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Future Energy eNews
IntegrityResearchInstitute.org June
9, 2006
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1) NanoSolar
Cell Breakthrough - Photons generate 2 or more electrons - efficiency may
double
2) Wind Power
Creates Environmental Rift - People complain about view and effects on the bats
3) Energy and
Fuels - New
Scientist overview with lots of links to future energy information sources
4) Capitol
Hill Renewable Forum - Once a year chance to meet energy pioneers - FREE
admission
5)
Renewables: 25% by 2025 - State governors go ahead of the Feds - www.cleanenergystates.org
6) An
Inconvenient Truth - Global warming science becomes a digestible movie - praise to Al
Gore
1)
Solar power - Seriously Souped Up
Herb Brody,
New Scientist Print Edition, 31 May 2006
http://www.newscientist.com/channel/earth/energy-fuels/mg19025531.600-solar-power--seriously-souped-up.html
IF
YOU want efficient solar power, Victor Klimov has a deal for you. Give him one
photon of sunlight, and he'll give you two electrons' worth of electricity.
Not
impressed? You should be. In all solar cells now in use - in everything from
satellites to pocket calculators - each incoming photon contributes at most one
energised electron to the electric current it generates. Now Klimov, a
physicist at Los Alamos National Laboratory in New Mexico, has
broken through this barrier. He has shown that by shrinking the elements of
a solar cell down to a few nanometres, or millionths of a millimetre, each
captured photon can be made to generate not one, but two or even more
charge carriers.
Producing
this multiplicity of electrons - an achievement that has been replicated by a
group at the National Renewable Energy Laboratory (NREL) in
Golden, Colorado - is a remarkable piece of physics. If the effect can be
harnessed, it could change the whole energy debate by making solar power much
more efficient and economical. While there are many ongoing efforts to improve
solar efficiency - by concentrating sunlight, for example, or by making it
easier for electrons to move around within a cell - the new approach is unique
in that it gets to the very root of the process and also complements other
methods.
For
decades, photovoltaics have been stranded on the effete fringe of energy
technologies - ideal for niche applications such as satellites, but not
economically competitive here on Earth. Made from semiconducting materials, most
often silicon, solar cells convert a dismayingly small fraction of the sun's
energy into electricity. Radically improving efficiency could give solar energy
a boost at a time when it is sorely needed and funding decisions hang in the
balance. "If this could be translated into a robust system that could
generate multiple carriers, it could be revolutionary," says Eric
Rohlfing, acting director of the chemical sciences, geosciences and biosciences
division in the Office of Basic Energy Sciences at the US
Department of Energy.
The latest
results trace back to 1982, when materials scientist Alexander Efros at the Naval
Research Laboratory in Washington DC showed it was theoretically
possible for a photon to generate multiple charge carriers in certain semiconductors.
Over the next two decades, researchers learned to control the properties of
tiny semiconducting structures called nanocrystals, or quantum dots. Then in
2002, physical chemist Arthur Nozik of NREL predicted that the production of
multiple carriers should be enhanced in nanocrystals relative to bulk
semiconductors. It wasn't until 2004 that Klimov's group - interested in
developing lasers as well as photovoltaics - showed that such behaviour could
be reliably detected (Physical
Review Letters, vol 92, p 186601).
The
benefits of multiple carriers arise from the way photovoltaic devices interact
with the solar spectrum. When an electron in a semiconducting material becomes
free to move about and conduct current, it leaves behind a vacant site in the
crystal, called a hole; the electron-hole pair is called an exciton. The amount
of photon energy needed to create an exciton in a particular material is called
the band gap (the term refers to the difference in energy levels between a
fixed electron in the so-called "valence band" and one that is part
of the sea of freely moving electrons in the "conduction band"). Sunlight
consists of a variety of wavelengths, which we see as colours, and the photons
of each colour carry a characteristic amount of energy: lower at the infrared
and red end of the spectrum, and higher towards the blue, violet and
ultraviolet end.
To make an
efficient solar cell, you need to match the photon energy to the cell
material's band gap. Silicon has a band gap that corresponds to wavelengths in
the near-infrared region of the spectrum. Incoming photons with less energy
than that will not have the quantum oomph to create even a single exciton. A
photon with exactly the band-gap energy will create one exciton and have no
energy left over, so the solar cell will make perfect use of the energy from
photons in that part of the spectrum.
Most of the
light streaming down from the sun, however, has a shorter wavelength than
infrared, so its photons have higher energy than the silicon band gap. Each of
these packets of electromagnetic energy, no matter how potent, can still
liberate only one electron. Anything left over will dribble away as heat and
contribute exactly zero to the device's electrical output. Klimov's technique
taps this otherwise wasted energy and turns it into electricity.
The key, he
says, is the small size of the quantum dots used to absorb photons. When
structures shrink to the size of a few thousand atoms, their physics takes a
turn for the weird. The multi-exciton phenomenon, which can barely be made to
occur at all in conventional silicon, becomes possible in specially fabricated
nanocrystals. In his latest series of experiments, Klimov claims to have
produced as many as 7 excitons per photon in crystals of lead selenide 4 to 8
nanometres in diameter (Nano
Letters, vol 6, p 424). "They're very cheap and only take a few
minutes to grow," says Klimov. "It's like making new atoms, to go
beyond what nature provides."
Precision
timing
To detect
these multiple excitons, the nanocrystals' behaviour needs to be measured at
excruciatingly precise time intervals. Klimov and his colleague Richard
Schaller illuminated samples of lead selenide with laser pulses lasting only 5
Χ 10-14 seconds - that's 50 millionths of a
nanosecond. They then shone another laser beam to probe the crystal, monitoring
how much light it absorbed over the next few thousandths of a nanosecond.
