Fuel+Cells+-+Jesse+&+Brendan

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= = =Fuel Cells Background= A fuel is defined as a battery that does not need recharger as long as their is a supply of hydrogen and oxygen.The first fuel cell was created in 1893 by a man named [|Sir William Grove], who was a professor at the Royal Institute in London. He created what is called a "phosphoric fuel cell." To test that the fuel cells actually created energy, Grove made an experiment. In this experiment Grove took two platinum strips and placed them in two sealed bottles. He then added hydrogen to one bottle and oxygen to the other. These bottles were both then placed in a sulfuric acid and an electrical charge became to appear in the form of water gas bubbles in the bottles. Grove later created a "gas battery" by connecting many bottles together.

[|Ludwing Mond] and [|Chalres Langer] in 1889 came up with the name "fuel cell" when they tried to make the first all time device with coal gas and air. In 1932 an engineer named [|Dr. Francis Thomas Bacon] continued to improve Mond and Langer's "fuel cell." He replaced the platinum, electrodes with nickle gauze which was less expensive and also replaced the sulphric acid with alkali potassium hydroxide. He changed this because the new substance was less corrosive. This new fuel cell was call the "Bacon Cell." Bacon created a 5 kW stationary fuel cell. In 1959, a team led by a man named Harry Ihrig built a 15 kW tractor. This new fuel cell used potassium hydroxide for the electrolyte and compressed hydrogen and oxygen for the reactants. The United Technology Corporation was the first company to make a large fuel cell plant. UTC has 200 kW of energy this powers hospitals, large office buildings, and universities.

=How Do Fuel Cells Work?= A [|fuel cell] is designed to convert combine hydrogen and oxygen gas into water, and during the process, create electricity used to power whatever needs to be powered. It is similar to a battery in that they both convert chemical energy into electricity, but the a battery will stop working after a certain point, because the chemicals are stored inside of it and will eventually run out. In a fuel cell, the hydrogen and oxygen are not stored in the cell, and therefore as long as there is enough hydrogen and oxygen, the fuel cell will operate proficiently.

The main type of fuel cell that will be covered here will be [|Polymer Exchange Membrane Fuel Cells] (PEMFC), which will most likely become available for portable usage such as cars and other means of transportation, in the future.

A PEMFC has four main parts. They are:
 * The anode
 * The anode is the negative end of the fuel cell. Hydrogen travels through channels in the anode to reach the catalyst
 * The cathode [[image:http://static.howstuffworks.com/gif/fuel-cell-parts.jpg width="307" height="203" align="right" caption="Components of a Fuel Cell"]]
 * The cathode is the positive end of the fuel cell. Oxygen travels through the channels in the cathode to reach the catalyst
 * The catalyst
 * The catalyst helps the hydrogen and oxygen molecules to combine to create H 2 O or water. The surface of the catalyst is not smooth, so that the areas where hydrogen and oxygen meet can be maximized
 * The electrolyte
 * The electrolyte is a semipermeable membrane that is located in between the cathode and anode. It is only allowed to let positively charged ions through, which blocks negatively charged electrons from passing through it and interfering with the chemical reaction

=Chemistry Behind Fuel Cells=

The first step in a fuel cell reaction is hydrogen atoms entering the fuel cell at the cathode from their external source. They are ionized there, which means they lose their electron and now have a positive charge. This is because hydrogen atoms have one proton and one electron. Protons have a +1 electrical charge, and electrons (e) have -1 electrical charge. The equation for what happens here is:
 * 2H 2 --> 4H + + 4e -

With no electrons, the hydrogen atoms only have one proton and therefore have a positive charge now. The negatively charged electrons are directed to a circuit outside of the fuel cell. This is the electricity that is used to do something useful such as power a motor or an engine. The positively charged hydrogen atoms then are forced through a catalyst on their side to the electrolyte and to the other catalyst on the other side of the fuel cell.

