Hnat-Dembitz.MMA.Spring.2009.EnergyAndWater

=__**HYDROGEN FUEL CELLS**__=

Honda Fuel Cell Sports Car Concept

With the foundering economy and the high cost of fossil fuels, the world is looking for an alternative fuel source that can bring us into the next century. Fossil fuels may also be the cause of global warming and acid rain. Governments are putting money towards a variety of alternative power sources, without focusing on those that are economical and are true viable options. Hydrogen power, mainly in the form of hydrogen fuel cells has been getting much attention as of late. The promise of a device that uses a fuel that is virtually limitless and non-polluting has captured the interest of world-leading energy companies, the automotive industry, and governments. Fuel cell technology holds so much promise that a notion of a "hydrogen economy" where hydrogen is our primary form of energy has developed. Simply put, a fuel cell is a device that uses hydrogen fuel and oxygen from the air to produce electricity, heat and water. Fuel cells operate much like batteries converting chemical energy to electrical energy, except that they need a continuous supply of fuel in order to function and they do not store energy Hydrogen is the most abundant element in the universe. However, pure hydrogen is very difficult to come across on our planet. The majority of hydrogen is locked with water or hydrocarbon fuels. As a result, there is ongoing research into the most effective way of obtaining pure hydrogen. Several current production methods include: Steam reforming: Steam reforming involves burning natural gas in order to obtain hydrogen. CH4(g) + H2O(g) → CO(g) + 3H2(g) + energy Carbon Monoxide (Water Shift Gas Reaction): In this process, oxygen from a water molecule is stripped and bonded to carbon monoxide, freeing up hydrogen. CO(g) + H2O(g) → CO2(g) + H2 + energy Electrolysis: Hydrogen can be made via the electrolysis of water. However, because the electricity consumed during this process tends to be more valuable than hydrogen, very little hydrogen is produced using this method. About 4% of hydrogen is produced from electrolysis. 2H2O(aq) → 2H2(g) + O2(g) (Stricland)
 * Introduction**
 * What is a Fuel Cell?**

Anaerobic Digestion: In this process, biogas (composed mainly of methane, carbon dioxide, and water vapour) is produced, which in turn is converted to hydrogen fuel. However, the conversion process does generate some greenhouse gases. **Types of Fuel Cells** Proton Exchange Membrane (PEM) fuel cells use a solid polymer membrane (a thin plastic film) as an electrolyte. PEM fuel cells run at fairly low temperatures. Low temperatures allow the cell to have faster start-up times and enable it to quickly adapt to changes in demand for power. PEMs are also compact and produce a powerful electric current for their size. These aspects make PEMs suitable for running automobiles. Solid Oxide fuel cells are those Best suited to large central electricity generating stations. Its hard ceramic electrolyte allows the cell to operate at extremely high temperatures using relatively impure fuels. However, there may also be stability and reliability issues. Alkaline Fuel Cells are some of the oldest designs, dating back to the 1960s. It was long used by the National Aeronautics and Space Administration in the Apollo spacecraft and other space shuttles to power electrical components. The cell is susceptible to contamination, having to use pure hydrogen and oxygen. The high cost of alkaline fuel cells has also limited its use. A recent development where water is separated into hydrogen and oxygen using a solar-powered electrolyzer are Regenerative fuel cells. The hydrogen and oxygen are then passed through the fuel cells which generates electricity and water. The water is reused and the process repeats. Thus, regenerative fuel cells are basically self-contained units.(USDE) Honda's FCx Clarity

**How a PEM Hydrogen Fuel Cell Works:** A PEM fuel cell consists of four main parts: a. **Anode:** the anode is the negative post that conducts electrons freed from the hydrogen molecules so they may be used in an external circuit. b. **Cathode**: the cathode is the positive post that conducts electrons back from the external circuit to the catalyst where the atoms combine to form water. c. **Catalyst**: the catalyst is a special material which assists with the reactions of oxygen and hydrogen. d. **Electrolyte**: the electrolyte is a proton exchange membrane that conducts positively charged ions and blocks electrons. The process first begins with hydrogen gas being fed to the anode where a catalyst separates hydrogen into electrons and protons Since the electrons cannot pass through the electrolyte, they are conducted through the anode and through the external circuit, powering the load. The electrons are eventually conducted to the cathode and the remaining hydrogen protons pass through the electrolyte.

