Unit 5 Section 12 Hydrogen Power

advertisement
BMW prototype that runs on hydrogen
http://gm-volt.com/2011/12/12/gm-and-bmw-to-collaborate-on-hydrogen-vehicles/
http://phillihp.com/wp-content/uploads/2014/03/hydrogen_fuel_cell_car2.jpg
69. As economies develop and mature, what energy path do
they tend to follow? high carbon/low hydrogen fuels at early
stages to fuels with higher hydrogen and lower carbon
contents
Typically, what are the three stages nations follow in energy
development?
(1) use wood as their main primary fuel at a pre-industrial
stage
(2) shift to coal during industrialization
(3) then transition to oil and natural gas as their economies
mature
Why does this progression takes place?
It takes place because each new fuel is cleaner-burning and
easier to distribute and store than its predecessor
The United States and western Europe are beginning to plan
for perhaps the next stage on the decarbonization path—
hydrogen—but this transition will require several decades to
design and deploy systems for producing, transporting, and
using hydrogen fuel.
Hydrogen powered airplanes
http://www.greendiary.com/bucher-citycat-h2-world-s-first-hydrogen-powered-municipal-vehicle-is-really-clean.html
70. What is sometimes called a "fuel of the future" and
an energy carrier? Hydrogen
Like electricity, pure Hydrogen does not occur naturally in
quantities worth harnessing to meet human energy needs:
the main naturally occurring stocks of hydrogen are tied
up in chemical compounds, most importantly water
molecules (H2O) and hydrocarbons such as coal, oil and
methane (CH4). Stripping hydrogen from hydrocarbon
fuels or obtaining it by splitting water using electricity or
heat is not technically difficult.
What is the problem with obtaining hydrogen?
more electricity or primary-fuel energy is used than the
resulting hydrogen contains
71. What are the benefits of paying this energy
price to get hydrogen?
hydrogen's portability, storability, amenability to
high-efficiency application and low emissions.
One application currently under research is the
use of hydrogen fuel cells to power car.
https://www.llnl.gov/str/June07/Aceves.html
View under the hood of a fuel cell car
http://www.learner.org/courses/envsci/visual/img_lrg/hydrogen_energy.jpg
72. Today, the oil and chemical industries
worldwide use about 50 million tons of hydrogen
each year, most of it extracted from natural gas
and coal. Deriving hydrogen from fossil fuels emits
CO2, so scaling the process up would increase
greenhouse gas emissions unless the associated
carbon were captured and stored
74. Existing fuel cell technologies can convert as much
as 70 percent of hydrogen's energy content to
electricity.
Why are none of the basic designs in use today ready
for mass production?
not cheap and technically simple enough yet for mass
production
Fuel cells have been used for applications such as
producing power on manned space missions
Space shuttle Atlantis
during liftoff.
The space shuttles used
Hydrogen gas fuel cells.
http://cdn.arstechnica.net/wp-content/uploads/2011/07/nasa-shuttle-launch-3_sm2.jpg
75. The transition to a hydrogen economy poses
many challenges. List these.
• it takes seven times as much hydrogen on a
volume basis to produce the same amount of
energy in a gallon of gasoline
• building new energy storage and distribution
systems nationwide
• cars, heating systems, and consumer goods—will
have to be converted
Most expert assessments of the timing for a
hydrogen economy project that such systems will
not start to be deployed on a large scale until
2020 or later, and that making a full transition
from fossil fuels to hydrogen in the United States
would take until approximately 2050 or later.
The Famous Hydrogen
Gas Airship.
Can you name it?
Download