Single excitons are stable, so if just one is present, absorption remains
constant during that period. If multiple excitons are created, however, that is
no longer the case: the excitons rapidly disappear, causing the crystal's
absorption properties to change in a characteristic way that can be picked up
by sensitive optical detectors. Of course, the ability of a photon to generate
multiple charge carriers has its limits. The fundamental laws of physics
dictate that the total energy of the excitons cannot exceed the energy of the
photons striking the cell. "We are still constrained by the conservation
of energy," Klimov says.
Or are they?
How the multiple excitons are produced remains a bit of a mystery. According to
Klimov, when an energetic photon strikes the material, the electron jumps to
what he calls a "virtual" state in which it has actually gained more
energy than was carried by the photon; this seeming contradiction is permitted
because the virtual state lasts for such a brief time. The hyper-excited
electron will transfer some of its energy to another, unexcited electron
essentially by bumping into it. The result: two energised electrons from a
single photon.
Nozik
suggests a different model. There is a "coherent superposition" of
energy states, he says - a quantum mechanical effect that defies concrete
analogy. Following the absorption of a high-energy photon, an electron will
inhabit two different energy states: one of them consistent with the formation
of a single exciton, and one consistent with multiple excitons. In effect, says
Garry Rumbles, a member of Nozik's team, "you prepare a mixture of states
- one state looks like three excitons, and another state looks like a single
exciton with very high energy". This superposition holds for a very brief
period, until the electron makes a decision, says Rumbles.
However it
works, a solar cell does no good unless the electric charges created can be
drawn into a circuit. And therein lies the major obstacle to building a
real-world device. "To produce current, you need to separate electrons
from holes, and that's a big problem," Klimov says. The difficulty is that
multiple excitons are extremely short-lived, lasting only tens of picoseconds,
or trillionths of a second, before the holes and electrons recombine; in
ordinary photovoltaic devices, electrons and holes remain apart for much
longer, closer to a microsecond.
This means
that practical applications of Klimov's work are still some way off. "We
can take this as a proof of principle," says chemist Paul Alivisatos of
the University of California, Berkeley, but figuring out how
to separate and harvest the multiple charge carriers produced in a nanocrystal
remains a puzzle. "It's worth spending time on this," he says,
because if it works it is bound to yield an increase in photovoltaic
efficiency.
Nathan
Lewis, a chemist at the California Institute of Technology in
Pasadena who led a recent US Department of Energy workshop on
research needs for solar energy, takes a similar view. The work is an
"important confirmation of theoretical predictions", he says.
"It's like knowing that there's nuclear fusion happening on the sun,"
he explains. "Doing it on Earth is another story."
The first
step is to reliably separate the multiple electrons and holes. That requires
finding materials with electronic energy characteristics that match those of
the quantum dots. One approach uses a conductive polymer to extract the holes.
Klimov's group is collaborating with Anvar Zakhidov, a physicist at the University
of Texas at Dallas, on a prototype that blends the lead selenide
crystals with such a polymer. After a photon creates an electron-hole pair, the
holes migrate into the polymer and travel through it to an electrode; the
energised electrons, meanwhile, hop from nanocrystal to nanocrystal until they
reach the other electrode.
The work
has encountered its share of technical difficulties, however. "We are at
the very beginning of experimental demonstration," Zakhidov says. One
issue is that the nanocrystals must be in "intimate contact" with the
polymer. Moreover, the conduction of electrons through the array of
nanocrystals is very inefficient. "There are lots of dead ends," he
says.
An
alternative method for collecting the solar-induced charges has been proposed
by Peidong Yang, a chemist at Berkeley who is also an expert in nanomaterials.
Instead of requiring electrons to hop from one nanocrystal to another, Yang is
testing nanowires - highly conductive filaments with a diameter of only a few
nanometres. In principle, Yang says, the electrons and holes could zip through
an array of nanowires straight to a pair of collecting electrodes "like
cars on a freeway with no stop lights". Whether nanowires could harvest
multiple excitons in the short time they are available, however, is anyone's
guess.
Another
area for progress is in the material used for making the quantum dots. The lead
selenide used so far is less than ideal. First, it is toxic, making its
fabrication a tricky business. Second, its band gap is large. For a photon to
produce multiple excitons, its energy must equal at least twice the band gap of
the material, and with lead selenide only photons at the high-energy end of the
spectrum are powerful enough to achieve this.
Big
is beautiful
There may
be a way around this. The smallest crystals have the largest band gaps, as the
confinement of electrons to a very tight space ratchets up the energy levels.
The way to generate the largest number of excitons would be to engineer the
crystal so that its band gap is small. One way to do this, says NREL physicist
Randy Ellingson, would simply be to grow the nanocrystals larger. That would
make it possible to use the abundant photons in the middle of the solar
spectrum to generate multiple excitons. The trade-off, Ellingson points out, is
that a lower band gap means a lower voltage across the electrodes, which may
limit the total power output of the cell.
The
researchers are also exploring alternative materials. Both Klimov and Nozik
have observed multiple-exciton generation in other semiconductors, including
lead sulphide, lead telluride and cadmium selenide. What's more, Klimov says
his group has identified two new materials that are less toxic and have band
gaps better matched to the solar spectrum than lead selenide, though he will
not identify the materials as he has yet to publish the work.
