An Overview of Hydrogen Power
description
Transcript of An Overview of Hydrogen Power
The Energy Center
Hydrogen and Future US Energy Supplies
Prof. Mahdi Abu-Omar
Chemistry Department
CoBank 2008 Energy and Water Executive ForumAugust 12, 2008
The Energy Center
Global Energy Consumption
0
5
10
15
20
25
30
35
40
Oil Coal Gas Nuclear HydroRenew
% G
loba
l prim
ary
ener
gy
con
sum
ptio
n
The Energy Center
The Energy Center
Climate Change
Annual CO2 release
petroleumnatural gascoalhuman
Source: Carbon Dioxide Info Analysis Center
The Energy Center
Planes, Trains, & Automobiles
The Energy Center
US Energy Flow
The Energy Center
Major oil trade movements
BP Statistical Review of World Energy 2007
The Energy Center
US Oil Imports in 2006
Country/Region Million tons Percent (%)
Central & South America 133.1 20.5
Middle East 113.2 17.5
Canada 113.6 17.5
Mexico 84.4 13.0
Norway 54.0 8.3
Africa 131.5 20.3
Old Russia 17.9 2.8
Total 647.7 100
The Energy Center
Need to produce liquid fuel
Renewable & Sustainable
Biofuels• Administration sets
renewable motor vehicle (liquid) fuel goal to 7.5 billion gal by 2012.
• In 2006, the U.S. produced 4.1 billion gal of bioethanol: 2% of gasoline use and 1/6 of corn crop.
• All of Texas (262,000 square miles) needs to be planted with corn to provide ca. 40% of our transportation fuel need!
Source: C&E News April 16, 2007, p. 34.
The Energy Center
C
H
H
O2O C O H
O
H
A Fuel
Carbon dioxideH H
The Energy Center
The Element Hydrogen
The Energy Center
H2 & Its Abundance• Physical Properties:
– Density = 0.0899 g/L (cf. water = 1000 g/L)
– Boiling point = -423 °F (-253 ° C)
– Melting point = -434 ° F (-259 ° C)
– Coldest temp in Antarctica (7/21/1983) = -129 ° F (-89 ° C)
– Flash point = -423 ° F
• Abundance:– Most abundant element in the known
Universe.
– 7th in the Earth’s crust & 3rd in organisms.
The Energy Center
Forms of Hydrogen on Earth
• Not as hydrogen (H2) gas.
• Lots and lots in compounds:– Water H2O
– Natural gas CH4
– Gasoline -(CH2)n-
– Ammonia NH3
– Biomass
The Energy Center
Challenges
SourceUtilization
SafetyStorage
RenewableNoncarbon
Solid stateChemical
Fuel Cell
The Energy Center
Safety is Important
Hindenburg at Lakehurst, NY on 5/6/1937
Iron oxide & aluminum paint!
The Energy Center
The Hydrogen Economy: Fiction or Science?
• President Bush has made the development of a hydrogen economy a major priority. (June 2003, www.whitehouse.gov)
• Providing a cleaner and more secure energy future through hydrogen fuel technology. (President Bush’s technology agenda, June 2004).
Our economy already uses/relies on hydrogen tremendously!!
The Energy Center
Best Source of Hydrogen
CH4 + H2O CO + 3H2
H2O
CO2 + H2
N2Ammonia (NH3)
CO2
Urea
fertilizersmedicines
explosives
syn gas
methanol
DME
diesel
19 million tons per year in the U.S. alone
The Energy Center
Challenges
SourceUtilization
SafetyStorage
RenewableNoncarbon
Solid stateChemical
Fuel Cell
Conclusion
• We are all going to DIE!
There is hope!• [Genesis]: “(1) In the
beginning God created the heavens and the earth. (2) Now the earth was formless and empty, darkness was over the surface of the deep, and the Spirit of God was hovering over the waters.
• (3) And God said, "Let there be light," and there was light. (4) God saw that the light was good, and He separated the light from the darkness.”
14 TW/yearEnergy from sunlight in 1 hour1.76 x 105 TW/year
Solar Conversion to Fuel
Light
Photosynthesis
Fuels Electricity
Photovoltaics
H O
O H
2
22
Sc & Cat. M
eCO
Sugar
H O
O
2
2
2
Semiconductor/Catalyst
sc
e
M
Heat
The Energy Center
NuclearSolar
Wind
H2O
Biomass
Fossil fuel
Natural gas
Coal
H2
Production Storage
H2
Fuel Cells(Automotive)
Electronics
Stationary(electricity/heat)
Use
The Energy Center
Water is the Ultimate Source
air Fuel
Oxygen Hydrogen Water
O 2HO2H 222
• Electrolysis ($?)• Chemical splitting• Solar & bioinspired
I2 + SO2 + 2H2O 2HI + H2SO4
2HI I2 + H2
2H2SO4 2SO2 + 2H2O + O2
The Energy Center
NuclearSolar
Wind
H2O
Biomass
Fossil fuel
Natural gas
Coal
Sources
Novel chemistry that makepolluting sources green
24 2H C CH
Natural gas
The Energy Center
Challenges
SourceUtilization
SafetyStorage
RenewableNoncarbon
Solid stateChemical
Fuel Cell
The Energy Center
A BIG Challenge• Density of H2 = 0.0899 g/L
(cf. water = 1000 g/L).• Towing a football field is not
practical!• Hydrogen pipeline?• High pressure!!
5000 – 10,000 psi
The Energy Center
DOE Road Map
Solar
H2O
Biomass
H2
StorageThe Big Challenge
Liquid Fuel
Need to produce liquid fuel
CO2
The Energy Center
Challenges
SourceUtilization
SafetyStorage
RenewableNoncarbon
Solid stateChemical
Fuel Cell
The Energy Center
Utilizing Hydrogen as a Fuel
• 2H2 + O2 → 2H2O
• Isooctane (C8H18) + O2 → CO2 + H2O
• Combustion of hydrogen is not efficient.
• Fuel Cell technology:– PEM (Proton Exchange
Membrane)
Nafion 100W-500kW
70-120 °C 30-50% (system)
The Energy Center
Fuel Cell Stack
GM Equinox designed to last 50,000 miles
The Energy Center
Research in Fuel CellsFuel Cell Cost Membrane
CatalystGas diffusion layerElectrodes
41%
• Catalyst is expensive!– 180 g Pt in ~150 kW
• Can we learn from nature and devise cheap catalysts?• Membrane research to manage water.
The Energy Center
Present & Future ProspectsHonda’s Hydrogen Home Energy Station (2005)
Uses natural gas (CH4) Mini reformer station Some storage capacity
The Energy Center
CIS Tower in Manchester
In Hong Kong
The Energy Center
Photosynthesis
Electricity
H O
O H
2
22
Sc & Cat. M
e
sc M
H2
CO2
orbiomass
Liquid Fuel
C
H
H
The Energy Center