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In case you didn't get the news on my public appearance last
month in Colorado, my 45-minute talk on the "Progress in
Breakthrough Future Energy Technologies" is still available
online. It's under "Friday Morning Talks Tent 1, Thomas
Valone" on http://coldfusionnow.org/global-breakthrough-energy-movement-rising-up/,
thanks to the Cold Fusion Now organization who have helped archive the
videos from theBreakthrough Energy Movement (BEM)
conference. The presentation has the best and most condensed
information about our IRI latest energy advocacies and endeavors.
Speaking of our years of efforts in volunteering to keep IRI afloat
serving the public in energy programs not presently addressed by ANY
other organization, this month is our annual IRI fund-raising drive.
Please consider helping us in some way so we may continue our
future-oriented service mission as a charitable 501(c)3 nonprofit. An IRI membership is well worth it. If
you join by December 7th, we can include you in the
end-of-the-year IRI Members' quarterly
mailing which always includes a surprise energy-related
present for every IRI Member such as this year's true, free energy flashlight
that never needs batteries. You will also have an additional quarter
bonus if you join by midnight December
7th since our Membership Renewal is every Spring but your
membership will extend through all of 2014!
Our lead story this month is an exciting energy harvesting
discovery since it points the way for much of the future energy
trends today. Similar to the Moddel and Degenais rectennas you
can see in my BEM talk, the #1 story is closer to the Delft and
Eindhoven Universities' energy harvester from the August FE eNews with almost the
same resonant frequency around 900 MHz. However, this metamaterial
product advertises a whopping 37% efficiency, competing with solar PV,
and can be ganged together in series for energy harvesting upgrade.
Every so often we get a question about dark energy and
its relation to the quantum vacuum. More and more physicists are buying
into the fundamental nature of dark energy based on quantum mechanics
zero point energy, rather than the speculative "dark"
implications of the unknown that cosmologists would have us believe. At
the same time that the most sensitive experimental measurement of dark matter at Sanford
Underground Lab has failed to find any WIMPs in our solar
system, the simplest dark energy hypothesis, that it has remained
constant over time, is also coming into question in Story #2. Our IRI
position is that the dark energy phenomena of the cosmological constant
that is pushing the galaxies apart in an accelerated fashion is a
quantum vacuum variation of the Repulsive Casimir force, which is
known to depend heavily on geometry from the work of Dr. Jordan Maclay
who found the relation of negative and positive Casimir forces with a
NASA grant, as reported in Zero Point Energy, Fuel of the Future.
Our Story #3 reflects an emerging electrotherapy in
bioenergetics that IRI is advocating. Fighting paralysis with electricity is
an ongoing field of research involving neuronal stimulation as reported
in New Scientist as far back as 2008 "Broken nerves are fixed in a
flash". The more recent book on the subject, The Spark of Life, Electricity in the
Human Body by Frances Ashcroft released in 2012 also touches
on paralysis and electricity.
I just subscribed to another news service called GreenTechMedia.com that
has a wealth of information about solar and other green technologies.
How valuable can this be? Our Story #4 shows the result of a study
performed on West-facing vs. South-facing rooftop solar PV systems. The
surprise is that West-facing panels can produce about 50% more
electricity during peak demand, which can be monetarily valuable in
some areas.
Now the Story #5 however probably could have been the lead story
for many reasons. The most important is that it displays a new trend of
eight (8) states in this country conspiring to boost the use of electric cars and
other zero emission vehicles (ZEV), including
lower electricity rates for home charging stations and more charging
stations statewide. With electricity costs already about 2/3 less per
mile than gasoline, there is a good incentive to consider an electric
car.
Sincerely,
Thomas
Valone, PhD, Editor
1) Wireless Device Converts
"Lost " Energy into Electric Power
Using
inexpensive materials configured and tuned to capture microwave signals,
researchers at Duke University's Pratt School of Engineering have
designed a power-harvesting device with efficiency similar to that of
modern solar panels.
The
device wirelessly converts the microwave signal to direct current voltage
capable of recharging a cell phone battery or other small electronic
device, according to a report appearing in the journal Applied Physics Letters in
December 2013. (It is now available online.)
It
operates on a similar principle to solar panels, which convert light
energy into electrical current. But this versatile energy harvester could
be tuned to harvest the signal from other energy sources, including
satellite signals, sound signals or Wi-Fi signals, the researchers
say.