If each
photon can generate multiple charge carriers, the overall power efficiency of
solar cells could be dramatically increased. The world record for a
ground-based cell is 24.7 per cent, achieved by a device made in Australia
at the University of New South Wales. Klimov predicts that the multiple-carrier
generation could one day yield a cell with double that efficiency,
approaching 50 per cent. Ellingson is slightly more conservative, but
he still projects efficiencies around 45 per cent. With more work, the chips
cranking out extra electrons in New Mexico and Colorado could one day bring a
bright solar future for us all.
Solar
fuel
Electricity
is not the only useful form of energy that ultra-efficient solar cells might
generate. They could also be used to induce a chemical reaction that creates
fuel. While this approach is not strictly dependent on a cell in which each
photon yields more than one current-carrying electron, the additional charge
carriers would help by accelerating the reaction.
In one
compelling scenario, nanocrystals could be immersed in water, and the current
flowing out of the solar cell would break down the water molecules into
hydrogen and oxygen. As with direct production of electricity, the benefit of a
multiple-exciton solar cell would come through more efficient exploitation of
the solar energy that hits it, says chemist Nathan Lewis of the California
Institute of Technology in Pasadena.
Hydrogen is
the basis for fuel-cell vehicles that would operate emissions-free and require
no gasoline. Oxygen from the air would react with hydrogen in the presence of a
catalyst to produce electricity, with water as a by-product. Calls for a move
to a hydrogen economy, however, tend to gloss over the fact that producing
hydrogen requires energy - and if that energy comes from fossil fuels the
environmental benefit of hydrogen power is questionable. Using solar energy to
generate the hydrogen would overcome this objection.
What's
more, there are other ways of putting a solar fuel generator to work. "I'd
rather do like the plants do," says Lewis. "Use sunlight to convert
water and carbon dioxide into ethanol or methanol." These liquids are more
compatible with existing fuelling stations than hydrogen. Whatever the product,
Lewis says, "making a multiple-exciton-per-photon solar cell for any
purpose would be a major tour de force".
For
more information
Diagram
of Nanosolar Cell: http://www.newscientist.com/data/images/archive/2553/25531601.jpg
Nano
Letters photon article: http://pubs.acs.org/cgi-bin/abstract.cgi/nalefd/2006/6/i03/abs/nl052276g.html
Physical
Review Letters article: http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=PRLTAO000092000018186601000001&idtype=cvips&gifs=yes
2)
Debate Over Wind Power Creates Environmental Rift
By
FELICITY
BARRINGER, New York Times, June 6, 2006, http://select.nytimes.com/mem/tnt.html?emc=tnt&tntget=2006/06/06/us/06wind.html&tntemail1=y
OAKLAND, Md. Dan Boone has no doubt that his crusade
against wind energy is the right way to protect the Allegheny highlands he
loves. Let other environmentalists call him deluded at best, traitorous at
worst. He remains undeterred.
For four years or more, Mr.
Boone has traveled across the mid-Atlantic to make every argument he can muster
against local wind-power projects: they kill birds and bats; they are too
noisy; they are inefficient, making no more than a symbolic contribution to
energy needs.
Wind farms on the empty
prairies of North Dakota? Fine. But not, Mr. Boone insists, in the mountainous
terrain of southwestern Pennsylvania,
western Maryland
or West
Virginia, areas where 15 new projects have been proposed. If all
were built, 750 to 1,000 giant turbines would line the hilltops, most
producing, on average, enough electricity to power 600 homes.
Wind projects are in the
midst of a huge growth spurt in many parts of the country, driven by government
incentives to promote alternatives to fossil fuels. But Mr. Boone, who wields a
botanist's trowel and a debater's knife with equal ease, wants to slow them
down with community activism, regulatory action and legal challenges.
His crusade harks back to
the campaigns against nuclear power plants, toxic-waste dumps and dams on
scenic rivers that were building blocks of the modern environmental movement.
But the times, and the climate, are changing. With fears of global
warming growing more acute, Mr. Boone and many other local activists
are finding themselves increasingly out of step with the priorities of the
broader movement.
National groups like Greenpeace
and the Sierra Club used to uniting against specific projects are now united
for renewable energy in general. And they are particularly high on wind power
with the caveat that a few, but only a few, special places should be
turbine-free.
"The broader
environmental movement knows we have this urgent need for renewable energy to
avert global warming," said John Passacantando, executive director of Greenpeace
U.S.A. "But we're still dealing with groups that can't get their
heads around global warming yet."
Indeed, the best winds,
especially in the East, tend to blow in places that are also ideal for hiking,
sailing, second homes and spirit-soothing views. These include the Green
Mountains, the Adirondacks, the Chesapeake Bay, Cape Cod and the ridges of northern
Appalachia. Local opposition to unwanted development remains a potent force.
So when it comes to wind,
the environmental movement is riven with dissonance and accusations of elitism.
Robert
F. Kennedy Jr.'s very public opposition to the 130-turbine
Cape Wind energy facility proposed off Nantucket Sound has driven a wedge
between activists. Dan Boone's circuit riding against wind projects, while not
attracting the same celebrity notice, has exasperated many Sierra Club
compatriots even more.
Like Mr. Kennedy, Mr. Boone
says the areas he wants to protect are uniquely vulnerable. His family owns
property near the proposed projects, just as Mr. Kennedy's does near the Cape
Wind site.
But Mr. Boone says that
wind supporters are the ones pursuing their own agenda at the expense of the
public interest.
