Hydrogen Fuel Cell
Scientists are also exploring the use of hydrogen gas as a renewable
energy source. Hydrogen is the simplest atom, made up of one
proton—the nucleus—and one electron. Scientists have found ways
to separate hydrogen from water and from fossil fuels. It is a
flammable gas and must be handled with care.
Hydrogen is used in a a device that produces
electricity by separating hydrogen into protons and electrons. The
diagram below shows hydrogen fuel entering on one side of the
cell while oxygen from the air enters on the other side. Once in the cell,
electrons flow out of the cell through wires, forming an electric current
that powers the motor. The protons pass through a membrane and
combine with oxygen to form water as a byproduct.
Hydrogen fuel cells are used to supply electrical energy on spacecraft and space stations. Fuel-cell buses are being
tested in several countries.
Also, some fuel-cell cars are now available to the public. Storage tanks in these vehicles carry hydrogen fuel for the
cells. Fuel-cell technology holds great promise for the future. Hydrogen
is a clean source of energy, producing only water and heat as byproducts.
If every vehicle in the world were powered by hydrogen, the level of air pollution would drop sharply.
However, hydrogen fuel cells are still too expensive to produce in large numbers. Separating hydrogen from water or
from fossil fuels takes a great deal of energy, time, and money. Also, there are only a few
fueling stations to supply cars and other vehicles that run on hydrogen.
The U.S. Department of Energy is working with the automotive industry and other industries to solve these problems.
Hydrogen Fuel Cell vehicles use hydrogen gas to power an electric motor. Unlike conventional vehicles which run on
gasoline or diesel, fuel cell cars and trucks combine hydrogen and oxygen to produce electricity, which runs a motor.
Since they’re powered entirely by electricity, fuel cell vehicles are considered electric vehicles (“EVs”)—but unlike
other EVs, their range and refueling processes are comparable to conventional cars and trucks.
Converting hydrogen gas into electricity produces only water and heat as a byproduct, meaning fuel cell vehicles don’t
create tailpipe pollution when they’re
driven.
Because fuel cell vehicles are only
beginning to enter the U.S. market,
interested drivers should ensure they
live near hydrogen refueling stations.
One advantage of hydrogen fuel cell
vehicles is that they can be refueled at a
filling station in a short time. This
means that drivers who would rather not
plug in a battery electric car can still use
a clean electric motor to get around. The
filling time is about the same as a
gasoline vehicle, about 5-10 minutes for
a 300-mile range.
Of course, to take advantage of a hydrogen car, the filling stations need to be available. California is building the first
wave of hydrogen filling stations with 28 currently operational or under construction and 68 planned for use by
2016. Starting in the Los Angeles and San Francisco metro areas, these stations are designed to fuel the first 20,000
fuel cell vehicles.
List of Advantages of Hydrogen Fuel Cells
1. It is readily available.
As mentioned earlier, hydrogen is a basic earth element and it’s very abundant. However, it takes a whole lot of time to
separate hydrogen gas from its companion substances. While that may be the case, the results produce a powerful clean
energy source.
2. It doesn’t produce harmful emissions.
When hydrogen is burned, it doesn’t emit harmful substances. Basically, it reacts to oxygen without burning and the
energy it releases can be used to generate electricity used to drive an electric motor. Also, it doesn’t generate carbon
dioxide when burnt, not unlike other power sources.
3. It is environmentally friendly.
Hydrogen is a non-toxic substance which is rare for a fuel source. Others such as nuclear energy, coal and gasoline are
either toxic or found in places that have hazardous environments. Because hydrogen is friendly towards the
environment, it can be used in ways that other fuels can’t even possibly match.
4. It can be used as fuel in rockets.
Hydrogen is both powerful and efficient. It is enough to provide power for powerful machines such as spaceships.
Also, given that it is environmentally friendly, it is a much safer choice compared to other fuel sources. A fun fact:
hydrogen is three times as powerful as gasoline and other fossil fuels. This means that it can accomplish more with
less.
5. It is fuel efficient.
Compared to diesel or gas, hydrogen is much more fuel efficient as it can produce more energy per pound of fuel. This
means that if a car is fueled by hydrogen, it can go farther than a vehicle loaded with the same amount of fuel but using
a more traditional source of energy.
Hydrogen-powered fuel cells have two or three times the efficiency of traditional combustion technologies. For
example, a conventional combustion-based power plant usually generates electricity between 33 to 35 percent
efficiency. Hydrogen fuel cells are capable of generating electricity of up to 65 percent efficiency.
Also, a gasoline-powered engine in a conventional car is not as efficient as converting chemical energy into gasoline
into power that moves vehicles under normal driving conditions. With vehicles that use hydrogen fuel cells, and also
use electric motors, are more efficient as they can use 40 to 60 percent of the fuel’s energy. As a result, there is more
than 50% reduction in fuel consumption.
Plus, fuel cells operate quietly, have fewer moving parts and are well-suited for various kinds of applications.
6. It is renewable.
Hydrogen can be produced again and again, unlike other non-renewable sources of energy. This means that with
hydrogen, you get a fuel source that is limited. Basically, hydrogen energy can be produced on demand. Also, it is
widely available – all that is needed is to break the water molecules so it gets separated from oxygen. It’s without
question a time consuming process but the outcome is great.
List of Disadvantages of Hydrogen Fuel Cells
1. It is expensive.
While widely available, hydrogen is expensive. A good reason for this is that it takes a lot of time to separate the
element from others. If the process were really simple, then a lot would have been doing it with relative ease, but it’s
not.
Although, hydrogen cells are now being used to power hybrid cars, it’s still not a feasible source of fuel for everyone.
Until technology is developed that can make the whole process a lot simpler, then hydrogen energy will continue to be
an expensive option.
2. It is difficult to store.
Hydrogen is very hard to move around. When speaking about oil, that element can be sent though pipelines. When
discussing coal, that can be easily carried off on the back of trucks. When talking about hydrogen, just moving even
small amounts is a very expensive matter. For that reason alone, the transport and storage of such a substance is
deemed impractical.
3. It is not easy to replace exiting infrastructure.
Gasoline is still being widely used to this day. And as of the moment, there just isn’t any infrastructure that can support
hydrogen as fuel. This is why it becomes highly expensive to just think about replacing gasoline. Also, cars need to be
refitted in order to accommodate hydrogen as fuel.
4. It is highly flammable.
Since it is a very powerful source of fuel, hydrogen can be very flammable. In fact, it is on the news frequently for its
many number of risks. Hydrogen gas burns in air at very wide concentrations – between 4 and 75 percent.
5. It is dependent on fossil fuels.
Although hydrogen energy is renewable and has minimal environmental impact, other non-renewable sources such as
coal, oil and natural gas are needed to separate it from oxygen. While the point of switching to hydrogen is to get rid of
using fossil fuels, they are still needed to produce hydrogen fuel.