles to create the first fuel cell. It wasn't until 1959, when Francis Bacon developed a successful fuel cell system, that fuel cells really caught on. The same year a 20hp fuel cell powered tractor was created, the first fuel cell vehicle ever created! The American Space Program really took interest in fuel cells when in 1960 NASA started using them extensively, this eventually lead to extensive government research for the Gemini and Apollo space programs. Until the 80's and 90's, there wasn't really a wide use or option for fuel cells, namely due to the high cost. Today fuel cells are used for many practical applications.

Where it is used:

Hydrogen fuel cells are used in general applications that replace internal combustion engines. Small hydrogen fuel cells can be used to provide extra power other than batteries to power laptops and other small applications. Most hydrogen fuel cells are developed by major car companies due to their understanding that the need of a new car design is imminent develop (fossil fuels will not last). Hydrogen fuel cells are used in Hydrogen vehicles such as the Ford Focus FCV (a modified Ford Focus). Huge car companies such as Ford and GM greatly invest on hydrogen fuel cell development (ranked third on car development compared to second - hybrids and first - fossil-fuel powered automobiles). Hydrogen fuel cell developments are located in North America as well as Europe.

Advantages:

As you can see hydrogen fuel cells are used in all these applications and technologies mainly because of the following advantages:

The Efficiency: fuel cells when combined with electrical components, are more efficient then internal combustion engines, which are currently used in automobiles, their efficiency is only 30% compared to 50% for fuel cells.

Little or No Emissions: fuel cells are generally emission free, if pure hydrogen is used the only emission or by product is water vapour! If hydrogen is generated from methane or other source some carbon dioxide maybe released.

Reduction of Green House Gases: using hydrogen fuel cells can greatly reduce green house gases. The hydrogen can be generated from non-carbon sources, and because they are very efficient, little green house gases will be produced.

Reduced Dependency on Fossil Fuels and Greater Security: because the hydrogen used in fuel cells can be generated from many different sources such as natural gas, ethanol, etc, there is no one primary source for the fuel, so there is less concern of a source being wiped out.

Cost Effective: as fuel cells are used more and more in cars and other applications, the cost of fuel cells will plummet, and the fuel is generally cheaper then gas, and more efficient.

Silent and Smooth: fuel cells incorporate no moving parts and their electric motors allow a smoother start and stop, and it is quieter then internal combustion engines.

Disadvantages:

Even with all these advantages, fuel cells do come with some disadvantages:

Cost and Complexity: right now fuel cells are very expensive to create, with some hybrid cars such as the Toyota Prius selling for well over $30 000. On top of that the technology used in fuel cells is extremely complex especially since it is made of electrical components and many parts.

Difficult to Store and Distribute: the fuel used in fuel cells are not as readily available, and thus a device called a reformer is used, the device turns hydrocarbons and alcohol into hydrogen to feed the fuel cells, but unfortunately it generates plenty of heat and other gasses, reducing efficiency and causing environmental problems.

Environmental Effects: some studies claim that small amounts of hydrogen leakage from storage tanks can cause damage for the ozone layer. Also the products used to generate hydrogen can cause pollution, for example if methane is used, the procedure for generating the hydrogen cause pollutant gases to be released.

Low Temperature Problems: temperatures that are lower then -20 degrees Celsius can prevent fuel cell powered cars from starting and generally causes problems.

Availability: the fact is that there aren't many hydrogen refueling stations available so finding one and refueling can be a major problem for automobiles, especially if you don't live in the United States.

Social and Economical Factors:

Because fuel cell technology is still relatively young, there are going to be many people who will refuse and object the use of fuel cells, individuals and corporations especially. The transition to fuel cells is a very large ordeal, and can be very expensive and time consuming. The transition will cause a large replacement of equipment in factories, new training, consumer education, and since 1 in 7 people in Canada are employed in the automobile business, its going to be an especially difficult transition, will our society actually make this change, or will the technological, economical and political barriers keep us stuck to using petroleum and other fossil fuels? The worldwide market for hydrogen could also be highly competitive, as hydrogen can be produced from almost anywhere from many different sources. The premiere of fuel cells could also potentially cause current workers to lose their jobs and at the same time create new jobs and providing higher income to areas of the world that have low incomes, we have to see if this will have a positive or negative impact.

Building inexpensive, efficient, and reliable fuel cells is a very complicated procedure and business, currently fuel cells are very expensive to produce compared to internal combustion engines, so not everyone is going to want to have one. The parts used in fuel cells and their electrical counterparts have created large cost problems. The fuel used in fuel cells is still not cheap and efficient to replace traditional sources of power such as coal and nuclear power.

Finally some uncertainty remains between government officials, inventors, and scientists, on the final benefits of the fuel cell, questions still remain such as is it truly cheaper then current methods of generating power, will fuel cells really have a large positive impact on the environment, and will potential consumers accept the technology? All good questions to ponder.

Hydrogen as the main source of fuel in vehicular transportation and other applications are currently costly. This is because the main dominant fuel economies are fossil fuels and natural gas. Hypothetically, a hydrogen economy can be reached when the amount of hydrogen fuel meets or surpasses the amount of fossil fuels produced per year. Hydrogen fuel cells revolutionizes cities' pollution factor since it only generates water vapour and heat. However, most people today are fooled by the thought that hydrogen is all that clean and produces no by-product that harms the nature. Consider that 95% of hydrogen produced in the United States uses the natural gas reforming process (or steam reforming) of methane because it is the cheapest way. In steam reforming of natural gas, 7.05 kg CO₂ are produced per kilogram hydrogen. The amount of water vapour emitted by hydrogen fuel cells are approximately the same as gasoline internal combustion engines.

Conclusion:

I conclude by saying whether we accept fuel cells or not, we have to remember that it is here to stay with us, the future of energy could truly be clean, efficient, and reliable, we will just have to wait and see.