"I'm not sure that
wind turbines in this region will significantly reduce the outcome of global
climate change or actually have any role," Mr. Boone said. "The very
limited benefit doesn't justify the risk of wiping out a lot of interior forest
habitat."
National environmental
leaders reject this argument.
"There's no free
lunch," said Paul Hansen, executive director of the Izaak Walton
League of America, a venerable sportsmen's group. " 'Not in my
backyard' is not environmentalism."
The Alleghenies are a big
backyard, with views that are both spectacular and problematic. Flowering
shrubs like shadbush and preening flowers like trillium are framed by oaks,
maples and longleaf pines. But intermittent industrial tree farming has
repeatedly denuded some mountainsides. On both sides of the border near here in
far western Maryland, second-home development is booming. The air has often
been fouled by the Mount Storm coal-fired power plant.
If Ned Power,
a wind-energy development company, puts up 100 or so turbines along 14 miles of
ridgeline near Mount Storm, wind-energy supporters say, how much does that
further spoil the landscape?
Kevin Rackstraw, a regional
manager of Clipper Windpower whose proposed 40-turbine project
in western Maryland has drawn Mr. Boone's fire, said opponents lacked perspective.
"Dan looks at all the
impacts of a given wind project," Mr. Rackstraw said, "but doesn't
say: 'If we didn't have wind, what would we have?' Coal. Think of the impact of
acid rain and mountaintop removal."
The Ned Power project is
just one target of Mr. Boone, 49, a former state wildlife biologist who now
works as a consultant. In interviews, he said he first focused on the issue
when working as a botanist on a study related to an early wind power project.
The environmental-impact statements, he said, were grossly inadequate.
Now he drives from Highland
County in western Virginia (where 38 turbines are proposed on Tamarack Ridge)
to Bedford, Pa. (where early discussions of an unnamed project are under way)
to talk to local groups or crystallize their objections for them. In Annapolis,
Md., and Charleston, W.Va., he uses state utility regulators' licensing
hearings to throw up roadblocks before wind projects. He is eager to argue with
industry officials in any venue, questioning their facts, assumptions and
motives.
"The rush is on now
because a lot of the places they've targeted have no zoning, and it's easy to
get in that kind of large-scale development," he said. "This part of
the country has really good energy prices. Developers are keying in on that."
Mr. Boone's quiver of
anti-wind arguments includes economic analyses, but his first line of attack is
biological: he contends that they are a threat to bats and potentially to
migratory birds and that they break up forest habitat.
Scores of raptors and other
birds were killed by the first generation of wind turbines set up at Altamont
Pass in Northern California. Since the Altamont Pass turbines were erected in
the early 1980's, turbine design has been altered, and most subsequent studies
have shown that birds tend to fly above the height of most turbines though some
experts say more studies are needed.
But the turbines south of
here in Thomas, W.Va., have been lethal to bats. More than 2,000 were killed in
2003 at the Mountaineer project, whose 44 turbines are owned by FPL Energy, a
big power company that is the wind industry's dominant player.
Industry officials agree
that the bat mortality measured at the Mountaineer site is unacceptable, and
they are studying the benefits of deterrent devices and the best ways to modify
turbine operations in bat-rich areas.
To Mr. Boone, wind energy
will never make a big enough difference to justify its impact in the region.
"You have to remember that these tax advantages are so huge," he
said, "that these developers are keen to latch onto all the mythology
whether it's global warming or something else."
Asked if he thought global
warming was a myth, he said: "No, I'm not calling it mythology." But
industry officials, he contended, will "take things out of context."
Mike Tidwell, the director
of Chesapeake Climate Action Network and one of Mr. Boone's
adversaries, bristles at the attack. "Wind industry guys are the
straightest-shooting people," Mr. Tidwell said. "Most got into it
because they had an environmental ethic."
But Mr. Boone has plenty of
allies, too. "He's the greatest naturalist I've even known," said
Betsy Johnson, chairwoman of the Maryland chapter of the Sierra Club. "Dan
has been very helpful in educating us with what problems there can be with an
energy source like wind."
The industry Mr. Boone
regards so suspiciously is on a roll. The total share of energy that wind farms
generated nationwide in 2004 was tiny about one-third of 1 percent, according
to the Energy Department. But by 2020, according to industry estimates, wind's
share of the county's energy portfolio could grow ten- or twentyfold.
For the environmental
movement, wind supporters say, the transition from the protection of place to
the protection of planet is bound to be wrenching.
"Wilderness
conversations are spiritual," said David Hamilton, the Sierra Club's
national director of global warming and energy programs. "We've always
been a place-based organization, protecting places," but "protecting
our climate" is "just looking at it from a different angle and a
different elevation."
3) Instant Expert: Energy and Fuels
John
Pickrell, New Scientist, 26 May 2006, http://www.newscientist.com/popuparticle.ns?id=in158
Access to
cheap energy is a linchpin of modern industry and civilisation. Energy, mostly
from fossil fuels, allows us
to heat homes, and power factories and transportation systems. Worldwide every
day, we devour the energy
equivalent of about 200 million barrels of oil, but much of this energy comes
from coal, gas and nuclear fuel too.
Starting with coal, and then oil and
gas in the 1800s, we have plundered our fossil fuel riches to drive development. But
now, an energy crisis looms. New oil sources are dwindling,
and smothering greenhouse gases
threaten the Earth - yet energy demands will rise by 50% to 60% by 2030. We
need to rapidly develop sustainable solutions - from hydrogen cells to wind turbines - to fuel
our future.
