This is actually early
days in this research and the method described is certainly promising. No clue here though as to how promising
yet. It may well solve the hydrogen
production cost problem with water and that is certainly beneficial.
Hydrogen is still not
the most convenient fuel to work with because it difficult to contain although
it can be done. The reason natural gas
is so convenient is that it can be shipped.
In fact, it happens to be a great retainer of hydrogen.
However, we certainly
need this if we can get the performance needed.
Cheaper green energy
storage solution invented by Calgary profs
Chat
over beer generates lower-cost way to make hydrogen from water
By
Emily Chung
A
new discovery by a pair of University of Calgary chemists could make the
large-scale use of wind and solar energy more feasible.
Curtis
Berlinguette and Simon Trudel have invented an environmentally friendly, highly
customizable way to make a key component in a process that stores electricity
by turning water into hydrogen fuel — at a price they say is roughly 1,000
times cheaper than current methods for making that component.
They
published their method this week online in the journal Science Express and are
currently trying to commercialize it through a new spinoff company called
Firewater Fuel Corp.
Wind
and solar energy are considered clean, renewable sources of electricity, but
they have a major drawback — the amount of power they generate at a given time
depends on the amount of wind and sun at that moment. That doesn't necessarily
correlate with the demand for electricity at a given time. Storing the power
for later use is one way to address the mismatch.
Technically,
electricity can already be stored cleanly by converting water into hydrogen and
oxygen through a process called electrolysis, using a device called an
electrolyzer. The stored chemical energy can be reconverted to electricity by
recombining the hydrogen and oxygen in a fuel cell. It's a process similar to
what happens in a battery and can be used in similar applications, including
electric vehicles. However, hydrogen and water are cleaner storage materials
than those used in batteries and fuel cells tend to be more efficient than
batteries in a number of different ways.
'Very
complicated reaction'
Unfortunately,
at a molecular level, breaking water down into oxygen and hydrogen is a
"very complicated reaction" where many different things can happen
over many steps, said Berlinguette. As a result, the reaction is normally too
slow to be of practical use unless you compensate for the slow speed by adding
extra electricity.
Brandt/University
of Calgary)"If you don't have a catalyst, you'll probably need two or
three times as much electricity as you should," Berlinguette said.
Obviously,
that's not very efficient, green or practical. A special type of compound
called a catalyst can speed the reaction up and greatly reduce the amount of
extra energy needed. But up until now, water electrolysis catalysts have been
made of crystals containing rare, expensive toxic metals such as ruthenium and
iridium.
Berlinguette
and Trudel have invented a way to make catalysts that perform just as well as
those expensive catalysts but cost 1,000 times less. The new process also
allows catalysts to be made from relatively non-toxic metal compounds such as
iron oxide, better known as rust.
Infinite
recipes
"Our
method effectively translates to every metal in the periodic table,"
Berlinguette said.
And
because the new process is much more customizable than existing methods for
making this type of catalyst, the recipe can be tweaked to include any
combination of metals in any proportions to get the best possible performance.
That means it may be possible to find a recipe that far outperforms existing,
expensive catalysts.
The
new catalysts and the process to make them are completely different from
existing water electrolysis catalysts because they weren't originally intended
to be used as catalysts. Trudel was studying them because he was interested
in their magnetic properties. One day, he happened to be hanging out after
work with Berlinguette, who was researching a different kind of catalyst.
Generating
hydrogen
About
95 per cent of the hydrogen fuel in North America is produced from natural gas,
according to the U.S. Department of Energy. Producing hydrogen from water is
more expensive — according to the Florida Solar Energy Centre, it is roughly
double the cost of hydrogen from natural gas when electricity is five cents per
kilowatt hour. In Ontario, electricity ranges from 6.3 to 11.8 cents per
kilowatt hour.
"Truthfully,
we were just chatting over a beer and [I] said 'Why don't we take your
materials and see if they work as catalysts?'" Berlinguette recalled.
"And they worked."
Traditional
methods for making water electrolysis catalysts involve sticking an electrode
into a solution containing the metal, causing crystals called metal oxides to
deposit on the electrode. Mixtures of different metals don’t work, Berlinguette
said, because some of them deposit on the electrode more quickly than others,
forming separate layers rather than a uniform mixture that would make for a
useful mixed metal catalyst.
The
new method involves putting the metals in a scaffold of light-sensitive,
non-metallic, carbon-based molecules and dissolving them in a solution.
Different metals can be dissolved in the same solution and mixed evenly. The
electrode is dipped in the solution and the solvent is allowed to evaporate,
causing the catalyst-containing molecules to stick to it. The researchers then
shine a light on the electrode, breaking down the light-sensitive scaffold and
leaving behind just the evenly distributed metal oxides.
These
metal oxides aren't crystals like traditional electrolysis catalysts, but
"amorphous" materials with a less organized structure and gaps called
"defects." The researchers think that is what makes them more
reactive and therefore better catalysts.
According
to the University of Calgary, FireWater Fuel Corp. plans to have a commercial
electrolyzer available by 2014 and a home version on the market a year later.
1 comment:
Fantastic!
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