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Green Energy: Fuel Cell? Solar? Wind? Our Future?. Dr. Hayden So Department of Electrical and Electronic Engineering 3 Oct, 2008. What do we have today?. Global Warming. Carbon Dioxide. … and running out of resources…. Finding Alternative Energy Sources. Solar. Wind. Hydrogen
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Green Energy: Fuel Cell? Solar? Wind? Our Future? Dr. Hayden So Department of Electrical and Electronic Engineering 3 Oct, 2008
What do we have today? Global Warming
Finding Alternative Energy Sources Solar Wind Hydrogen Fuel Cell Clean (Does not pollute) GeoThermal Ethanol Biodiesel Nuclear Fossil Renewable (Naturally Replenished)
Hydrogen Fuel Cell Air/Oxygen flows in other side Hydrogen flows in Catalyst forces H2 to split into electrons and positive ions Polymer Electrolyte Membrane (PEM) only allows positive ions to flow through Negative charges flow externally to form electric current
Fuel Cell in Real World AC Transit (near Berkeley) Honda FCX Clarity BMW Hydrogen 7
Getting Hydrogen Honda Home Energy Station IV
Problems with Hydrogen Fuel Cell Cars • Bulky • Large amount of hydrogen needed for long range • Energy efficiency of producing hydrogen • Not all sources of hydrogen is renewable • May use more energy to generate hydrogen that overcome its benefit • PEM depreciate fast • Not work at temp < 0 or > 100 degree C • Lack of infrastructure • No existing infrastructure to deliver hydrogen economically
Hybrid Technology • Conventional combustion + Electric Engine • Gas: PowerElectric: save gas • Combustion engine turns off automatically when not needed • Electric motor powered by on-board battery • Battery charged during brake/deceleration
Hybrid Vehicles Sale Hybrid Vehicle Sales
Solar Energy • Convert radiation from the Sun into electricity by photovoltaics and other means. • Pros: always available (during day time), renewable, free • Cons: doesn’t work at night, cloudy day, large area • Increase in efficiency recent years: • 17% in 1980s, around 40% in 2007 Helios
Biofuel: Biodiesel and Ethanol • Generate electricity through Biomass • Sugar cane, core, animal manure, etc… • Make biodiesel/ethanol to use in car • Pros: Net carbon neutral (hopefully) • Cons: Food for electricity? Pest?
Just Yesterday • Honda unveils new version of Insight • The first commercially available hybrid vehicle Original Honda Insight, 1999
Summary • We NEED to find alternative Earth-friendly energy sources, NOW • Global warming + high oil price has motivated many innovations in the past 2-3 years • More innovations needed • Huge engineering effort • Do you best to save the world: Take care of Planet Earth. View of the Earth as seen by the Apollo 17