Most of the energy on Earth
comes from the Sun. In fact enough
energy from the Sun hits the planet's surface each minute to cover our needs
for an entire year, we just need to find an efficient way to
harness it. So far the energy in oil has been cheaper and easier to get at.
But as supplies dwindle, this will change, and
we will need to cure our addiction to oil.
Thirst for oil
Burning wood
satisfied most energy needs until the steam-driven industrial
revolution, when energy-dense coal became the fuel of choice. Coal is
still used, mostly in power stations, to cover one-quarter of our energy needs,
but its use has been declining since we started pumping up oil. Coal is the
least efficient, unhealthiest and most
environmentally damaging fossil fuel, but could make a comeback, as
supplies are still plentiful: its reserves are five times larger than oil's.
Today petroleum
(derived from oil) provides around 40% of the world's energy needs, mostly
fuelling automobiles. The US guzzles up a quarter of
all oil, and generates a similar proportion of greenhouse gas
emissions. The first wells were drilled 2400 years ago,
but the modern oil industry was born in the 1850s.
The majority of oil comes
from the Middle East, which has
half of known reserves. But other significant sources include Russia, North America, Norway, Venezuela and
the North Sea. Alaska's Arctic National Wildlife Refuge
could be a major new US source, to reduce reliance on
foreign imports, but drilling there is currently prohibited.
Most experts predict we
will exhaust easily accessible reserves within 50 years, though opinions and estimates vary. We
could fast reach an energy crisis in the next few decades; when demand outstrips supply.
As conventional reserves become more difficult to access, others such as oil shales and tar sands may be used instead. Petrol
could also be extracted from coal.
Since we started using
fossil fuels, we have released 400 billion tonnes of carbon, and burning the
entire reserves could eventually raise world temperatures by 13°C. Among other horrors,
this would result in the destruction of all rainforests and the
melting of all Arctic ice. London
would be as hot as Cairo, but would also be engulfed by seawater.
(See our Special Report on Climate Change for
more.)
Gas, naturally
Natural gas reserves could plug some of the gap
from oil, but reserves of that - some of which are in Russia, the Middle East
and the Wadden Sea - will not
last into the 22nd century either. We currently use it
for around one-third of world electricity generation.
Natural gas, which is
mostly methane, is the cleanest fossil fuel by
weight, emitting just 40% the greenhouse gases of coal and 25% of oil. As a
less-polluting alternative to petrol, its use is increasing in automobiles -
either as compressed natural gas
or for powering hydrogen fuel cells.
When reserves do run low, we may be able to access vast frozen methane hydrate
reserves beneath the seabed.
In the next few decades,
one way for the UK and others to
meet greenhouse gas reduction commitments, could be increased nuclear power
generation. Currently, about 440 reactors in 32 countries generate 16% of world
electricity. (See our Special Report on The Nuclear Age for
more.)
Despite a slow decline of
support for nuclear power in the
west following the Chernobyl disaster in
1986, many countries, such as the US, Japan and India are now embracing
the technology again. But using nuclear power to mitigate environmental damage
is a double-edged sword,
because disposing of nuclear waste is itself
an intractable problem. Expense, safety in usual
operation and terrorism are major concerns too, not
to mention the fact that building new facilities can take decades.
Sustainable alternatives
Less-polluting renewable
energy sources offer a more practical long-term energy solution. They may benefit the world's poor
too. "Renewable" refers to the fact these resources are not used
faster than they can be replaced.
The Chinese and Romans used
watermills over 2000 years ago.
But the first hydroelectric dam was
built in England in 1870. Hydroelectric power is now the most common
form of renewable energy, supplying around 20% of world electricity.
China's Three Gorges Dam, which
has just been completed, is the largest ever. At five
times the size of the US's Hoover Dam, its 26 turbines will generate the
equivalent energy of 18 coal-fired power stations. It will satisfy 3% of
China's entire electricity demand. Surprisingly, some argue that hydroelectric
dams significantly contribute greenhouse
gases.
In 2003, the first commercial power station
to harness tidal currents in the
open sea opened in Norway. It is designed like windmill, but others take the
form of turbines, oscillating hydroplanes,
flexible eel-like generators, or
are made of floating pontoons that rise up and down with the waves and tide.
As prices fall, wind
power has become the fastest growing type of
electricity generation - quadrupling worldwide between 1999 and 2005. Modern
wind farms consist of turbines that generate
electricity. Though it will be more expensive, there is more than enough wind
to provide the world's entire energy needs.
Wind farms come in onshore
and offshore forms. They
can often end up at spots of natural beauty, and are
often unpopular with
residents. And turbines are not totally benign - they can interfere with radar
and leave a significant ecological footprint; altering climate,
sending wildlife diving for cover and
killing sea birds. Migrating
birds may have more luck avoiding
them.
Scotland is building Europe's largest wind farm,
which will power 200,000 homes. The UK's goal is to generate one-fifth of power
from renewable sources, mainly wind, by 2020. But this may cause problems, because wind
is unreliable.
Future buildings with integrated turbines
could generate 20% of their own power. Other visions see wind-power revived for
shipping, floating wind farms, or
28-kilometre-wide flying behemoths
powered by high speed winds in the upper atmosphere. There are also plans to
construct a 1-kilometre-tall tower
that would harness wind energy from heated air in the Australian outback.
Catching some rays
Using solar power to
generate electricity has been considered since Victorian times and
clever building designs that use it to regulate temperature
have been around for millennia. Today solar power is used in several ways. In thermal solar power,
sunlight directly heats water in rooftop panels for household supplies, while
sunlight can also be converted to electricity
using photovoltaic cells,
which use semiconductors to turn photons into electricity.
