LOW-COST ENERGY STORAGE

[spectre]

http://spectrevision.net/2012/08/03/low-cost-energy-storage/
http://www.youtube.com/watch?v=OcGWbt1mcrc

IRON-AIR BATTERIES
http://jes.ecsdl.org/content/159/8/A1209.abstract?sid=4419c3ee-5dd8-409b-b62d-8bfd73e85ad3
http://www.futurity.org/science-technology/breathing-battery-saves-energy-for-rainy-day/
Breaking the barriers for low-cost energy storage / August 1, 2012

A new low-cost, “air-breathing” battery has the capacity to store
between eight and 24 hours’ worth of energy. The rechargeable and eco-
friendly battery uses the chemical energy generated by the oxidation
of iron plates that are exposed to the oxygen in the air—a process
similar to rusting. “Iron is cheap and air is free,” says Sri Narayan,
professor of chemistry at the University of Southern California (USC).
“It’s the future.” Details about the battery were published in the
Journal of the Electrochemical Society. Narayan’s patent is pending,
and both the federal government and California utilities have
expressed interest in the project. Iron-air batteries have been around
for decades—they saw a surge in interest during the 1970s energy
crisis, but suffered from a crippling problem: a competing chemical
reaction of hydrogen generation that takes place inside the battery
(known as hydrolysis) sucked away about 50 percent of the battery’s
energy, making it too inefficient to be useful.

Narayan and his team managed to reduce the energy loss down to 4
percent—making iron-air batteries that are about 10 times more
efficient than their predecessors. The team did it by adding very
small amount of bismuth sulfide into the battery. Bismuth (which
happens to be part of the active ingredient in Pepto-Bismol and helps
give the pink remedy its name) shuts down the wasteful hydrogen
generation. Adding lead or mercury might also have worked to improve
the battery’s efficiency, but wouldn’t have been as safe, Narayan
says. “A very small amount of bismuth sulfide doesn’t compromise on
the promise of an eco-friendly battery that we started with,” he adds.

The California Renewable Energy Resources Act, signed into law by Gov.
Jerry Brown in April 2011, mandates that the state’s utilities must
generate 33 percent of their power from renewable energy sources by
the end of 2020. This aggressive push toward renewable energy sources
presents utilities with a problem: solar power works great on clear
days and wind power is wonderful on windy days, but what can they do
when it’s cloudy and calm out? People still need electricity, and
won’t wait for the clouds to clear to turn the lights on. Currently,
solar and wind power make up a relatively small part of the energy
used in California. In 2009, 11.6 percent of electricity in the state
was generated by wind, solar, geothermal, biomass and small
hydroelectric plants combined. (Large hydroelectric plants accounted
for an additional 9.2 percent.) As such, dips in energy generation
from solar and wind power plants can be covered by the more
predictable coal-burning grid.

As California moves toward more renewable energy, solar- and wind-
power plants will need an effective way of storing large amounts of
energy for use during clouding and calm days. Traditionally, utilities
store power by pumping water uphill into reservoirs, which can then
release the water downhill to spin electricity-generating turbines as
needed. This method is not always practical or even feasible in
drought-ridden California, where water resources are already in high
demand and open reservoirs can suffer significant losses due to
evaporation, Narayan says. Batteries have typically not been a viable
solution for utilities. Regular sealed batteries, like the AAs in your
TV remote, are not rechargeable. Lithium-ion batteries used in cell
phones and laptops, which are rechargeable, are at least 10 times as
expensive as iron-air batteries. Despite his success, Narayan’s work
is still ongoing. His team is working to make the battery store more
energy with less material.

[Collaborators include additional researchers from USC and Andrew
Kindler of NASA’s Jet Propulsion Laboratory at Caltech. Funding for
this research came from the Advanced Research Projects Agency for
Energy, an arm of the US Department of Energy.]

