Published 12:00 am PDT Sunday, August 17, 2008 Story appeared in MAIN NEWS section, Page A9
WASHINGTON – Scouring the Earth for new sources of clean, renewable
energy, scientists and engineers are exploring some unusual nooks and
crannies.
Kites, waves, tides, ocean currents, geysers, garbage,
cow manure, old utility poles, algae and bacteria are being enlisted in
the effort to lower the world's reliance on climate-warming coal and
oil.
Researchers are even trying artificial photosynthesis,
producing electricity by imitating the way that green plants exploit
the sun's energy.
Most of these ideas may never make economic or technological sense.
It's always possible, however, that a daffy-sounding scheme could turn
out to be the next Google, GPS, Facebook or similar breakthrough.
Many
exotic proposals would be expensive, at least at first, and of
uncertain reliability. They mostly depend on government subsidies, and
probably the continued high price of oil, to make them competitive with
the old standbys.
Here are some of the innovative ideas that researchers – and venture capitalists hoping for profit – are working on:
Waves
People
have always been amazed at the enormous power of waves, especially
those pounding the U.S. coastlines. Now they're trying to harness some
of that wasted energy to generate electricity.
The Lisbon, Portugal-based European Wave Energy Centre (www.wave-energy-centre.org) lists 63 such projects with catchy names such as Wave Dragon, WaveRoller, Manchester Bobber and Poseidon's Organ.
Some
use floating devices that bob up and down with the waves. Others try to
capture energy from the surf along beaches. A "wave swing" hanging
below the sea's surface generates electricity from the rising and
falling pressure of waves passing overhead.
"No design has yet
emerged to be the winner," said Chang Mei, an ocean engineering expert
at the Massachusetts Institute of Technology.
Currents
Suitable ocean currents are scarcer but more dependable than waves, Mei said.
An
ambitious scheme being developed at Florida Atlantic University in Boca
Raton would anchor a fleet of turbines to the seafloor under the Gulf
Stream 13 to 15 miles off the east coast of Florida.
The vast,
untapped power of the Gulf Stream would spin the turbines as it flows
north at a steady 5 mph. Underwater cables would carry electricity to
shore. A prototype turbine is being tested in a laboratory before it
goes into the water next year, assuming that questions about the
environment are settled.
Tides
The United Kingdom
is weighing a plan to place a 10-mile-long "barrage," a sort of dam,
across the Severn Estuary between Wales and southwest England. The rise
and fall of the estuary's 48-foot tides would spin turbines, like a
hydroelectric dam, but it would work both ways, as the tide roared in
and out.
The $29 billion tidal-power plan is being fought on
economic and environmental grounds, and its fate is uncertain. A
similar, smaller barrage has been producing energy in France for 40
years.
Wind
Wind turbines have become a common
sight in the United States and Europe, but researchers are exploring
novel sources of wind power.
A German company, Beluga Shipping (www.beluga-group.com),
hooked a 520-square-foot kite to a freighter to help tug it 12,000
miles across the Atlantic last winter. The kite saved 20 percent of the
fuel that's usually used in the crossing, the company said.
An Alameda company, Makani Power (www.makanipower.com),
received a $10 million grant from Google to construct a system of
extremely high-flying kites to exploit the fact that winds are much
stronger and steadier thousands of feet above the ground.
Artificial photosynthesis
A major problem with solar power is how to store the sun's energy at night or on cloudy days.
Now
Daniel Nocera, a chemist at MIT, has found a way to imitate nature's
solution: using plants to turn sunlight into water and carbohydrates,
which then can be turned into energy.
Nocera's invention uses
solar power to split water into hydrogen and oxygen more cheaply and
easily than ever before. The chemicals are stored in fuel cells, which
generate electricity when it's needed.
About the writer:
Call Robert S. Boyd, McClatchy Washington Bureau, (202) 383-6007.