Oxygen also enters into the fuel cell, at the anode, and is pumped through its catalyst where it is changed from O 2 gas to two oxygen atoms. Each oxygen atom has a negative charge. Because the hydrogens atoms have a positive charge and the oxygen atoms have a negative charge, they will be attracted to each other like opposite sides of a magnet. Two hydrogen atoms passing through the electrolyte are attracted to one oxygen atom, and at this point two of the electrons from the external current join the hydrogens and oxygen, forming a molecule of water. The equation here is: Therefore, to get the net equation for the reaction in a fuel cell the two equations are combined:
 * O 2 + 4H + + 4e - --> 2H 2 O
 * 2H 2 --> 4H + + 4e - is combined with O 2 + 4H + + 4e - -->2H 2 O to get:
 * 2H 2 + O 2 + 4H + + 4e - --> 2H 2 O + 4H + + 4e -
 * The molecules that are the same on the reactants side as on the products side can be cancels out, so the net equation for the reaction in a fuel cell is 2H 2 + O 2 --> 2H 2 O

This reaction does not produce enough electricity to power a motor by itself. It only will yield about 0.7 volts of electricity. Therefore, many separate fuel cells are put together to form a fuel cell stack. Bipolar plates, or plates that have a poles (one positive end and one negative end) connect the fuel cells, and the electrical circuit connects each end of the bipolar plates. This finalizes the fuel cell.

=Types of Fuel Cells=

Their are six types of fuel cells that can be used to produce rechargeable energy. The six types are; Polymer exchange membrane fuel cell (PEMFC), Solid oxide fuel cells (SOFC), Alkaline fuel cells (AFC), Molten-carbonate fuel cell (MCFC), Phosphoric-acid fuel cell (PAFC), Direct-methanol fuel cell (DMFC).
 * [|Solid Oxide fuel cells]** are most likely used in large stationary places like running factories or even towns. This type of fuel cell only runs at very high temperatures (700 to 1,000 degrees Celsius.) Solid oxide fuel cells can have problems when they are not run constantly because they are running at such high temperatures and when they shut down it takes a very long time to being generating energy because the temperature is so high, also they can run for the longest amount of time over an other fuel cell. Microscopic defeats in the anode, cathode, and electrolyte can shut the whole fuel cell down. Also, because the temperature in which they are being generated at is so high, the steam can be sent through turbines to create even more energy. Creating energy from the steam is called co-generation of heat and power (CHP.) Only natural gas is used to run the fuel cell, so the emission of Carbon Dioxide is one-third less per kilowatt-hour than a normal internal combustion engine.


 * [[image:http://www1.eere.energy.gov/hydrogenandfuelcells/fuelcells/images/fcell_diagram_alkaline.gif width="193" height="206" align="left" caption="Alkaline Fuel Cell"]][|Alkaline fuel cells]** were created in the 1960's making them the oldest fuel cells. These fuel cells must be run with very pure hydrogen and oxygen because they are very susceptible to contamination. Carbon dioxide poisons the fuel cells, so Alkaline fuel cells work very well in space or in underwater machinery. They are the most efficent fuel cells made and can reach up to 70%. NASA has used Alkaline fuel cells since the 1960's and sent the first man to the moon in the Apollo Mission. These types of fuel cells can be the cheapest form because a number of different chemicals can be used. Also, unlike Solid Oxide fuel cells, Alkaline fuel cells do not require high temperatures to run them (65 degrees Celsius to 220 degrees Celsius.) They can be run very efficiently and quickly because of the lower temperature, they only run for about 8,000 hours, while most economic companies need about 40,000 hours.
 * [|Molten-Carbonate fuel cells]** are fuel cells that are run at very high temperatures (600 degrees Celsuis and above.) These fuel cells are run at such high temperatures that non-precious metals can be used. Also, another positive thing from the high temperatures is that the conversion of fuels to hydrogen can happen internally rather than externally. Molten-Carbonate fuel cells are at about a 60% efficiencies and then when the wasted heat is converted to energy it is as high as a 85% efficiencies rate. This type of fuel cell is not prone to being poisoned by carbon dioxide, so coal and fossil fuels can even be used to make hydrogen. Molten-Carbonate is very prone to corrosion because of the high temperatures.