The
key to the power harvester lies in its application of metamaterials,
engineered structures that can capture various forms of wave energy and
tune them for useful applications.
Undergraduate
engineering student Allen Hawkes, working with graduate student Alexander
Katko and lead investigator Steven Cummer, professor of
electrical and computer engineering, designed an electrical circuit
capable of harvesting microwaves.
They
used a series of five fiberglass and copper energy conductors wired
together on a circuit board to convert microwaves into 7.3V of
electricity. By comparison, Universal Serial Bus (USB) chargers for small
electronic devices provide about 5V.
"We
were aiming for the highest energy efficiency we could achieve,"
said Hawkes. "We had been getting energy efficiency around 6 to 10
percent, but with this design we were able to dramatically improve energy
conversion to 37 percent, which is comparable to what is achieved in
solar cells."
"It's
possible to use this design for a lot of different frequencies and types
of energy, including vibration and sound energy harvesting," Katko
said. "Until now, a lot of work with metamaterials has been
theoretical. We are showing that with a little work, these materials can
be useful for consumer applications."
For
instance, a metamaterial coating could be applied to the ceiling of a
room to redirect and recover a Wi-Fi signal that would otherwise be lost,
Katko said. Another application could be to improve the energy efficiency
of appliances by wirelessly recovering power that is now lost during use.
"The
properties of metamaterials allow for design flexibility not possible
with ordinary devices like antennas," said Katko. "When
traditional antennas are close to each other in space they talk to each
other and interfere with each other's operation. The design process used
to create our metamaterial array takes these effects into account,
allowing the cells to work together."
With
additional modifications, the researchers said the power-harvesting
metamaterial could potentially be built into a cell phone, allowing the
phone to recharge wirelessly while not in use. This feature could, in
principle, allow people living in locations without ready access to a
conventional power outlet to harvest energy from a nearby cell phone
tower instead.
"Our
work demonstrates a simple and inexpensive approach to electromagnetic
power harvesting," said Cummer. "The beauty of the design
is that the basic building blocks are self-contained and additive. One
can simply assemble more blocks to increase the scavenged
power."
For
example, a series of power-harvesting blocks could be assembled to
capture the signal from a known set of satellites passing overhead, the
researchers explained. The small amount of energy generated from these
signals might power a sensor network in a remote location such as a
mountaintop or desert, allowing data collection for a long-term study
that takes infrequent measurements.
The research was supported by a Multidisciplinary
University Research Initiative from the Army Research Office (Contract
No. W911NF-09-1-0539). "A microwave metamaterial with integrated
power harvesting functionality," Allen M. Hawkes, Alexander R. Katko,
and Steven A. Cummer. Applied Physics Letters 103, 163901 (2013); doi:
10.1063/1.4824473
New measurements of light from
distant supernovas could complicate cosmologists' already-frustrating
attempts to explain the mysterious dark energy that is pushing apart the
universe.
In the new analysis, scientists
combined data from 146 recently discovered supernovas with previously
published results and calculated an important cosmological parameter.
Their result is inconsistent with the simplest explanation for the
universe's accelerating expansion, which suggests that the strength of
dark energy has remained constant over the life of the universe.
If confirmed, the finding could imply
that matter in the universe will eventually be torn apart, a scenario
known as the Big Rip. But before reaching that conclusion, the
researchers say they must ferret out potential sources of error and
uncertainty in their measurements. "It's very possible, and I think
a lot of people would say likely, that one of the big measurements is
off," says study coleader Daniel Scolnic, an astrophysicist at Johns
Hopkins University.
Dark energy first made headlines in
1998, when researchers found that light from faraway supernovas was
dimmer than expected, suggesting that the universe is expanding at a
faster and faster pace. To explain this acceleration, scientists proposed
the existence of dark energy, which imbues the cosmos with a negative
pressure that pushes space outward. Most physicists suspect that dark
energy is a form of vacuum energy known as the "cosmological
constant" because its strength never varies. If so, a number
called w, which relates the pressure pushing space apart to the density
of dark energy, must equal -1.
But the new analysis, posted online October
14 at arXiv.org, arrives at a different value. Combining data from the
Hawaii-based Panoramic Survey Telescope & Rapid Response System, or
Pan-STARRS, with previous astronomical surveys, the researchers calculate
w to be -1.186. If correct, this value of w would force cosmologists to
pursue more complicated theories about the universe's expansion, in which
the strength of dark energy increases over time.