CONTACTS
Sri R. Narayan
http://chem.usc.edu/faculty/Narayan.html
email : srnaraya [at] usc [dot] edu

Danielle Fong
http://lightsailenergy.com/team.html
http://daniellefong.com/about-the-author/
email : Dani.Fong [at] gmail [dot] com

COMPRESSED AIR TANKS
http://www.wired.com/wiredenterprise/2012/07/danielle-fong/#
World's Most Wired Steam Punk
by Caleb Garling / 07.02.12

Danielle Fong was 12 years old when her mother decided she should go
to college. Danielle’s teachers didn’t agree. Though an aptitude test
put her above 99 percent of students who had already graduated from
high school, her teachers said the move to college would ruin her
education. But her mother sent her anyway. “Why would I conceivably
put my child through six more years of that bullshit?” remembers
Danielle’s mother, Trudy Fong, who was 15 when she herself went to
college. “I didn’t bring my kid into the world to have her tortured —
and be treated like dirt for being brilliant.”

Little more than a decade later — after graduating from Canada’s
Dalhousie University and then dropping out of the Ph.D. program at the
Princeton plasma physics lab when she decided academic research was as
broken as grade school — Danielle Fong is the chief scientist and co-
founder of a company called LightSail Energy. Based in Berkeley,
California, this tiny startup is built on an idea that’s as unorthodox
as Fong’s education. LightSail aims to store the world’s excess energy
in giant tanks of compressed air. The goal is to plug these tanks into
wind and solar farms, so that they can squirrel away energy for times
when it’s most needed, much like reservoirs store rain water. The wind
and the sun are prime sources of renewable energy, but they generate
power unpredictably. LightSail’s compressed air tanks, Fong and
company say, will make the power grid that much more efficient — and
ultimately make the world a greener place.

In 2010, Danielle Fong and LightSail took their compressed air storage
idea to the U.S. Department of Energy’sAdvanced Research Projects
Agency, seeking a grant for their work. The agency turned them away,
saying she and her team were unfit to manage a company, that the idea
wouldn’t work anyway, and that her air compressor would likely
explode. But like her mother, Danielle didn’t listen. Backed by $15
million in funding from green-minded venture capital outfit Khosla
Partners and with a team of 32 employees, LightSail is pushing ahead
with its plan to reinvent the power grid. Fong believes the potential
market for compressed air tanks will exceed $1 trillion over the next
20 years. “People get skittish,” says Fong, who is now all of 24. “If
you have your own resources and have a real effort, it doesn’t matter
what the rest of the world thinks, in its knee-jerk, fight-or-flight
response.”

In a way, Fong is going back to the future. Compressed air tanks have
been used to store energy as far back as the late 19th century. They
were installed in cities across the globe, from Paris to Birmingham,
England to Buenos Aires. Germany has been using the technology for the
past 30 years, and a power company in Alabama opened a facility in
1991. The idea is a simple one: If you have a power source — whether
it’s gas or coal or renewable sources such as wind — you can use the
energy to cram air into a tank. When the air compresses, it heats up,
as we all know from high school physics — or just from pumping up a
bicycle tire. Then, when you need the energy at some point down the
road, this stored heat can be turned back into power. It’s a bit like
coiling and releasing a spring. The rub is that you lose power with
each transfer, and you lose heat when the air is in storage. Because
it’s less than efficient, compressed air storage never caught on in a
big way. Current systems often lose more than 50 percent of the power
originally put into them, since they use the released energy to run a
generator — which only loses more power.

Since the 1700s, scientists have struggled to store energy in more
efficient ways, working to refine everything from Galvanic fuel cells
to modern-day batteries. The question is always the same: How do we
build a system that lets us storage energy and then retrieve almost
all of it? But Steve Crane — LightSail’s CEO and a geophysics Ph.D. —
says Danielle Fong has cracked at least part of the code. “It’s a
little arrogant to put it this way,” he says, “but I think that
Danielle has succeeded where Edison and others have failed.” The
trick? Fong added water. LightSail’s prototype sprays a dense mist
into the compressed air tanks, and this absorbs the heat produced
during compression. Water can store heat far more efficiently than
air, and with this mist, Fong says, the prototype more easily stores
and releases power. It heats up the tanks to temperatures that are
only about 10 to 20 degrees warmer than the environment, as opposed to
several thousand degrees. The tanks are still pressurized to about
3,000 pounds per square inch — and Fong hopes to increase that amount
— but since the power is stored at lower-temperatures, it’s easier to
insulate the tanks. Some compressed air storage systems sit deep
underground, taking advantage of the earth’s natural insulation, but
LightSail’s tanks sit above ground, which is less costly. When you
want the heat back, you just reverse the process, spraying the warm
water out of the compression tank as the air expands, and it drives a
piston to reproduce the power. But in both storing the heat and
spitting it out, you need just the right amount of water. LightSail
has tested nearly 40 nozzle heads — not to mention various tank
designs — in an effort to achieve just the right mix. According to
Fong, her system doubles the efficiency of compressed air, from about
35 percent to roughly 70 percent.