Both types of power are
intermittent sources, as they can only work in good light. Photovoltaic cells have
been too expensive for widespread use, but are already popular for supplying
electricity to remote locations and filling gaps in
ramshackle electricity grids. Solar panels often power spacecraft too,
and solar cars and aeroplanes.
New cheaper versionsof
photovoltaic cells could mean more energy is generated from solar
than nuclear power by 2020.
In the future we may
generate solar power using flexible coverings that
"clothe" both buildings and people. There is even a
scheme for an orbiting solar power station.
Running on empty
When oil runs out what will
we fuel our cars with? This question, plus the fact the exhaust fumes are one
of the greatest contributors
to greenhouse gas emissions, means the race is on to find a
new solution to getting around.
Biofuels have been around since the internal
combustion engine. Ethanol is added to
petrol in the US, and millions of cars in Brazil are run on it
too. Vegetable oils are
already used in Europe to produce biodiesel. Soya oil could be used
for aviation too. Biofuels such as
fast-growing elephant grass or saplings could be used
to provide heat and electricity. Even sewage is being
considered as a biofuel.
Hydrogen fuel cells have enormous potential if
technical problems can be solved. Essentially a kind of battery that can be
continuously refilled, fuel cells chemically
react hydrogen with oxygen - producing just electricity and water.
This is a far more
efficient process than burning fuel, as much less energy is wasted as heat. See
how it works here. But it's not just
useful in cars: hydrogen could also be used in power stations and electronic and portable gadgets too.
Miniature fuel cells may one day oust batteries.
The problem is that catalysts and membranes have been expensive until recently.
Other problems include making tanks of pressurised flammable hydrogen safe
enough for cars and creating an entire fuelling station infrastructure.
Combining traditional engines with fuel cells
could be step in the right direction. A new $10 million prize has
been offered to help solve these problems.
Fuel cells can also use
natural gas, methanol or coal - but these
produce carbon dioxide. Hydrogen is not yet a completely clean either, as
electricity - currently derived from fossil fuels - is needed
to"crack" water to produce the hydrogen. Some cities, such as
Reykjavik, already use hydrogen to power buses. But
Iceland gets some electricity and over 80% of its heating and hot water
from geothermal energy sources, and can produce the hydrogen
emission-free. Other countries need to find ways to produce the hydrogen sustainably.
Driving efficiency
Some argue that the
"hydrogen economy" is a distraction from
meeting future energy needs and slowing climate change, and
that we need to focus on more immediate solutions.
Making social change might be
more difficult than solving technical problems.
Solutions that could be put
in place right now include filtering carbon
dioxide out of emissions and burying it in oil seams
or under the sea. The US
is among 6 nations that have turned their back on
the Kyoto protocol to curb climate change and are focusing instead on "clean energy" from
fossil fuels.
Increasing efficiency in energy production could also
yield massive savings, as it did during the oil crises of the 1970s. Methods
vary from reducing the friction
of trains to lowering speed limits
for cars.
Producing combined heat and power
with small generators at home,
makes use of a lot of the energy wasted in power
stations, and might one day feed energy back to the grid. Wind and solar power
could also be rigged up on a rooftop near you in the future - even the Queen of England is now
generating her own power from the River Thames.
4) The
9th Annual Renewable Energy & Energy Efficiency Expo and Forum
Tuesday, June 20, 2006
9:00 a.m. 5:00 p.m.
345 Cannon House Office Building (Cannon Caucus Room)
Presented by The Sustainable Energy Coalition (SEC) and the
House and Senate Renewable Energy & Energy Efficiency Caucuses
*A full list of exhibitors is featured at the bottom of this
notice*
9:00 10:00
a.m. Official Expo Opening with Members & Invited Guests
Representative Mark Udall (D-CO),
Co-chair, House Renewable Energy and Energy Efficiency Caucus
Representative Zach Wamp (R-TN),
Co-chair, House Renewable Energy and Energy Efficiency Caucus
Alexander Karsner, Assistant
Secretary for Energy Efficiency and Renewable Energy, Department of
Energy INVITED
Philip W. Grone, Deputy Under
Secretary of Defense, Department of Defense
Press Conference
11:00 a.m. 12:30
p.m. Panel 1: "Achieving True Energy Supply Security With Sustainable
Resources"
Chair: Representative
Mark Udall (D-CO), Co-chair, House Renewable Energy and Energy Efficiency
Caucus
Panelists:
Scott Trainum, Past Chairman, Adkins
Energy
David Youlen, Vice President,
Brookfield Power
Representative from National Oceanic
and Atmospheric Administration (NOAA) - TBD
Rich Halvey, Program Manager,
Western Governors' Association
1:15 2:30 p.m. Panel 2: "Improving the Economy
and Solving the Energy Crisis through Sustainable Resources"
Chair: Representative
Sherwood Boehlert (R-NY), Chair, House Science Committee INVITED
Panelists:
Jon Weisgall, Vice President,
MidAmerican Energy Holdings Company
Chris OBrien, Vice President
for Strategy & Government Relations, Sharp Solar
Systems
Kevin Rackstraw, Development
Leader, Clipper WindPower Inc.
