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.
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.
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.