You might think of Danielle Fong as a real-life incarnation of
Steampunk, that science-fiction literary genre that re-imagines
Victorian technology in a post-apocalyptic future. The difference is
that her prototype isn’t fiction. Fong’s original plan was to put her
tanks into cars. She holds up Elon Musk, the founder of electric car
pioneer Tesla, as a role model. “He was willing to go all out,” she
says. But rather than equip cars with combustable engines or
rechargeable batteries, LightSail planned to fill them with compressed
air. The hot air would drive the pistons in a new breed of automobile
engine. But after a nudge from their backers, Fong and team decided
that — whatever Musk has accomplished with Tesla — convincing old-
school automakers to put these tanks into their vehicles was an almost
insurmountable task. So she chose another almost insurmountable task:
Reinvent the power grid.

The world is already moving to renewable energy sources such as wind
and solar farms. But these don’t produce a steady stream of power.
Some days you have sun, and some days you don’t. Plus, more power is
typically consumed at night, when solar farms are no longer generating
energy, so you need an efficient way of storing it. Fong envisions a
power grid that behaves more like the internet, where resources are
evenly distributed across the world and they can be readily accessed
whenever they’re needed. Yes, the grid is fundamentally designed to
distribute power to places of need, and we have “peaking plants” that
only operate when additional power is required. But Fong hopes to
provide a level of efficiency the world has never seen, especially in
large countries like India and China, where power grids are less
developed. “It dramatically makes it easier and more economical to do
a network this way,” she says, “rather than in a way where your
expensive assets have to be designed for the peak anticipated loads
over the next 20 years."

Is this doable? According to Samir Succar, a researcher at Princeton
University’s Environmental Institute, compressed air storage could
indeed improve the efficiency of wind and solar farms and other less-
than-predictable energy sources. But he points out that wind and solar
power still accounts for only a small portion of the power grid, and
that compressed air doesn’t make sense for more traditional — and more
predictable — sources such as coal and gas. “We just don’t have
penetration rates that would require energy storage right now,” he
says. What’s more, he says, power companies have little incentive to
build energy storage centers — whether they use compressed air or some
other technology. According to Succar, the power giants prefer to
invest in technologies with a proven history, such as natural gas.
What’s more, because compressed air can mean so many different things,
it can be difficult for these companies to understand which
technologies are the most efficient.

Tom Zarella — CEO of a competing compressed air outfit, SustainX —
agrees that no matter how effective the hardware built by LightSail or
his own company, the task ahead is immense. While some are pushing for
greener forms of energy, the political and economic barriers aren’t
exactly coming down. According to both Zarella and Fong, the collapse
of solar outfit Solyndra — after it had won a $535 million U.S. loan
guarantee — soured investors and turned the political discourse
against alternative energy efforts. “The moment of ‘Me Too!’ investing
in clean energy — where people believe it is easy — is over,” Fong
says. “We realize that.” But she says there are some basic realities
that will float LightSail to the top: air is free, and it’s
everywhere. Any country can use it without depending on another. She
says that some of the company’s initial targets include Third World
countries, isolated towns and islands that operate without power grids
and depend on diesel generators and other local power sources. Much of
the wattage generated by these sources is wasted, she says, and her
compressed air tanks can turn things around. But she’s eying the
United States as well. The Department of Energy’s National Renewable
Energy Laboratory recently released a report saying about 75 percent
of the United States is suited to compress air storage because it
could accommodate buried tanks. But Fong doesn’t need to bury hers.
She can put them anywhere. “We know we can sell as many of these as we
can make,” she says, insisting that by 2015, her company will be
growing threefold every year. “This has never been achieved in any
industrial setting. At all. But there’s no other possible energy
storage solution that can do that. And if we don’t do it, pretty solid
models about the climate — and the way the economy is going to go and
what people will do with coal plants — will fuck the world.” Some may
doubt whether all this will happen. And others may doubt whether
Danielle Fong has the right plan to deal with it. But she’s used to
that.