That's not happening yet. Even the
study's authors stress that they are not advocating throwing out the
cosmological constant. "My gut feeling is that w is
probably -1," says study coleader Armin Rest, an astronomer at
the Space Telescope Science Institute in Baltimore.
Rest thinks the finding most likely
results from some kind of systematic error. In a companion paper also posted
online October 14 at arXiv.org, the team determines that the largest
source of error involves differences in how the Pan-STARRS telescope and
other groups' telescopes captured the supernovas' light. Errors can also
arise from interference from dust in the Milky Way, an incomplete
understanding of supernova physics and other factors.
Glenn Starkman, an astrophysicist at
Case Western Reserve University in Cleveland, is not convinced the new
paper advances scientists' understanding of dark energy. He says the
results mostly confirm what cosmologists already know: that different
cosmological surveys disagree about parameters such as w that are crucial
to dark energy models. "It's evidence that there's discord in the
model but not yet evidence that w is less than -1," he says.
But George Efstathiou, director of
the Kavli Institute for Cosmology at the University of Cambridge,
believes that whether due to systematic error or as-yet-undiscovered
physics, the results do provide useful information. "These are very
difficult measurements to make," he says. "The more independent
data there is, the better it is for the field."
Editor's Note: This story was updated
on November 11, 2013, to correct the description of dark energy and its
connection to the constant known as w.
Spinal
stimulation: In both animal and human experiments, researchers are
using electricity to restore function to paralyzed lower limbs.
Fighting
Paralysis With Electricity
Dustin
Shillcox fully embraced the vast landscape of his native Wyoming. He
loved snowmobiling, waterskiing, and riding four-wheelers near his
hometown of Green River. But on 26 August 2010, when he was 26 years old,
that active lifestyle was ripped away. While Shillcox was driving a work
van back to the family store, a tire blew out, flipping the vehicle over
the median and ejecting Shillcox, who wasn't wearing a seat belt. He
broke his back, sternum, elbow, and four ribs, and his lungs collapsed.
Through his
five months of hospitalization, Shillcox's family remained hopeful. His
parents lived out of a camper they'd parked outside the Salt Lake City
hospital where he was being treated so they could visit him daily. His
sister, Ashley Mullaney, implored friends and family on her blog to pray
for a miracle. She delighted in one of her first postaccident
communications with her brother: He wrote "beer" on a piece of
paper. But as Shillcox's infections cleared and his bones healed, it
became obvious that he was paralyzed from the chest down. He had control
of his arms, but his legs were useless.
At first, going
out in public in his wheelchair was difficult, Shillcox says, and getting
together with friends was awkward. There was always a staircase or a
restroom or a vehicle to negotiate, which required a friend to carry him.
"They were more than happy to help. The problem was my own
self-confidence," he says.
A few months
after being discharged from the hospital, in May 2011, Shillcox saw a
news report announcing that researchers had for the first time enabled a
paralyzed person to stand on his own. Neuroscientist Susan Harkema at the University of
Louisville, in Kentucky, used electrical stimulation to
"awaken" the man's lower spinal cord, and on the first day of
the experiments he stood up, able to support all of his weight with just
some minor assistance to stay balanced. The stimulation also enabled the
subject, 23-year-old Rob Summers, to voluntarily move his legs
in other ways. Later, he regained some control of his bladder, bowel, and
sexual functions, even when the electrodes were turned off.
The breakthrough, published in The
Lancet, shocked doctors who had previously tried electrically stimulating
the spinal nerves of experimental animals and people with spinal-cord
injuries. In decades of research, they had come nowhere near this level
of success. "This had never been shown before-ever," says
Grégoire Courtine, who heads a lab focused on spinal-cord repairat the
Swiss Federal Institute of Technology in Lausanne and was not involved
with the project. "Rob's is a pioneer recovery. And what was
surprising to me was that his was better than what we've seen in rats. It
was really exciting for me to see."
The report
brought renewed hope for people living with paralysis. The prognosis is
normally grim for someone like Shillcox, who has a"motor complete" spinal-cord injury.
That level of damage usually results in a total loss of function below
the injury site.
