Barbato.Andrew.spring.wiki.2011

Hydrogen Fuel Cells
 "As we explore ways to bring price relief and bolster our country's energy independence, one significant energy source has emerged as a potential solution, hydrogen fuel cells." ~ Dan Lipinski

 "Fuel cell vehicles run on clean-burning hydrogen and are three times more efficient than the traditional combustible engine." ~ Albert Wynn

In past decades, concern has been growing about energy consumption and finding a more fuel efficient way to create power. Internal combustion engines are not doing the job and are producing too much carbon dioxide. People are trying to create less carbon dioxide to save the planet but switching all vehicles and major power plants to fuel cells would greatly decrease the amount of carbon dioxide produced.

**Definition** A fuel cell in the most basic sense is a converter which utilizes a fuel and an oxidant to release stored chemical energy. Unlike a battery, a fuel cell is an open system which requires an outside source of fuel. But unlike an engine a fuel cell has few to no moving parts with would hinder reliability. Contrary to popular belief, fuel cells do not have to run on hydrogen gas. In fact, there are numerous fuel cell theories which utilize all different types of fuel and oxidant compounds, most of which have hardly been researched at all.

**History** The first fuel cell was created in 1838 by William Robert Grove. It ran on hydrogen and oxygen. William Robert Grove actually had no idea how the fuel cell actually worked. It was not until 1893, when Friedrich William Ostwold solve the problem of Grove's fuel cell, that the fuel cell was actually accepted in the scientific community. The popularity from then on has skyrocketed. Over the 120 years there have been many new types of fuel cells that have begun to emerge.

The proton exchange membrane fuel cell, also know as the PEM fuel cell was invented by the General Electric company in the early 1960's. This fuel cell was originally developed for use in the American Armed Forces but it reached far above and beyond its desired goals. The PEM fuel cell is extremely expensive to produce, since it contains pure platinum catalysts. The PEM fuel cell has to undergo modifications every couple years in order to ensure that its technology is as inexpensive and up-to-date as possible. GE soon realized that this fuel cell would be incredibly efficient when running in reverse-electrolysis mode, producing oxygen for submarines and other underwater environments. Soon after the reversible PEM fuel cell was developed. It can run both in current producing mode with readily available hydrogen and oxygen and it can also run in electrolysis mode with a readily available power source.

The proton exchange membrane fuel cell is considered to be the best type of fuel cell and is widely being used in car prototypes. Many scientists think that the PEM fuel cell is going to replace the internal combustion engine. The fuel cells electrolyte is made up of a polymeric membrane and uses platinum electrodes. The fuel cell runs at a particularly low temperature (100C) and is perfect for cars because it can adapt to the cars power demands.

**How a Fuel Cell Works** 

A fuel cell has three main parts, the cathode, the anode, and the membrane. The hydrogen goes through the anode and is broken down into H + ﻿ ions and electrons. Then the H + ions travel through the membrane. The membrane only allows positively charged ions to pass through it. The hydrogen then recombines with the oxygen at the cathode and produces water. This water then flows out of the cell. The electrons that were first created at the anode travel to a connector and can power anything that runs on electricity.

**Equations** Fuel cells do not essentially purify water it generates it and creates no carbon dioxide. In the overall cell reaction you can see that the hydrogen and oxygen combine to make water. Depending on how much oxygen and hydrogen you have determines the amount of water created.

﻿Anode Reaction: 2H 2 => 4H + + 4e - <span style="font-family: 'Times New Roman',Times,serif;">Cathode Reaction: O 2 + 4H + + 4e - => 2H 2 O <span style="font-family: 'Times New Roman',Times,serif;">Overall Cell Reaction: 2H 2 + O 2 => 2H 2 O