 * [[image:http://z.about.com/d/alternativefuels/1/0/H/9/-/-/fcell_diagram_pafc.jpg width="178" height="249" align="left" caption="Phosphoric-acid Fuel Cell"]][|Phosphoric-acid fuel cells]** were the first commercially used fuel cells. This type of fuel cell is very expensive because the electrodes are made of carbon paper coated with platinum catalyst. They operate at about 150 degrees Celsius to 200 degrees Celsius making them the main source of the fuel cell market. The efficiency is only about 37% to 42% but when the water is converted to steam which automatically happens because of the high temperature in the fuel cell, it can become 80% efficient. Carbon Dioxide does not effect these fuel cells and can be run on reformed fossil fuels. Phosphoric-acid electroyltes can also operate above the boiling point of water.


 * [|Direct-methanol fuel cells]** operates from about 50 degrees Celsius to 120 degrees Celsius. Methanol is used at the main source of fuel, about 1M of methanol solution is normally used to carry out the process. During the stage of cross over often half of the methanol is lost. The lower the concentration of the solution the less methanol that will be lost during the cross over, but the lower the maximum power will be. Also, due to the anodize reaction, water is lost, which is called "water drag" and water is needed to steadily operate the fuel cell. Direct-methanol fuel cells are very good for objects that need a very low energy for a long period of time like a forklift.

**Applications in Real Life**

There are many real life applications for fuel cells. They provide a much cleaner energy than carbon based fuels, and are being used in transportation vessels today. In the future, these fuel cell vehicles will be used more commercially. Examples of fuel cell vehicles are:

**[|Fuel cell ships.]** The world's first fuel cell ship, //The Viking Lady,// was launched on December 21, 2009 in Norway. It utilizes a 320-kilowatt molten-carbon fuel cell, that runs on natural gas, and operates at 650 degrees Celsius. The fuel cell will look to cut down on the ship's carbon emissions by fifty percent. The //Viking Lady// reduces nitrogen oxide emissions by ninety percent, and carbon emissions by twenty percent, even before the fuel cell is taken into account. The ship docks around once a week at one of the fifteen stations only the Norwegian coast to refuel the natural gas (the ship's tank holds 220 cubic meters of liquid natural gas), however, it can also burn diesel fuel if necessary. Also, this saves the ship money, as natural gas is actually cheaper than diesel. This is one step in reducing nitrogen oxide and carbon dioxide emissions which shipping contributes to roughly three percent of the total in the world.
 * [|Fork Lifts and Pallet Trucks.]** At a Wegmans warehouse in central Pennsylvania, employees now uses fuel cell power equipment to move around their produce. The switch to fuel cells was not with the environment in mind, but rather to help increase productivity of the warehouse. Battery powered fork lifts require eight hours to charge, and to run at night, the forklifts needed another power source. Also, the battery life decreases over time, and eventually dies out. By switching to fuel cells, the fork lifts can run at night and during the day, because fuel cell tanks do not need to charge, and a fuel cell does not "die" with use. Hydrogen lasts twice as long as a battery. A fuel cell costs $17,500 as opposed to the $2500-$3000 for a battery, but over the life of a fuel cell, the warehouse saves about ten percent in costs because they do not need to replace, clean or maintain the cell.


