Transcript Hydrogen as Fuel

Automotive Uses
Hydrogen
 Hydrogen is the lightest and most abundant chemical
element
 Naturally occurring elemental hydrogen is relatively
rare on Earth
 At standard temperature and pressure, hydrogen is a
colorless, odorless, nonmetallic, tasteless, highly
combustible gas with the molecular formula H2
Hydrogen Production
 Industrial production is mainly from the steam
reforming of natural gas
 In steam-methane reforming, methane reacts with
steam under 3–25 bar pressure (1 bar = 14.5 psi) in the
presence of a catalyst (nickel) to produce hydrogen,
carbon monoxide, and a relatively small amount of
carbon dioxide
 Methane:
CH4 + H2O (+heat) → CO + 3H2
Hydrogen Production cont.
 Electrolysis
 An electrical power source is connected to two
electrodes, or two plates (typically made from some
inert metal such as platinum or stainless steel) which are
placed in the water.
 In a properly designed cell, hydrogen will appear at the
cathode (the negatively charged electrode, where
electrons enter the water), and oxygen will appear at the
anode (the positively charged electrode).
Hydrogen Production cont.
 Currently It costs about $2.50 just to produce 1 Kg of Hydrogen.
 Delivery and storage is difficult and expensive
 Virtually no H2 infrastructure exists.
Energy Content
 Assuming equal weights H2 contains approximately 3
times the energy of gasoline.
 1 Kilogram (2.2 lbs.) of H2 is considered roughly
equivalent to 1 gallon of gasoline (approx. 6lbs.)
Emissions
 When burned in an internal combustion engine
Hydrogen will create temperatures high enough to
create Oxides of Nitrogen (NOx) gasses.
 The NOx gasses are less than those emitted by current
Near Zero emission vehicles.
 Other typical automotive emissions are essentially
non-existent from Hydrogen burning vehicles
Emissions cont.
 Currently –
 The production of 1 Kg of H2 develops as much
pollution as a standard automobile
Hydrogen Storage
 A gram of hydrogen gas occupies about 11 liters (2.9
gallons) of space at atmospheric pressure (14.7 psi)
 Remember that 1 Kg of H2 has the same energy as 1
gallon of gasoline.
 So, at atmospheric pressure,
2900 gallons of H2 is needed to equal the energy content of one
gallon of gasoline.
Hydrogen Storage cont.
 The gas must be intensely pressurized to several
hundred atmospheres and stored in a special tank.
OR
 In liquid form, hydrogen can only be stored under
cryogenic temperatures.
 -423 degrees F
OR
Hydrogen Storage cont.
 Storage of hydrogen in hydride form.
 This method uses an alloy that can absorb and hold
large amounts of hydrogen by bonding with hydrogen
and forming hydrides.
 A hydrogen storage alloy is capable of absorbing and
releasing hydrogen without compromising its own
structure.
 Currently only viable for small scale use.
BMW H2R Hydrogen Car
 Basically the same engine used in the carmaker's 760i
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luxury sedans
Running on hydrogen, it develops 286 horsepower
Zero to 60 mph in under six seconds
187 mph top speed
Bi-Fuel
 Gasoline or H2 at the push of a button
BMW H2R Hydrogen Car cont.
 Use liquid hydrogen
 Must be kept very cold, below -423F.
 The car's onboard cryogenic system takes care of this
automatically
 If the vehicle isn't started up for three or four days, the
liquid will begin to boil, and hydrogen gas will escape
through a vent.
 Hydrogen is less dangerous than gasoline. It disperses
quickly, so even when a container leaks explosions are
next to impossible.
Hydrogen as a Supplement
 HHO, or Brown Gas, generators are quite popular on
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the web.
These small scale generators produce enough H2 to act
as a supplemental fuel in gasoline powered cars.
Most use hydrolysis produced through
battery/alternator voltage.
H2 is pumped directly into the intake ducting before
the throttle plate.
How effective is this?
Assignment
 Given the equipment available here at HVCC, and your
knowledge of fuel systems and computer controls, how
can we test the impact of adding H2 to the intake
stream?
 Develop a test procedure and bring it to our next lab
session.