[Offtopic] Five Technologies That Could Change Everything
stephen at melbpc.org.au
stephen at melbpc.org.au
Mon Oct 19 17:04:03 EST 2009
Five Technologies That Could Change Everything
OCTOBER 19, 2009 The Wall Street Journal Cover Story By MICHAEL TOTTY
It's a tall order: Over the next few decades, the world will need to wean
itself from dependence on fossil fuels and drastically reduce greenhouse
gases. Current technology will take us only so far; major breakthroughs
What might those breakthroughs be? Here's a look at five technologies
that, if successful, could radically change the world energy picture.
They present enormous opportunities. The ability to tap power from space,
for instance, could jump-start whole new industries. Technology that can
trap and store carbon dioxide from coal-fired plants would rejuvenate
Success isn't assured, of course. The technologies present difficult
engineering challenges, and some require big scientific leaps in lab-
created materials or genetically modified plants. And innovations have to
be delivered at a cost that doesn't make energy much more expensive. If
all of that can be done, any one of these technologies could be a game-
SPACE-BASED SOLAR POWER
For more than three decades, visionaries have imagined tapping solar
power where the sun always shinesin space. If we could place giant solar
panels in orbit around the Earth, and beam even a fraction of the
available energy back to Earth, they could deliver nonstop electricity to
any place on the planet.
The technology may sound like science fiction, but it's simple: Solar
panels in orbit about 22,000 miles up beam energy in the form of
microwaves to earth, where it's turned into electricity and plugged into
the grid. (The low-powered beams are considered safe.) A ground receiving
station a mile in diameter could deliver about 1,000 megawattsenough to
power on average about 1,000 U.S. homes.
The cost of sending solar collectors into space is the biggest obstacle,
so it's necessary to design a system lightweight enough to require only a
few launches. A handful of countries and companies aim to deliver space-
based power as early as a decade from now.
ADVANCED CAR BATTERIES
Electrifying vehicles could slash petroleum use and help clean the air
(if electric power shifts to low-carbon fuels like wind or nuclear). But
it's going to take better batteries.
Lithium-ion batteries, common in laptops, are favored for next-generation
plug-in hybrids and electric vehicles. They're more powerful than other
auto batteries, but they're expensive and still don't go far on a charge;
the Chevy Volt, a plug-in hybrid coming next year, can run about 40 miles
on batteries alone. Ideally, electric cars will get closer to 400 miles
on a charge. While improvements are possible, lithium-ion's potential is
One alternative, lithium-air, promises 10 times the performance of
lithium-ion batteries and could deliver about the same amount of energy,
pound for pound, as gasoline. A lithium-air battery pulls oxygen from the
air for its charge, so the device can be smaller and more lightweight. A
handful of labs are working on the technology, but scientists think that
without a breakthrough they could be a decade away from
Everybody's rooting for wind and solar power. How could you not? But wind
and solar are use-it-or-lose-it resources. To make any kind of
difference, they need better storage.
Scientists are attacking the problem from a host of anglesall of which
are still problematic. One, for instance, uses power produced when the
wind is blowing to compress air in underground chambers; the air is fed
into gas-fired turbines to make them run more efficiently. One of the
obstacles: finding big, usable, underground caverns.
Similarly, giant batteries can absorb wind energy for later use, but some
existing technologies are expensive, and others aren't very efficient.
While researchers are looking at new materials to improve performance,
giant technical leaps aren't likely.
Lithium-ion technology may hold the greatest promise for grid storage,
where it doesn't have as many limitations as for autos. As performance
improves and prices come down, utilities could distribute small, powerful
lithium-ion batteries around the edge of the grid, closer to customers.
There, they could store excess power from renewables and help smooth
small fluctuations in power, making the grid more efficient and reducing
the need for backup fossil-fuel plants. And utilities can piggy-back on
research efforts for vehicle batteries.
CARBON CAPTURE AND STORAGE
Keeping coal as an abundant source of power means slashing the amount of
carbon dioxide it produces. That could mean new, more efficient power
plants. But trapping C02 from existing plantsabout two billion tons a
yearwould be the real game-changer.
Techniques for modest-scale CO2 capture exist, but applying them to big
power plants would reduce the plants' output by a third and double the
cost of producing power. So scientists are looking into experimental
technologies that could cut emissions by 90% while limiting cost
Nearly all are in the early stages, and it's too early to tell which
method will win out. One promising technique burns coal and purified
oxygen in the form of a metal oxide, rather than air; this produces an
easier-to-capture concentrated stream of CO2 with little loss of plant
efficiency. The technology has been demonstrated in small-scale pilots,
and will be tried in a one-megawatt test plant next year. But it might
not be ready for commercial use until 2020.
One way to wean ourselves from oil is to come up with renewable sources
of transportation fuel. That means a new generation of biofuels made from
Researchers are devising ways to turn lumber and crop wastes, garbage and
inedible perennials like switchgrass into competitively priced fuels. But
the most promising next-generation biofuel comes from algae.
Algae grow fast, consume carbon dioxide and can generate more than 5,000
gallons a year per acre of biofuel, compared with 350 gallons a year for
corn-based ethanol. Algae-based fuel can be added directly into existing
refining and distribution systems; in theory, the U.S. could produce
enough of it to meet all of the nation's transportation needs.
But it's early. Dozens of companies have begun pilot projects and small-
scale production. But producing algae biofuels in quantity means finding
reliable sources of inexpensive nutrients and water, managing pathogens
that could reduce yield, and developing and cultivating the most
productive algae strains.
Mr. Totty is a news editor for The Journal Report in San Francisco. He
can be reached at michael.totty at wsj.com Printed in The WSJ, page R2
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