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Shipload of rubbish
boat that was built entirely from recycled
plastic bottles and other bits of
A
rubbish, including old advertising banners,
has set sail in Taiwan to raise awareness of
the marine environment there.
The trimaran, named Polli-Boat, has a
main flotation system that uses a series of
interlocking plastic bricks made from recycled
plastic bottles and is strengthened using
polyethylene terephthalate (PET), the most
common plastic in use today.
The seven metre boat has a flotation pontoon
made from 804 of these plastic bricks
that, once locked together, allow it withstand
the pressures caused when sailing.
According to Arthur Huang, the founder
and managing director of Miniwiz Sustainable
Energy Development, the trimaran is
powered by wind as well as solar energy to
run a small engine and keep various instruments
on board operating smoothly. It has
six solar panels on deck and each panel is
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Watt’s Science
capable of producing 72W for the electric
motor used by the boat when there is no wind
around or to help it moor in the harbour.
The boat is set to tour the whole of Taiwan
and is one of the competitors in a friendly
creative boat competition being held throughout
the country. It has been sponsored by the
National Geographic Channel of Taiwan who
paid for contestants to build ten of the boats
– from more than 200 entries – that were
submitted to it. One of the novel ideas was a
vessel built in the shape of an endangered
black-faced spoonbill.
This boat is aimed at promoting
wetlands protection.
Microbes power a light bulb
Scientists may start using microbes to
generate electricity after discovering
how they let off tiny electrical charges. The
bacteria were found to contain microscopic
‘wires’ that stick through the cell walls.
These microbes might also be used to clean
or spills or curb uranium pollution.
According to scientist Tom Clarke of the
University of East Anglia in England the
discovery of the exact structure of the bacteria
and their atom-sized wires would allow
researchers to design electrodes with better
contacts to pick up the charges let off by
microbes to avoid a build-up of electricity.
Clarke says this would mean that electricity
could be harvested from bacteria. He says
that until now it has been a bit like trying
to build a radio when you do not know what
type or size of battery you will use.
Now, he says, the scientific community has
a blueprint for the wiring of the bacteria.
Every living creature uses electricity: in humans,
for instance, electricity keeps hearts
pumping and brains thinking. The bacteria
use their wires to discharge excess electricity.
“If they get a build-up of charge then
everything else stops, from feeding to respiration,“
he says.
Clarke believes that it could take up to ten
years to develop and use the bacteria that
are of a type called Shewanella oneidensis.
These bacteria would be able to live in an
oxygen-free environment and could be used
as a power source for everything from light
bulbs to mobile phone chargers. He says that
existing uses of such bacteria would have to
become about a hundred or possibly a thousands
times more efficient than they currently
are.
However, Clarke says that the findings
could help to speed-up development of microbe-based
agents that could be used to
clean up oil spills, or in fuel cells that are
powered by sewage or compost.
Clarke points out these bacteria do not
need energy-rich fuels to thrive as they can
survive inside an oil slick or even degrade
used oil and produce energy at the same
time. He says that bacteria could be used
in nuclear plants to separate uranium from
waste water and could be useful in helping
to clean up after an accident like the one
that occurred at Japan’s Fukushima Daiichi
plant earlier this year.
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