3:30 4:15 p.m. Panel 3: "Increasing Energy
While Decreasing Greenhouse Gas Emissions -- The Unique Role of Efficient,
Sustainable Technologies"
Chair: Phil Sharp,
President, Resources for the Future
Panelists:
Tom Casten, President & CEO,
Primary Energy
Dr. Michael MacCracken
5:00 6:30 p.m. Reception Sponsored by General Electric (GE)
Closing Remarks and presentation of
a Lifetime Achievement Award to Representative Sherwood Boehlert from the
Sustainable Energy Coalition (SEC).
A DVD showcase of some of the most promising renewable
energy and energy efficiency technologies available today will play in a
room adjacent to the Expo. Please drop in at any time during the event to
view 5- to 15-minute segments about the following technologies: geothermal,
biomass, hydropower, solar, wind, ethanol, biodiesel, fuel
cells, hydrogen, home energy efficiency, and high-performance schools.
Light refreshments will be served
and no RSVP is required. Please feel free to forward this notice.
For more information, contact Jennifer Hinrichs at (301) 219-6249 or visit
the websites of the following co-sponsoring organizations:
American Wind Energy Association (www.awea.org)
Biomass Coordinating Council/American Council on Renewable Energy (www.acore.org)
Combined Heat and Power
Association (www.chpa.co.uk)
Environmental and Energy Study Institute (www.eesi.org)
Geothermal Energy Association (www.geo-energy.org)
National Hydropower Association (www.hydro.org)
Renewable Fuels Association (www.ethanolrfa.org)
Solar Energy Industries Association (www.seia.org)
The Stella Group, Ltd. (www.thestellagroupltd.com)
2006 Renewable Energy & Energy Efficiency Expo
Exhibitors
Biofuels
Renewable Fuels
Association
Biomass Coordinating Council/American Council on Renewable Energy
Austin Energy/Plug-In Partners
Iogen Corporation
CHOREN Corporation
Combined Heat and Power (CHP)
Enercon Engineering
Inc.
Brennan Downes, Primary Energy
Caterpillar
Cummins Power Generation
Distributed Generation/Efficiency
Fuel Cell
Association
GridPoint
Ocean Power Technology
Polyisocyanurate Insulation Manufacturing Association (PIMA)
Solargenix Energy
Geothermal
Ormat Technologies
Geothermal Education Office (GEO)
Hydropower
Voith Siemens Hydro Power Generation
Grant County PUD, District No. 2
WaveGen
Verdant Power
Solar
Sharp
Unisolar
Schott
Solar Integrated Technologies
Wind
Southwest Windpower
Clipper Windpower, Inc.
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5) Renewables: 25%
of energy use in '25?
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Jun 9, 2006,
Brad
Knickerbocker
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Christian Science Monitor http://www.csmonitor.com/2006/0609/p02s02-uspo.html
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A broad coalition of politicos,
activists, and businesses united this week to try to put greener
energy on a fast track.
With gas prices at $3 a gallon as far as the
eye can see, plus increasing prospects of global warming and war in an
oil-rich part of the world, the heat is on to wean the nation from fossil
fuels.
In Washington this week, a bipartisan group of
lawmakers, industry leaders (including the three Detroit automakers), farm
groups, governors, county officials, and environmentalists launched an effort
to have the nation get 25 percent of its total energy from renewable sources
by 2025.
This ambitious proposal - dubbed
"25x'25" - goes well beyond what Congress and the White House have
enacted so far, and it's likely to encounter environmental and economic speed
bumps along the way.
The goal of securing one-fourth of the nation's
total energy from renewable sources such as wind, solar, biomass, and biogas
by 2025 was introduced this week as a concurrent resolution in both houses of
Congress. So far, it has at least 30 cosponsors with the number growing daily.
"I think that this goal is definitely
achievable," says Rep. Collin Peterson (D) of Minn., the ranking member
of the House Committee on Agriculture. "I think we're
going to beat this 25 percent in 25 years."
Seen one way, this new energy effort is a coalition
of well-known special interests like ethanol producers, tree farmers, and
solar equipment manufacturers. But boosters believe a critical mass of public
support has developed that puts a strong political wind at their backs.
One example: The kick off session for the
annual meeting of the Western Governors Association this
weekend in Sedona, Ariz., focuses on clean energy. The WGA, whose 18 state
executives (11 of whom are Republicans) oversee the fastest growing states in
terms of population and energy consumption, will propose the development of
30,000 megawatts of "clean and diverse energy" across the American
West by 2015 while increasing energy efficiency 20 percent by 2020.
Meanwhile, 14 states participating in the Clean
Energy States Alliance have set up special funds to promote
commercialization of renewable energy technology. www.cleanenergystates.org
Prominent backers of "25x'25" span
the political spectrum, from former US House Speaker Newt Gingrich to John
Podesta, former chief of staff to President Bill Clinton. So far, seven
governors (four Republicans and three Democrats) have signed on, as have
state legislatures in Colorado, Nebraska, Kansas, and Vermont. A list of some
140 supporting organizations ranges from the National Wildlife Federation to
the Texas Farm Bureau to the American Bankers Association.
The public seems to like the idea as well. A
recent poll by Public Opinion Strategies of Alexandria, Va., shows that 98
percent see shifting to domestically-produced renewable energy sources as
important for the country with 74 percent agreeing that it is "very
important."
Meanwhile, there are new indications that such
an effort could work. The Worldwatch Institute this week reported that
biofuels can significantly reduce global dependence on oil.
Oil still accounts for more than 96 percent of
transportation fuel use, but biofuel production has doubled since 2001 and it
is poised for even stronger growth as the industry responds to higher fuel
prices and supportive government policies, Worldwatch reported.