 * [[image:main.jpg width="504" height="225" align="left" caption="The Workings of the FCX Clarity"]]Cars.** Many car companies are looking into creating fuel cell cars to be used in the near future. Honda has released it [|FCX Clarity], which runs on proton exchange membrane fuel cells, and a battery. The hydrogen is pumped into the car, similar to gasoline, and the oxygen is taken from the atmosphere and directed to the fuel cell stack to be used. The battery receives and stores electricity from the fuel cell, as well as from the excess kinetic energy from deceleration. When the car is idling the battery powers the air conditioning and other processes. The only biproduct of the Clarity is water from the fuel cell, which can then be converted back to hydrogen and oxygen gas through electolysis. This creates a continuous cycle of renewable energy. The car runs mainly on the fuel cells, and can reach a top speed of 100 mph. The fuel cell stack gives a max o[[image:http://www.gotbroken.com/wp-content/uploads/2009/03/2007-ford-edge-with-hyseries-drive-front-side-view-588x441.jpg width="267" height="190" align="right" caption="The HySeries Drive"]]utput of 100 kW. The range is 240 miles on a 171 liter tank.

Ford has also released a fuel cell car, the[| HySeries Drive]. It runs in a similar way, using hydrogen and oxygen as the source of fuel. It runs on electricity form the battery until the batter reaches 40 percent, and then the fuel cells automatically take over and charge the battery and run the car. The range of the HySeries is 305 miles, and has a max speed of 85 mph.
 * [|NASA.]** NASA has been using fuel cells in its space program since the Apollo Missions. One big reason for this is that they can operate at temperatures that are lower than normal. NASA employs Alkaline fuel cells to power its space shuttles. The Glenn Research Center at NASA was responsible for creating the technology in fuel cell vehicles. They are currently trying to create fuel cells for more versatile uses such as the International Space Station, ways to create energy on the moon and Mars, and aircraft that run without emissions. NASA plans on using PEMFC to power its shuttles in the future, and could potentially uses the water created as water for the crew.

**Works Cited**

"A Basic Overview of Fuel Cell Technology." //National Museum of American History//. Smithsonian Institution, 2008. Web. 04 June 2010. .

Biello, David. "Observations: Can Solid-oxide Fuel Cells like the Bloom Box Remake the Energy Landscape?" //Scientific American// 05 Mar. 2010. //Science News, Articles and Information | Scientific American//. 05 Mar. 2010. Web. 04 June 2010. .

Biello, David. "World's First Fuel Cell Ship Docks in Copenhagen: Scientific American." //Scientific American// 21 Dec. 2009. //Science News, Articles and Information | Scientific American//. 21 Dec. 2009. Web. 04 June 2010. .

Brubaker, Harold. "Hydrogen Fuel Cells Power Wegmans Produce | Philadelphia Inquirer | 05/31/2010." //Philadelphia Inquirer// 10 May 2010. //Philly.com: Philadelphia Local News, Sports, Jobs, Cars, Homes//. 10 May 2010. Web. 04 June 2010. .

"FCT Fuel Cells: Types of Fuel Cells." //EERE: EERE Server Maintenance//. Web. 04 June 2010. .

"Fuel Cell Background Information." //PAWS - Personal Accessible Web Space - Kettering University//. Web. 04 June 2010. .

"History." //FCTec Home Page//. Web. 04 June 2010. .

"Honda Worldwide | FCX Clarity." //Honda Worldwide : Honda Motor Co.,Ltd.// Web. 04 June 2010. .

"HySeries Drive™ Ford Concept Features Battery-powered, Plug-in Hybrid with a Hydrogen Fuel Cell | Ford Motor Company Newsroom." //Home | Ford Motor Company Newsroom //. Web. 04 June 2010. [].

"NASA - Fuel Cells: A Better Energy Source for Earth and Space." //NASA// //- Home.// 11 Feb. 2005. Wed. 05 June 2010. [].

Nice, Karim, and Jonathan Strickland. "How Fuel Cells Work." 18 September 2000. HowStuffWorks.com.  04 June 2010

"Types - Alkaline Fuel Cells." //FCTec Home Page.// Web. 04 June 2010. [].