Teams of
scientists have been working on transplanting stem cells for neural
repair and modifying the spinal cord in other ways to encourage it to
grow new neurons, but these long-term approachesremain mostly in the lab. Harkema's
breakthrough, however, produced a real human success story and gives hope
to paralyzed people everywhere. It presents a viable means of regaining
bowel, bladder, and sexual functions, and maybe-just maybe-points the way
toward treatments that could give paralyzed people the ability to walk
again.
But Harkema's
first experiment involved only one patient, and many researchers wondered
whether the improvement they saw in Summers was an anomaly. "The
next big question was, Will you ever see these things in more than one
subject?" says neurobiologist V. Reggie Edgerton of the University
of California, Los Angeles, a collaborator in the Louisville experiments.
The U.S. Food
and Drug Administration (FDA) had given Harkema the go-ahead to try the
technique in four more paralyzed people. Shillcox put his name in the
pool the night he saw the news report. He was selected, and in July 2012
he packed his wheelchair into his retrofitted Dodge Journey and drove
himself from Green River to Louisville to begin 18 months of experiments.
The circuitry
of the lower spinal cord is impressively sophisticated.
Neuroscientists believe that the brain merely provides high-level
commands for major functions, like walking. Then the dense neural bundles
in the lower spinal cord take over the details of coordinating the
muscles, allowing the brain to focus on other things. That division of
labor is what lets you navigate a party and focus on the conversation
rather than on your steps. After aspinal-cord injury, damage prevents the
high-level signal from the brain from reaching the neurons below. Yet
those neural bundles remain intact and are just waiting to receive a
signal to start the muscles working. Stimulating the lower spinal cord
with electrodes can awaken that circuitry and get it functioning,
astonishingly, without instructions from the brain.
It has been
known since the mid-1970s that direct stimulation of the spinal cord can
actually induce the legs to move as if they were taking steps, without
any input from the brain. Edgerton and other researchers have
demonstrated the concept definitively in paralyzed cats, rats, and a few
humans. But in most of these demonstrations, researchers were blasting a
large amount of electrical current into the body to force the muscles to
move. "Everyone, including us, was hung up on the idea that you have
to stimulate at this high level to induce the movement," says
Edgerton. What they missed was that the stimulation was essentially
overwhelming the neurons in the lower spinal cord and was actually
interfering with their ability to process sensory information that can
help the body move on its own.
The neurons in
the spinal cord don't only receive signals from the brain; they also
process sensory feedback from the body as the muscles move and balance
shifts. The importance of that sensory feedback gradually emerged with some animal experiments Edgerton
reported in Nature Neuroscience in 2009. The study suggested
that sensory input could actually control the motor commands produced by
the spinal cord.
Harkema, a
former student of Edgerton's, ran with that concept. In her experiments
with Summers, she stimulated his spinal cord just enough to wake it up
and then let the sensory input do its thing. "It's like putting a
hearing aid on the spinal cord," says Edgerton. "We've changed
the physiological properties of the neural network so that now it can
'hear' the sensory information much better and can learn what to do with
it."
Harkema's group
uses an off-the-shelf neurostimulation system-made by Minneapolis-based Medtronic-that's FDA approved for pain
management. The system's array of 16 electrodes is surgically implanted
in the epidural space next to the outermost protective layer of the
spinal cord. The array is then connected to a pulse generator (which
resembles a pacemaker) that's implanted nearby. Finally, the pulse
generator receives a wireless signal from a programming device outside
the body.
The array spans
approximately six spinal-cord segments, the ones generally responsible
for movement in the lower half of the body. By placing the electrodes
over them, the researchers can generate a response in the corresponding
muscle groups. Electrode 5, for example, is located near a segment of the
spinal cord that controls hip muscles. Electrode 10 is located at the
bottom of the array, over the segment that controls the lower leg.
Each of the
array's 16 electrodes can be set to act as a cathode or an anode or be
completely shut off. Stimulation intensities can range from 0 to 10.5
volts with pulses sent at frequencies ranging from 2 to 100 hertz,
although the researchers usually don't go beyond 45 Hz. Picking the right
combination of electrodes and stimulation parameters to generate a simple
response in a single muscle is relatively straightforward. But generating
a complex behavior like standing, which involves many muscle groups and a
considerable amount of sensory feedback, is far more difficult. Choosing
the right electrode configurations for standing requires both a
tremendous amount of intuition and plenty of trial and error.
"That's the challenge: to create the electrical field that's going
to give you the desired behavior," says Harkema.
