CHEMIST TO SOLVE WORLD ENERGY WOES ?

[Anonymous]

Chemist Tries to Solve World’s Energy Woes

CAMBRIDGE, Mass. (Aug. 05) – Daniel Nocera arrives at his
office at the Massachusetts Institute of Technology by 7 a.m., goes home 13
hours later – where he often reads papers or e-mails students much of the night
– and returns to his labs on weekends. Vacations? None, really, unless you count
chemistry conferences. After all, trying to save the world is hard work.

If you ever wonder about how the world will produce enough
energy to supply 9 billion people by mid-century – and whether that can be done
without pumping off-the-charts amounts of carbon dioxide into the air – meet one
of the minds trying to produce an answer.

Nocera, 48, is trying to achieve an old, elusive dream:
using the bountiful energy in sunlight to split water into its basic components,
hydrogen and oxygen.

The elements could then be used to supply clean-running
fuel cells or new kinds of machinery. Or the energy created from the reaction
itself, as atomic bonds are severed and re-formed, might be harnessed and
stored.

There is a beautiful model for this: photosynthesis.
Sunlight kickstarts a reaction in which leaves break down water and carbon
dioxide and turn them into oxygen and sugar, which plants use for fuel.

But plants developed this process over billions of years,
and even so, it’s technically not that efficient. Nocera and other scientists
are trying to replicate that – and perhaps improve on it – in decades.

Hydrogen is the most abundant element in the universe, but
it’s generally locked up in compounds with other elements. Currently, it is
chiefly harvested from fossil fuels, whose use is the main cause of carbon
dioxide emissions blamed for global warming.

And so while hydrogen fuel cells – in which hydrogen and
oxygen combine to produce electricity and water – have a green reputation, their
long-term promise could be limited unless the hydrogen they consume comes from
clean sources.

That’s where Nocera’s method comes in. If it works, it
would be free of carbon and the epitome of renewable, since it would be powered
by the sun. Enough energy from sunlight hits the earth every hour to supply the
world for months. The challenge is harnessing it and storing it efficiently,
which existing solar technologies do not do.

“This is nirvana in energy. This will make the problem go
away,” Nocera says one morning in his MIT office, where the Grateful Dead
devotee has a “Mean People Suck” sticker on his window. “If it doesn’t, we will
cease to exist as humanity.”

Lots of people have explored this challenge, but Nocera had
a big breakthrough when he used light to coax multiple hydrogen atoms out of
liquid. The key was figuring out the right chemical catalyst.

Nocera’s 2001 paper on the process in the journal Science,
written with graduate student Alan Heyduk, turned heads. Venture capitalists
rang his phone off the hook offering to fund him in an alternative-energy
company.

The achievement, and its revolutionary prospects, won
Nocera this year’s Italgas Prize, a $100,000 award given annually by an Italian
utility to a top energy researcher.

“Dan is even-money (odds) to solve this problem,” says
Harry Gray, a renowned California Institute of Technology chemist who was
Nocera’s graduate adviser.

But there’s a catch. In fact, there’s a few, and they
illustrate how hard it can be to move alternative energy beyond the
proof-of-concept phase.

Nocera has performed the reaction with acidic solutions,
but not water yet.

The catalyst he used was a compound that included the
expensive metal rhodium. To be a practical energy solution, it will have to be
made from inexpensive elements like iron, nickel or cobalt.

Nocera’s reaction got the photons in light to free up
hydrogen atoms, but that’s only half the equation. The harder part will be to
also capture the oxygen that emerges when water molecules are split. That way,
both elements can be fed into a fuel cell, making the process as efficient as
possible.

Nocera and scientists not affiliated with his work say
those steps are achievable. But first, major advances in basic chemistry will be
necessary for the reactions to be well understood.

As a result, Nocera believes it might be 20 years before
engineers might design systems based on his work. And he frets that too few
scientists are exploring the problem, with many top minds instead focused on
biomedical research.

“This is a massive construction project,” he says. “You can
go back to building New York City in the ’20s and ’30s. You can’t do it with
just a few construction workers. So I need more construction workers, more hard
hats, with me as a hard hat.”

There’s another big hurdle. While Nocera plugs away at
trying to save the world, some people don’t believe it needs saving.

Most scientists concur that continuing to burn fossil fuels
will send the amount of carbon dioxide in the atmosphere – it’s now 35 percent
higher than in preindustrial times – to dangerous levels, causing global
temperatures to rise with potentially devastating effects.

“We are literally poisoning ourselves,” Nocera says.
“People don’t get it because they can’t see it.”

But this is a famously politicized topic in the United
States, where some powerful political leaders question the science behind global
warming. And that, many scientists say, diverts attention and funds from trying
to solve the problem.

And even among people who believe global warming’s risks
are too great to ignore, there is no consensus on what kind of green energy
should come to the rescue.

Nocera cites a calculation by Caltech chemist Nathan Lewis
that power demands in 2050 will be so great that just to keep carbon dioxide
emissions at twice preindustrial levels, a nuclear plant would have to be built
every two days. There’s not enough room on the planet’s surface for other widely
touted solutions such as wind and biomass to have much impact.

Only the sun is the answer, Lewis argues.

Critics of that vision say many energy technologies being
explored – including improved ways of storing electricity and different kinds of
fuel cells – will come online in the next few decades and throw off today’s
extrapolations about the future.

Arno Penzias, who won the Nobel Prize for confirming the
Big Bang and now invests in alternative energy startups for New Enterprise
Associates, contends there are dozens of ideas more promising than ones
involving hydrogen.

When told about Nocera’s project, Penzias gets heated,
saying it is unlikely to be practical.

“It is so far from being revolutionary that it’s not even
worth mentioning,” Penzias says. “It will be a big yawn.”

Nocera seems to thrive on such opposition, because he
expects to prove naysayers wrong.

It’s part of his blunt enthusiasm, which manifests itself
when he discusses the joys of teaching chemistry to freshmen (“They love me”) or
when he meets with his grad students to discuss the status of their
research.

Those sessions often devolve into arguments over the
meaning of some data or the direction that projects ought to take. Provoked by
Nocera’s intensity – he’ll exclaim, “I’m dying here!” in a tone resembling
neurotic comic Larry David – tempers often rise.

One student recently threw an eraser at Nocera, leaving a
pink welt on his back that Nocera later showed off with a laugh.

“There were times I absolutely hated working for him,
because he knew how to press all of my buttons and drive me absolutely insane,”
says Heyduk, now assistant professor of chemistry at the University of
California, Irvine. “He knew I was the kind of person that needed to be
challenged all the time.”

Nocera believes this constant prodding at what’s possible
is the essence of science. As evidence, he reels off several ancillary
developments from his research, including microscopic sensors that detect
biological hazards, which attracted funding from the Defense Advanced Research
Projects Agency.

Pointing to a whiteboard sketch of his vision for using
sunlight to split water, Nocera acknowledges that it ultimately might not be an
energy panacea.

“Is it right? Maybe not. But it will be something. And it
might be something I can’t see right now,” he says. “That’s OK. But you don’t
stop doing something because you can’t see it. It’s antiscientific. It’s
anti-intellectual.”

[Author]

August 13, 2005 at 7:08 AM