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Spectron telescope of hydrogen in the Orion Nebula |
If we apply a perversion of Occam's razor to the problem of
global warning made worse by increasing demands for energy, we are left with the
simplest of fuels – natures most abundant and simplest element – hydrogen. All
of the burning of fossil fuels is really a way to burn hydrogen. But using hydrocarbons
burns the hydrogen while producing large amounts of CO2. What if we could burn
the hydrogen in its pure form? It turns out we can. And the byproduct is simply
water. We have been doing it since fuel cells were first invented back in 1839
by Sir William Grove. It's such a good idea that NASA has been using
it for years to provide both water and power on space missions.
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Schematic of a fuel cell showing H on one side of the cell, and water on the other |
A fuel cell is a device consisting of a gas diffusion
electrode comprising a catalyst that separates hydrogen atoms into their
component parts, a proton and an electron. The protons traverse an exchange
membrane and travel through another diffusion electrode, while the electrons
are used to power something. In the above illustration, they power a light
bulb, while in a car they power an electric motor. After this they are reunited
into hydrogen atoms, which combine with the oxygen in the air to produce water. All
that is needed for this to happen is a continuous supply of hydrogen gas.
Boeing has a drone that is powered by a fuel cell with hydrogen produced by a solar array that electrolyzes water. The
California Fuel Cell Cooperative has even
established hydrogen refueling stations to service cars that are powered by
fuel cells.
Maine has an economic
and environmental interest in the hydrogen economy. At
The Hydrogen Energy Center
in
Portland, ME,
in addition to hydrogen and fuel cell
applications for transportation, they are exploring hydrogen as a storage
medium for intermittent energy sources, hydrogen fuel cells for combined heat
and power, and hydrogen applications in the pulp and paper industry. According
to their web site, "When a renewable, economically viable production
process of hydrogen can be achieved the advantages will spread out to many
industries. Some of the proving grounds for various production methods can be
locally developed to provide hydrogen for these industries."
The difficulty all along has been the technology required to
obtain and store hydrogen.
Current methods rely on electrolysis of water which
separates the water into its two components, hydrogen and oxygen. While Elon
musk, the founder of
Tesla, an
electric car company, has put down the concept of hydrogen in favor of his
electric, battery-powered cars, those cars are charged with electricity
produced by carbon based fuels.
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Tesla Motor Company's Tesla 2X |
If this exciting hydrogen-as-fuel concept becomes
widespread, that problem will be eliminated because large hydrogen burning
power plants will replace the current hydrocarbon-based approach. This means
that electric cars can be more efficiently charged using electricity produced
by hydrogen-based power plants. Still, recharging takes a significant amount of
time. Eventually, motors in today's electric cars may be powered
by fuel cells. In either case one of the least desirable aspects of living in
large cities, toxic smog, will be eliminated. If all the vehicles and all the
heating plants in large metropolitan areas were burning hydrogen, there would
be virtually no pollutants in the air. The byproduct of burning hydrogen is
simply water. The byproduct of separating water from the hydrogen is extra
oxygen either being stored for commercial use or simply released into the
atmosphere.
Recent breakthroughs involving catalysts and very small
amounts of electricity are yielding exciting results. There is even a plastic
credit-card-like substance that, immersed in water and exposed to sunlight, causes this breakdown of water into its constituent elements. It's called
an
artificial
leaf.
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Testing a 1 cm x 1 cm artificial leaf. |
This is an exciting prospect because it has the potential for
providing small home sized power systems in
Third World
countries as well as in developing nations, without the dangerous burning of
carbon-based fuel. It even produces
potable water.
Many aspects of the future use of hydrogen as fuel are
already in place. Many are being developed. All are on a fast track to reality,
along with as yet undiscovered and unexplored means of making and storing this
amazing and useful element. A good thing, too, because, while Elon Musk may be
wrong about hydrogen as fuel for cars, he's right about the need for responsible
uses of our planet's resources. If we do nothing, we're headed for disaster.
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