On a
Wednesday in February of this year, Shillcox arrived at theFrazier Rehab Institute in downtown
Louisville for one of his first stimulation sessions. The array and pulse
generator had been implanted a few weeks before. He wore Nike sneakers
and black gym shorts, revealing thin legs atrophied from lack of use.
Shillcox joined
Harkema and her team in a large room equipped with custom rehabilitation
equipment. He wheeled himself to a three-sided stand Harkema had made out
of metal pipes that she'd bolted to a piece of plywood. Researchers taped
14 sensors to Shillcox's legs. Usingelectromyography (EMG), these sensors
would measure the electrical activity produced by his muscles and
indicate how Shillcox was responding to the stimulation. Two trainers
hoisted Shillcox from his wheelchair onto his feet and into the stand.
Then they took their positions to keep him upright-one in front of
Shillcox with both hands pushing against his knees and the other behind,
steadying his hips. Shillcox held onto the stand with his hands, and a
bungee cord supported him from behind.
That day,
Harkema planned to test new stimulation configurations to see whether one
of them would allow Shillcox to stand on his own. She took a seat in
front of a screen displaying the EMG signals while two other researchers
helped monitor the data from other screens. To start the session, Harkema
called out the electrode settings: "1+, 2+, 3+, 9+, 14+, 12+, 13+,
6+, 7-, 8-, 4-, 10-." This configuration used 12 of the 16 electrodes,
8 of them as anodes (positively charged) and 4 of them as cathodes
(negatively charged). Harkema instructed her team to set the pulsation
frequency at 30 Hz and the initial intensity at 1 V and to ramp
up by a tenth of a volt at a time. "Left independent," a
trainer called out when the stimulation reached 1.5 V.Shillcox bore
his weight on his left leg without assistance for about 30 seconds.
Harkema jotted
in her lab book and instructed the team to turn off electrode 10, the one
targeting Shillcox's lower leg. "Going to zero," a researcher
called out. He powered down the system, punched in the new electrode
configuration without electrode 10, and ramped it up again. At 2.6 V,
Shillcox's knees buckled. "It shot me out," Shillcox said. The
electrodes hadn't sent the signal to the legs to stand straight but had
twitched his knees forward instead. The stimulation pattern and
parameters weren't quite right.
Harkema tried
more configurations, but each time Shillcox felt nothing until Harkema
hit a particular voltage threshold, at which point Shillcox's knees would
give way. After 75 minutes, on the 10th and last try, Harkema removed the
bungee supporting Shillcox from behind. The muscle activity on the EMG
monitors skyrocketed. He'd been balancing so perfectly with the bungee
cord that he hadn't been getting enough external sensory information to
activate his muscles, Harkema concluded, so there had been little input
flowing back to the lower spinal cord. She instructed her team to devote
the next few sessions to the last electrode pattern of the day, but
without the bungee.
The
technological limitations of the stimulation system make these trials
unnecessarily difficult. Each time Harkema changes the configuration of
electrodes, she has to turn off the electric field they generate and
start over at 0 V. It's a safety feature of this off-the-shelf
stimulator, but it destroys the body's neural momentum. "You can get
really close, and you think the person is almost standing independently,
and if you could just shift the field a little you would have it. But you
can't. You have to go to zero. And then everything starts over,"
says Harkema. The limitation makes it especially difficult to induce a
stepping motion in her patients. "It's a left-to-right problem. If
we get the right leg to step, the left is doing nothing," she says.
It doesn't help
that there are something like 4.3 x 107 possible electrode patterns
she can try and that each can be tried with a range of frequencies and
voltages. Without an algorithm to help her choose parameters, Harkema
must rely on her experience, some limited neural mapping data, and what
she sees on her monitors. "I have to look at the EMG data whizzing
by and then make decisions about what I can change out of these 4.3 x
107 combinations to get it better," says Harkema. She's gotten
pretty good at making adjustments, but she acknowledges that no one can
fully interpret the nuances of all that EMG data.
To do
better, Harkema has enlisted the help of a handful of engineers who
say they can build a stimulation system specifically for her research. At
the California Institute of Technology, mechanical engineer Joel Burdick is developing a
machine-learning algorithm that aims to take some of the guesswork out of
choosing stimulation parameters.
The algorithm
is based on statistical methods that predict the patient's likely
response to stimulation patterns-even those that haven't been tested yet.