Anode Half-reaction: H2(g) → 2H+ + 2e-

On the cathode side the fuel cell, oxygen is split into two atoms. The oxygen atoms have a strong negative charge, causing them to attract the two positive hydrogen ions. Thus, the oxygen atoms and hydrogen ions will combine, along with the electrons that were conducted to the cathode, forming a water molecule. This process repeats, continuing to produce power. Cathode Half-reaction: 2H+ + ½O2(g) + 2e- → H2O(g) Total Combined Reaction: H2(g) + ½O2(g→ H2O(g) (Stricland)

To start off hydrogen cell engines only uses hydrogen as fuel and oxygen as oxidant. With this said their would be no carbon admissions to the atmosphere. According to Carol Berkower, each American pumps about a average of 12,100 pounds of carbon a year into the atmosphere. That is about 33 pounds a day. From 1990 to 2003 greenhouse gas emissions from passenger vehicles have increased by 19 percent. Also Americans are increasing their number of miles they drive annually by about 34%. With these numbers we could see a big problem in the future with the amount of carbon gasses we are admitting to the atmosphere and being able to supply fuel to the worlds needs.
 * How Could it Solve Some of The Problems?**

Fuel cell engine can solve this problem. As I said earlier fuel cells use hydrogen and oxygen so their would be no admissions of carbon. If we can find a cheap way to make pure hydrogen in liquid form, I can see our greenhouse emissions being cut down drastically.(USDE)

Because of the high prices to make Hydrogen and the price the fuel cell engines, this technology has not become mainstream. Even though this is true a lot of companies say that their gonna make it available to the public in the near future. Some companies say as close as 2012.
 * Who Uses The Technology?**

NASA has been using fuel cells sine the 1970's. NASA uses fuel cells to power the shuttle's electrical systems. Also it produces pure water, which the crew drinks. The fuel cell engines on NASA spaceships also produce heat. These engines have proven themselves through time that they are vital to NASA and their accomplishments through time.(USDE)

Courtesy of [|U-212A]

Militaries around the world use fuel cells in many different ways. For example the German Military created the U-212A Submarine which has two fuel cells. This submarine is seen as the most dangerous new weapon created in the last couple of years because of their use of fuel cells. Fuel cells have no moving part so when the U-212A is under way, they are virtually impossible to be detected on Sonar. This is seen as a big threat because the U-212A has the potential to carry nuclear weapons into America's water and being able to launch them at any major city within their striking distance. (USDE)

Fuel cells are gonna be used in the future but right now has alot of problems.
 * How Would The Critics Discuss It?**

Fuel cells run best on pure hydrogen and without it the fuel cells become less efficient and won't be worth using. Pure hydrogen take a long time to make and is very expensive. The pure hydrogen is made into a liquid form. It becomes very unstable because it naturally a gas. shis makes it a very dangerous to have stored in a vehicle.

Another problem is the fuel cells themselves. fuel cell volume is much larger than a regular combustible, so it becomes a challenge to be able to put one in a car that is not too big or too small for the vehicle. Also the fuel cells are very expensive compared to their competitors who use combustible engines. if there was a problem with your fuel cell and you needed to get it fixed it would be expensive for the labor and the parts because right now their is not many companies that sell or even fix fuel cells.

Right now fuel cells are not being used in a large scale right now is that there is no incentive for large companies to use this technology. Right now fuel cells are under research in order to find a way to make it more efficient and less costly. The United States and big companies have been investing over a billion dollars into this new technology. Most scientist say the reason why fuel cells are not in use in a large scale right now is that the price to make hydrogen is too expense to make.
 * What Would it Take For Fuel Cells to be Used In a Larger Scale?**

Countries like Iceland are needed in order to make this technology a possibility to be used on a large scale. Right now Iceland has Hydrogen fuel cell gas stations off of highways to give a glimpse how the future will be. Iceland has make great strides toward the fuel cell technology. When car manufacturing companies see that countries are starting to make laws that prohibit the use of fossil fuels and only allow hydrogen, they are going to focus their interests into these type of cars. If this was to happen this could help American companies like GM and Ford because they are pretty advanced into this new technology.

There are scientists who are working on a solution to make hydrogen cheaper and faster. Plant physiologist Tasios Melis thinks that he can solve this problem with mutant algae. Tasios Melis is so far unpublished. But if it proves correct, it would mean a major breakthrough in using algae as an industrial factory, not only for hydrogen, but for a wide range of products, from biodiesel to cosmetics. If this happens there would be no reason why this technology shouldn't be used in a larger scale.(USDE)

Works Cited: Hydrogen, Fuel Cells, and Infrastructure Technologies Program. //Hydrogen Fuel Cells//. U.S. Department of Energy. http://www1.eere.energy.gov/hydrogenandfuelcells/ How Stuff Works. //How Fuel Cells Work.// Stricland. http://auto.howstuffworks.com/fuel-efficiency/alternative-fuels/fuel-cell.htm