MEANWHILE : NO STORAGE on the GRID
http://www.youtube.com/watch?v=RX1WqcdgbLk
http://grist.org/news/second-day-of-black-outs-leaves-nearly-10-percent-of-humanity-without-power/
Second day of blackouts leaves nearly 10 percent of humanity without
power
by Philip Bump / 31 Jul 2012

This is not a repeat from yesterday. It is worse. For the second day
in a row, power consumption in India vastly exceeded available supply,
due in part to high temperatures. The result: grid failure that first
struck the northern part of the country — which had the same issue
yesterday — then, the eastern. Reuters suggests that the outage
affected 670 million people — 9.5 percent of all people on Earth. For
nearly four hours, power and transportation systems in the nation’s
capital were at a standstill, forcing hospitals and “VIP zones” to
rely on generator backups. From the Pittsburgh Post-Gazette: "Hundreds
of trains stalled across the country and traffic lights went out,
causing widespread traffic jams in New Delhi. Electric crematoria
stopped operating, some with bodies half burnt, power officials said.
Emergency workers rushed generators to coal mines to rescue miners
trapped underground." At least 46 of the 200 trapped miners have since
been rescued. That coal miners were trapped is not without irony. The
root of India’s electricity problem, exposed by surging demand in high
temperatures, is that a wobbly infrastructure is combined with too
little generation. A business trade group puts the blame for
generation issues specifically on “the nonavailability of coal.” As we
noted last week, the quality of India’s domestic coal is largely too
poor for recent-generation coal plants.

The Times’ Andy Revkin has a good round-up of deeper explanations for
the power failures, further explaining the link between India’s power
problems and its coal problems. He cites theWall Street Journal, which
blames environmental regulations: "More than half of India’s power-
generation capacity of 205 gigawatts is coal-based, and Coal India
Ltd., the world’s biggest coal producer, is unable to produce enough
owing to delays in getting environmental clearances for mining.
Meanwhile, government giveaways in the form of free electricity to
farmers and a reluctance among politicians to raise power tariffs to
sufficiently cover costs have drained cash reserves from the largely
state-run electricity-distribution companies, leaving them with
mounting debt and hampered ability to purchase power." But again, it’s
not clear that mining more coal would solve the country’s problems. If
generation facilities can’t use the coal, there’s not much point in
sending more people down to retrieve it.

EXCEPTION : OFF-GRID SOLAR (MEERWADA, INDIA)
http://www.reuters.com/article/2012/08/01/us-india-solar-idUSBRE8701PT20120801
Off-grid power shines in India solar village
by Jo Winterbottom / Aug 1, 2012

Life in the remote Indian village of Meerwada used to grind to a
standstill as darkness descended. Workers downed tools, kids strained
to see their schoolbooks under the faint glow of aged kerosene lamps
and adults struggled to carry out the most basic of household chores.
The arrival of solar power last year has changed all that. On a humid
evening, fans whirr, children sit cross-legged to study their Hindi
and mother-of-seven Sunderbai is delighted people can actually see
what they are eating and drinking. "When it was dark, we used to drink
water with insects in, but now we can see insects, so we filter it and
then drink," said the 30-year-old, whose flame-orange sari and gold
nose ring are small defiances in a life close to the poverty line.

