Hydrogen exists in fossil fuels, alcohols,
even in water. Today, common ways of producing hydrogen
include reforming natural gas in which four hydrogen
atoms are separated from a carbon
atom, and
electrolyzing water which de-couples two hydrogen atoms from an oxygen
atom. The fact that hydrogen can be produced in so many
ways means that, unlike petroleum, supplies of hydrogen
cannot run out, nor will they be concentrated in one area
of the world.
Hydrogen is everywhere and just needs to be
captured and used.
Capturing hydrogen, however, is not as easy as it
sounds. There isn't much pure hydrogen around because
hydrogen tends to bond easily with other elements. To
make hydrogen fuel, hydrogen must be separated from
whatever it's attached to, a process which requires
energy. For this reason, hydrogen is often called an
energy carrier rather than an energy source. To get
hydrogen, you first have to put energy in. For example,
making a kilogram of hydrogen from
water
through
electrolysis requires 45-70 kWh of electricity,
depending on the technology.
This amount of electricity could power the average
American home for roughly 2-3 days.
2. Hydrogen fuel produces no emissions.
Assume that you are producing
hydrogen through
electrolysis (by using electricity to
separate hydrogen atoms from oxygen atoms.) Depending on
where that electricity comes from, hydrogen can be clean
and efficient, or anything but.
In many areas of the country, electricity comes
primarily from coal-fired power plants. Burning coal to
generate electricity, and then using that electricity to
make hydrogen is not an environmentally friendly idea. The hydrogen at
the end of the process may be used in vehicles that are
"clean," but the coal used to make the
electricity emitted significant amounts of pollution and
greenhouse gases. In addition, this process is not very
efficient since losses occur each time one form of
energy is converted to another.
However, if the electricity used to make hydrogen comes
from renewable sources, such as hydro-electric,
geothermal, solar or wind, then hydrogen can be
extremely clean. Hydrogen from renewable sources also
releases no climate change emissions, and provides users
with complete independence from fossil fuels. This is
what appeals to hydrogen supporters. The prospect of a fuel that is plentiful, non-polluting, and safe for the
world's climate.
3. The hydrogen highway is under construction and will
be opening soon (?)
According to the Department of Energy, there are just 15-hydrogen
stations in the U.S., and 10 are in
California. Hydrogen is hard to store onboard a vehicle,
and it's also hard to store in tanker trucks, rail cars,
and other equipment traditionally used to distribute
liquid fuels. So we'll probably need to re-evaluate our fuel
distribution infrastructure in order to supply hydrogen
more effectively.
One advantage of hydrogen is that it can be made on-site
at fueling stations, or in homes using electrolyzers or natural gas reformers.
So in the future, hydrogen may give consumers more
choice in locations to fuel their vehicles. However, hydrogen infrastructure will
take significant amounts of time and financial
investment to develop, and many buyers will not want a
hydrogen-powered vehicle until the refueling network is
in place. Hydrogen has great promise as a future
automobile fuel. If
hydrogen is made using environmentally sound methods and
used in highly efficient fuel-cell vehicles, then the
fuel offers a real solution to the problems of urban
smog and climate change, not to mention the rising cost
of gasoline. However, much of the technology
we need to make safe hydrogen vehicles a reality does not
exist yet. Hydrogen is a future solution, and we should
be careful not to focus exclusively on hydrogen at the
expense of other solutions that can be implemented
sooner.
