A Potato Battery Can Light Up a Room
For Over a Month (
As one of the most ubiquitous crops in the
world, the potato is poised to feed the entire world. « Along the way, scientists discovered
that the popular staple of many people’s diets may also have potential to help
power it as well.!!
A couple years ago, researchers at the Hebrew
University of Jerusalem released their finding that a potato boiled for
eight minutes can make for a battery that produces ten times the power of a raw
one.!! Using small units comprised of a quarter-slice
of potato sandwiched between a copper cathode and a zinc anode that’s
connected by a wire, agricultural science professor Haim Rabinowitch and his
team wanted to prove that a system that can be used to provide rooms with
LED-powered lighting for as long as 40 days. At around one-tenth the cost of
a typical AA battery, a potato could supply power for cell phone and other personal electronics in
poor, underdeveloped and remote regions without access to a power grid. J
To be clear, the potato is not, in and of itself, an
energy source. What the potato does is simply help conduct electricity by
acting as what’s called a salt-bridge between the two metals, allowing the
electron current to move freely across the wire to create electricity. « Numerous
fruits rich in electrolytes like bananas and strawberries can also form this
chemical reaction.!! They’re basically nature’s version of battery acid.
“Potatoes were chosen because of their
availability all over including the tropics and sub-tropics,” Rabinowitch told
the Science and Development Network.
They are the world’s fourth most abundant food crop.”
But besides being rich in phosphoric acid, spuds are
ideal in that they’re composed of sturdy starch tissue, can be stored for
months and won’t attract insects the way, say strawberries, would.
Additionally, boiling the potato breaks down the resistance inherent in the
dense flesh so that electrons can flow more freely, which significantly bumps
up the overall electrical output. Cutting the potato up into four or five
pieces, they researchers found, made it even more efficient. O
The potato battery kit, which includes two metal
electrodes and alligator clips, is easy to assemble and, some parts, such as
the zinc cathode, can be inexpensively replaced. The finished device
Rabinowitch came up with is designed so that a new boiled potato slice can
be inserted in between the electrodes after the potato runs out of juice.
Alligator clips that transport the current carrying wires are attached to the
electrodes and the negative and positive input points of the light bulb.
Compared to kerosene lamps used in many developing parts of the world, the
system can provide equivalent lighting at one-sixth the cost; it’s estimated to
be somewhere around $9 per kilowatt hour and a D cell battery, for
another point of comparison, can run as much as $84 per kilowatt hour.!! O
Despite the advantages, a recent BBC report that
followed up on the group’s initial discovery found that the group has since
been beset with a number of extenuating circumstances that have hindered their
efforts to scale up their idea to places like villages in off-the-grid parts in
Africa and India. L $ Economically speaking,
food-based energy systems can only be viable as long as they don’t eat into the
needed food supply and that such enterprises don’t compete with farmers who
grow them for market. The technology is also having a difficult time
establishing a niche among more fashionable forms of alternative energy like solar and wind power,
where infrastructure and investment seems to be headed mostly. L Thus far, no commercial
investors or non-profit organization has stepped up to help expand or
distribute any of the prototypes Rabinowitch has developed.
To really make an impact, perhaps the potato
needs to stop being so humble. $
Answer W-questions about a potato battery can
light up a room for over a month.
1.
Who?
Agricultural science professor Haim
Rabinowitch and his team.
2.
What?
A potato could supply power.
3.
Where?
The Hebrew University of Jerusalem
4.
Why?
They
wanted
to prove that a system that can be used to provide rooms with LED-powered
lighting for as long as 40 days.
5.
When?
A couple years ago.
6.
How?
Rabinowitch
came up with is designed so that a new boiled potato slice can be inserted
in between the electrodes after the potato runs out of juice. Alligator clips
that transport the current carrying wires are attached to the electrodes and
the negative and positive input points of the light bulb. Compared to kerosene
lamps used in many developing parts of the world, the system can provide
equivalent lighting at one-sixth the cost; it’s estimated to be somewhere
around $9 per kilowatt hour and a D cell battery, for another point
of comparison
