Fuel CellsBy:Rishab PohanePranav SubramanianAayush Verma

What is a fuel cell?● “Electrochemical energy conversion device”● Converts hydrogen and oxygen into electricity, heat, and

water● Similar to batteries, but never die

o “Gas battery”

How does it work?● Convert chemical energy into

electrical energy● Fuel cells combine the chemicals

hydrogen and oxygen to generate electricity (water is also produced)

● The hydrogen is usually in the form of a fuel while the oxygen is taken from the air

● Use electrical energy to do mechanical work

● Provide DC voltage to electrical appliances

http://americanhistory.si.edu/fuelcells/images/fc_ani.gif

Different Types of Fuel Cells● Depends on electrolyte that is used.

● Polymer electrolyte membrane fuel cell (PEMFC)● Solid oxide fuel cell (SOFC)● Alkaline fuel cell (AFC)● Phosphoric acid (PAFC)● Molten carbonate (MCFC)

Different Types of Fuel Cells

Applications● Best used where both heat and power are needed● Provide electricity and drinking water for the astronauts● Car engine

Toyota Mirai Mars Flyer

Advantages● Clean energy (no pollution)● Relatively simple maintenance

o No moving parts● Very long operating times● Tolerant of varied temperatures● Can be placed nearly anywhere● Higher efficiency than oil or gasoline

Comparisons

Car Type Chemical Energy => Electrical Energy (% efficient)

Electrical Energy => MechanicalWork(% efficient)

Other Operations (% efficient)

Overall Efficiency (%)

Pure Hydrogen Fuel Cell

80 80 - 64

Gasoline Powered

35 42 - 15

Battery Powered

72 40 90 30 (can be 65)

Disadvantages● Pure hydrogen works best but gas needs to be enriched● Large size and weight● Expensive● Not very durable● Hard to maintain hydration● Infrastructure not available

Roadblocks● Complex chemical process

o Some fuel cells require the molecules traveling through the membrane to have full purity

o Some fuel cells require pumps

● Energy company opposition● Not economically viable yet

o Not efficient enough to replace conventional methods of generating power

Expenses● $55/kWh

Generating Cost● $500B to create hydrogen infrastructure● $4.50 per GGe from natural gas● $6-11per GGe from renewable energy

Target Market● Automobiles● Factories● Cities● Space programs

Fuel cell used by NASA’s Space Shuttle Orbiter

Future● America’s oil dependence will continually increase● Already 1 Billion spent on fuel cell research● Fuel cell cost has dropped by 50 percent since 2006● 7.2 M investment plan● 2015 - Fuel cell cars

Countries using Fuel CellsINTERNATIONAL PARTNERSHIP FOR THE HYDROGEN ECONOMY

● Australia

● Brazil

● Canada

● China

● European Commission

● France

● Germany

● India

● Italy

● Japan

● Korea

● New Zealand

● Norway

● Russian Federation

● Iceland

● United Kingdom

● United States

Payback Period● 3 years● Relatively large initial cost● Consumer price for electricity cut using fuel cells● More power generated than fossil fuel plant

Why are fuel cells not common?

● Building fuel cells is not difficult BUT...

● Inexpensive● Efficient● Reliable● .. that’s difficult

Fun FactElon Musk says cars running on fuel cells are “extremely silly”

Sources Cited● http://www.altenergy.org/renewables/fuel_cells_power.html● http://auto.howstuffworks.com/fuel-efficiency/alternative-fuels/fuel-cell.htm● http://www.fuelcelltoday.com/about-fuel-cells/benefits● http://www.buildings.com/article-details/articleid/12974/title/fuel-cells-for-cle

an-generation-and-short-payback.aspx● http://cleantechnica.com/2014/12/01/fuel-cell-economics-vs-batteries/● http://www.economist.com/topics/fuel-cells