The result, the research organization predicts,
is that advanced biofuels could provide 37 percent of US transport fuel
within the next 25 years, and up to 75 percent if automobile fuel economy
doubles.
Given the rather tortuous history of energy
legislation, translating ambitious goals for renewables into specific
legislation with adequate funding will take considerable political effort.
The six senators and representatives (three Republicans and three Democrats)
who introduced "25x'25" as a national goal Wednesday acknowledged
as much.
Meanwhile, the various elements of clean energy
each have their own challenges.
Wind turbines, for example, have sprouted at an
accelerated rate around the country in recent years. But opponents say the
giant bladed towers (some reaching as high as 40 stories) create visual
pollution and can kill bats and migrating birds by the thousands.
As part of a military spending bill, Congress
ordered the Pentagon to study whether wind towers mask radar signals,
allowing small and possibly threatening aircraft to penetrate restricted
areas.
As a result, the FAA has blocked new wind farms
that might interfere with military radar, including more than a dozen in the
Midwest.
Last week, the six US Senators from Wisconsin,
Illinois, and North Dakota wrote to Defense Department and FAA officials
asking that the agencies "not unnecessarily obstruct the implementation
of this major source of domestic, clean energy."
"Since much of the nation is in radar line
of site, this interim policy has a sweeping effect," the senators'
letter stated. "Prohibiting, even temporarily, the development of wind
energy facilities within those areas would be a considerable setback for
efforts to increase our country's energy independence."
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6) Warning of
Calamities and Hoping for a Change in 'An Inconvenient Truth'
By A. O. SCOTT May 24, 2006 http://movies2.nytimes.com/2006/05/24/movies/24trut.html?pagewanted=print
MOVIE REVIEW
CANNES, France, May 23 "An Inconvenient Truth," Davis Guggenheim's
new documentary about the dangers of climate change, is a film that should
never have been made. It is, after all, the job of political leaders and
policymakers to protect against possible future calamities, to respond to the
findings of science and to persuade the public that action must be taken to
protect the common interest.
But when this does not happen and it is hardly a partisan statement to
observe that, in the case of global warming, it
hasn't others must take up the responsibility: filmmakers, activists,
scientists, even retired politicians. That "An Inconvenient Truth"
should not have to exist is a reason to be grateful that it does.
Appearances to the contrary, Mr. Guggenheim's movie is not really about Al Gore. It consists mainly of a
multimedia presentation on climate change that Mr. Gore has given many times
over the last few years, interspersed with interviews and Mr. Gore's voice-over
reflections on his life in and out of politics. His presence is, in some ways,
a distraction, since it guarantees that "An Inconvenient Truth" will
become fodder for the cynical, ideologically facile sniping that often passes
for political discourse these days. But really, the idea that worrying about
the effect of carbon-dioxide emissions on the world's climate makes you some
kind of liberal kook is as tired as the image of Mr. Gore as a stiff, humorless
speaker, someone to make fun of rather than take seriously.
In any case, Mr. Gore has long since proven to be a deft self-satirist. (He
recently told a moderator at a Cannes Film Festival news conference to address
him as "your Adequacy.") He makes a few jokes to leaven the grim gist
of "An Inconvenient Truth," and some of them are funny, in the style
of a college lecturer's attempts to keep the attention of his captive audience.
Indeed, his onstage manner pacing back and forth, fiddling with gadgets,
gesturing for emphasis is more a professor's than a politician's. If he were
not the man who, in his own formulation "used to be the next president of
the United States of America," he might have settled down to tenure and a
Volvo (or maybe a Prius) in some leafy academic grove.
But as I said, the movie is not about him. He is, rather, the surprisingly
engaging vehicle for some very disturbing information. His
explanations of complex environmental phenomena the jet stream has always
been a particularly tough one for me to grasp are clear, and while some of
the visual aids are a little corny, most of the images are stark,
illuminating and powerful.
I can't think of another movie in which the display of a graph elicited
gasps of horror, but when the red lines showing the increasing rates of
carbon-dioxide emissions and the corresponding rise in temperatures come on
screen, the effect is jolting and chilling. Photographs of receding ice fields
and glaciers consequences of climate change that have already taken place
are as disturbing as speculative maps of submerged coastlines. The news of
increased hurricane activity and warming oceans is all the more alarming for
being delivered in Mr. Gore's matter-of-fact, scholarly tone.
He speaks of the need to reduce carbon-dioxide emissions as a "moral
imperative," and most people who see this movie will do so out of a sense
of duty, which seems to me entirely appropriate. Luckily, it happens to be a
well-made documentary, edited crisply enough to keep it from feeling like 90
minutes of C-Span and shaped to give Mr. Gore's argument a real sense of drama.
As unsettling as it can be, it is also intellectually exhilarating, and, like
any good piece of pedagogy, whets the appetite for further study. This is not
everything you need to know about global warming: that's the point. But it is a
good place to start, and to continue, a process of education that could
hardly be more urgent. "An Inconvenient Truth" is a
necessary film.
"An Inconvenient Truth" is rated PG (Parental guidance
suggested). Some of the subjects discussed might be upsetting.
An Inconvenient Truth
Directed by Davis Guggenheim; produced by Laurie David, Lawrence Bender and
Scott Z. Burns; released by Paramount Classics and Participant Productions.
Running time: 96 minutes.
For more information
Official
movie website: www.climatecrisis.net
View movie
trailer: http://movies2.nytimes.com/gst/movies/trailer.html?v_id=342290
NEWS FLASH:
*
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attend our Conference on Future Energy, September 22-24, 2006,
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