<span style="font-family: 'Times New Roman',Times,serif;">**Pros and Cons** <span style="font-family: 'Times New Roman',Times,serif;">Each type of fuel cell has its advantages and disadvantages. The PEM fuel cell operates at low temperatures, which is good for vehicles and other machines, but the disadvantages of the PEM fuel cell is that it only is 36-38% efficient in converting H ﻿2 ﻿ power to electricity. The most efficient fuel cell is the AFC fuel cell which is from 50-60% efficient but this runs at temperatures of 80-250 C. Solid Oxide fuel cells can run at temperatures from 800-1000 C but are 50-55% efficient. People are not using fuel cells yet because to use them cars would have to store hydrogen instead of gasoline. Even though gasoline and hydrogen are both flammable, hydrogen creates a much larger explosion. Most people are also afraid of the unknown. The only thing they ever heard hydrogen used for in powering a vehicle was probably the <span style="font-family: 'Times New Roman',Times,serif;">Hindenburg. Since that ended with an explosion most people are afraid to use hydrogen as a fuel.

<span style="font-family: 'Times New Roman',Times,serif;">**Uses** <span style="font-family: 'Times New Roman',Times,serif;">Right now there are many uses for fuel cells. They can power anything from as big as a boat to as small as a highway sign. Even some wastewater treatment plants and landfills are using direct methanol fuel cells. Hospitals and police stations are also starting to use fuel cells to power their buildings. There are more than 2,500 fuel cell systems that have been installed in stationary buildings around the world. The fuel cells are favored because they are more efficient and they reduce noise and air pollution. If the fuel cells are used in a cogeneration system they can reduce the buildings energy costs by 20-40% and increase overall efficiency to 85%. Fuel cells have been proven to be 99.999% reliable. About 50 buses running on fuel cells in North and South America, Europe, Asia, and Australia. Fuel cells would be perfect for forklifts because of the constant starting and stopping the forklift does. Fuel cells are low maintenance and would be more cost effective than the battery powered forklifts because of the constant refilling and changing of the battery. Fuel cell planes are now in planning. The military is very interested in creating a fuel cell powered stealth plane because of the low noise, low thermal signal, and ability to maintain a high altitude.

<span style="font-family: 'Times New Roman',Times,serif;">Fuel cells can also be used in potable power. Fuel cells provide electricity where ever it is needed. They can replace generators when camping. The fuel cells would be replacing a large, loud, polluting generator with a small, quiet, eco-friendly fuel cell. The soldiers enjoy fuel cells for portable power because they are much lighter than batteries and last much longer. The fuel cells could also revolutionize the electronics world by providing power to cell phones and laptops for much longer time periods than a battery. Companies have shown a fuel cell power a cell phone for 30 days straight without recharging it. Laptops could run for about 20 hours straight. These smaller fuel cells could be used to power anything from power tools to smoke alarms. The fuel cells can by used to power things of any shape or size.

<span style="font-family: 'Times New Roman',Times,serif;">The world needs to start thinking about switching to using different types of energy. More efficient and less emissions is the goal of many engineers. In the near future the price of oil will be too expensive and people will be seeking alternatives. Fuel cells is a very cost effective alternative. All power created now should be created by fuel cells. They are much more efficient and a smarter choice for engineers.

<span style="font-family: 'Times New Roman',Times,serif;">**Project Driveway** <span style="font-family: 'Times New Roman',Times,serif;">Major car makers across the world are all working to make a car that runs on a fuel cell. In the fall of 2007, GM started a promotion called "Project Driveway" where drivers got to test drive 100 fuel cell powered cars around the country. The people test driving had to be from different parts of the country so GM decided to split the fuel cell fleet into three different parts of the country. The cars went to drivers in New York, Washington D.C., and Southern California. The fuel cell vehicles look exactly like the Chevy Equinox from the outside, but the inner workings are much different between a fuel cell and internal combustion engine.

<span style="font-family: 'Times New Roman',Times,serif;">media type="youtube" key="-MU4__nD8d8" height="349" width="425"

<span style="font-family: 'Times New Roman',Times,serif;">Fuel cells are the future for producing power.
<span style="font-family: 'Times New Roman',Times,serif;">Works Cited: <span style="font-family: 'Times New Roman',Times,serif;">http://www.fuelcells.org/ <span style="font-family: 'Times New Roman',Times,serif;">Kutz, Myer. //Environmentally Conscious Alternative Energy Production//. Hoboken, NJ: John Wiley, 2007. Print.