Today, let's throw cold water on the inventive
mind. The University of Houston's College of
Engineering presents this series about the machines
that make our civilization run, and the people
whose ingenuity created them.
Deep in the ocean, 2000 feet
below Keahole Point in Hawaii, the water is cold.
Engineers at the Natural Energy Lab have run a pipe
down to reach it. They bring 25,000 gallons a
minute to the surface, and they do wonderful things
with it.
It may sound strange, but the first thing an
engineer thinks of when he sees all that cold water
is power production. Any heat engine needs a flow
of heat from a hot place to a cold one. Heat
flowing from the 80-degree Pacific sea water into
43-degree water from below can be made to generate
electricity. That's the first thing these engineers
set out to do.
They've built the power plant, but it's been hard.
Normal plants operate between a furnace at
thousands of degrees and a cold condenser. They're
trying to milk energy from less than a 40-degree
difference. They can produce power, but so far it
costs more than energy from cheap oil. It's a
start, and it can be improved. When oil prices
rise, it could be attractive.
Yet, as these engineers worked, that modest
temperature difference tickled their inventive
genius. They saw how it could make food. For
example: now they run cold water pipes through beds
of strawberries and lettuce. The pipes cool them so
they can grow in the warm Hawaii climate. But water
from the air also condenses on the pipes. Then it
drips into the beds and irrigates them.
The engineers also mix the cold water with warm
surface water and use it in lobster farms. The
water is the same temperature -- year around. These
lobsters don't have to hibernate through winter.
They take only half as long to mature.
Possibilities keep tumbling out of that pipe. The
purity of water, so far from surface pollution,
makes it ideal for growing algae to make
pharmaceuticals. And now the lab has taken up fish
farming as well. That water can produce a whole
megawatt of power. They even use it in their air
conditioning.
The creative mind is fed by oddity -- by the thing
out of the ordinary. These Hawaiian engineers,
faced with the oddity of cold water pouring into a
warm place, have feasted upon the image. They've
seen possibility within it. That recognition has
given us lobsters, strawberries, and electricity
where no one would have looked for lobsters,
strawberries, or electricity. These engineers have
plumbed the wealth of their imaginations and found
new wealth in the sea.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
work.
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