Meerwada, on a dirt track rutted by rains and outside the reach of the
national grid, struck lucky when U.S. solar firm SunEdison picked it
to test out business models and covered the hefty initial expense of
installing hi-tech solar panels in the heart of the village. But
rapidly falling costs and improved access to financing for would-be
customers could encourage the spread of such systems down the line,
while simpler solar schemes are already making profits in areas where
the grid either does not extend or provides only patchy power. And
Asia's third-largest economy, where just this week hundreds of
millions were left without electricity in one of the world's worst
blackouts, needs all the help it can get in easing the strain on its
overburdened power infrastructure. The country's Ministry of New and
Renewable Energy (MNRE) hopes solar systems that bypass the national
grid will account for just under one percent of total installed
capacity by 2022. Still a mere flicker, but that 4,000-megawatt (MW)
goal would be way up from 80 MW now when so-called off-grid solar
systems are still out of reach for most of the country's rural poor.

Large-scale solar facilities that directly feed the grid, such as
those at an over 600 MW solar park recently launched with great
fanfare in Gujarat, have been gaining traction for some time. But
potential growth in off-grid solar power offers a ray of hope to the
around 40 percent of India's 1.2 billion population that the renewable
power ministry estimates lack access to energy. People like those in
the village just 200 meters away from Meerwada, who rely on a hand
pump for water and cook by torchlight as hungry goats creep up on them
out of the gloom. Covering initial investment on solar is key as, in a
country with around 300 days of sunshine a year, subsequent costs are
largely limited to maintenance and repairs. "The high up-front capital
cost is one of the adoption barriers (for solar projects)," said
Krister Aanesen, associate principal at McKinsey & Company's renewable
energy division. "Although diesel is more expensive on a full-cost
basis, you defer cash outlay for the fuel ... the cash outlays are
different and that's one of the key challenges."

Small-scale direct current (DC) systems from Karnataka in the south to
Assam in the north-east have already cleared that hurdle, supplying
simple lights and mobile phone chargers at 100-200 rupees ($1.80-
$3.60) per month per light -- prices that typically allow installers
to cover their initial costs in time. Private company Mera Gao Power
fits roof-top solar panels and then transmission to other houses who
pay about 40 rupees to connect, with costs thereafter about 25 rupees
per week, said Nikhil Jaisinghani, one of the firm's founders. That
means it should currently take about 12 months to repay panel
installation expenses of about $2,500 for 100 houses, though the cost
is set to fall. Initial expenses are far more onerous on more
comprehensive mini-grids like the one in Meerwada, which includes a
room full of batteries that can store enough electricity to provide
round-the-clock supply to the village and which has recently started
powering water pumps. California-based SunEdison reckons it cost
$100,000-$125,000 to build the 14 kilowatt (KW) plant in Meerwada, an
expense that would have demanded fees way too high for the 400 or so
villagers, whose per capita income is about $250 a year.

The firm expects initial capital costs to come down enough to make
alternating current (AC) systems affordable in villages like Meerwada
in a few years, with improving technology and fierce competition
reducing hardware costs, while enhanced battery storage driven by the
auto industry's push on electric cars is also helping. SunEdison,
which sells solar power plants and services worldwide to commercial,
government and utility customers, has over 50 MW of interconnected
solar electricity in India, with projects ranging from small rooftop
installations to part of the Gujarat solar park. "Three years ago, the
panel price was $2.60 per watt. Today it is 75 cents a watt. I don't
think it will halve in the next few years but I clearly see 50 cents a
watt by 2014/15," said Ahmad Chatila, president and chief executive of
MEMC Electronic, SunEdison's parent company. In the meantime, the
government is offering 30 percent of the project cost and in some
cases low-interest loans for solar power systems under its Jawaharlal
Nehru National Solar Mission policy launched in 2010. But that still
means systems are beyond the reach of many poor, rural customers, so
some solar companies are putting up the 20 percent deposits on loans
required by banks or acting as guarantors for customers who are
outside the conventional banking system.

Back in Meerwada, which lies in central India's Madhya Pradesh, the
villagers have added an unexpected ingredient to the cost equation --
frugality. Lights even now are turned on only when darkness falls and
fans target the youngest children and the elderly, saving on power
use. Only the village leader, Sampat Bai, has been able to afford a
television but it's open to all and her bare-walled main room is
crowded when the latest epic dramas come on screen and the children
have finished their homework. Manorbai, a 30-something mother who is
now making more money by working at night to mend and sew on her
vintage black-and-gold foot-pedal sewing machine, has a simple message
on the future. "Our village has power and other villages should too,"
she said.