The prediction part is crucial because there's no way to try out all the
options: There are millions of electrode configurations, and every
patient is different. And just to make things even more complicated,
patients' spinal cords change during the course of the stimulation
experiments. "The amount of time it would take to test that space is
beyond a patient's lifetime," says Burdick. So the algorithm has to
learn quickly. It must apply reasonable stimulation patterns and then use
the patient's EMG responses to choose better configurations.
Burdick's team
is working with Edgerton's lab at UCLA to test the algorithm on paralyzed
rats. The researchers are starting simply, using just a couple of
electrodes and trying to maximize the response in a particular muscle.
The first step is to make sure the algorithm is making reasonable
decisions. The team has also begun a small human pilot study, Burdick
says.
Meanwhile, John Naber, an electrical engineer at the
University of Louisville, and a team of engineers are developing a
stimulation system that would give Harkema independent control of all 16
electrodes in Medtronic's array. The design would allow her to transition
from one configuration to the next without shutting off the current. The
team is building a new pulse generator using off-the-shelf components,
and they've already written the code and roughed out a design. The
challenge, Naber says, will be getting it approved by the FDA in a
reasonable amount of time. "It's not like a commercial integrated
circuit or product, because of the FDA requirements for human
implants," Naber says.
The lingering
question is whether Medtronic's 16-electrode array is the best one for
Harkema's work. It was designed to treat pain, so the current diffuses
rather broadly. Yu-Chong Tai, an electrical engineer at
Caltech, thinks that an array with smaller electrodes arranged more
densely might offer the precise stimulation needed after spinal-cord
injury. The prototype he's testing in rats has 27 electrodes arranged
over a 2-centimeter-long array. A human version would be similar in size
to Medtronic's (about 5 cm long) but would contain hundreds of
electrodes. Of course, more electrodes would mean exponentially more
configuration options. "If we give them more electrodes, they will
need a smart algorithm," says Tai.
Until Naber and
Tai's prototypes can be approved by the FDA and Burdick's algorithm can
be fine-tuned, the Medtronic system will have to suffice. That may limit
what Harkema can achieve when she puts Shillcox and her other research
subjects on the stimulator, especially in terms of stepping. Even so,
Shillcox has reason to hope that the experiments will boost his quality
of life. Rob Summers, Harkema's first subject, says his perspective on
life has greatly improved since he regained bladder, bowel, and sexual
functions. "This project has given me my freedom back," he
says.
Research
subjects No. 2 and No. 3 have completed their initial trials. Like
Summers, both were able to stand while on the stimulator, as Harkema and
her colleagues reported at a Society for Neuroscience meeting in 2012.
The researchers have not publicly announced whether other voluntary
movement and physiological functions, such as bladder control, have
returned for those individuals.
Shillcox-subject
No. 4-remains hopeful, but he's trying to keep his expectations
realistic. "I don't want to be too optimistic, and I'm trying to be
prepared for no results at all," he says. "I hope that whatever
they find from this research will at least benefit other people."
Shillcox will likely complete his training by the end of the year, and
Harkema says she cannot yet publicly reveal their preliminary results.
Whatever the medical benefits ultimately prove to be, working with
Harkema as a pioneer on an experimental treatment for spinal-cord injury
has boosted Shillcox's confidence around others. "I have no problem
asking for help now," he says.
This article
originally appeared in print as "An Electrifying Awakening."
About the Author
Emily Waltz, a
freelance journalist based in Nashville, frequently writes about biotechnology
for IEEE Spectrum. Last year she strapped on an assortment of
health-monitoring gadgets for an article about the "quantified self" movement
The research is the first of its kind to evaluate the energy
production of solar panels oriented in different directions. Pecan Street
analyzed 50 homes in the Austin, Texas area. Some had only south-facing
panels, others had west-facing panels, and some had both.
South-facing panels produced a 54 percent peak reduction overall,
while west-facing solar PV panels produced a 65 percent peak reduction.
"There's no other residential demand response tool generating 60
percent reductions," said Brewster McCracken, CEO of Pecan Street.
"Those are pretty extraordinary peak reductions."
When the data was normalized for a 5.5-kilowatt system, the panels
turned to the west generated nearly 50 percent more electricity during
peak demand hours than did their southern-facing counterparts.
Homes with west-facing systems also produced slightly more
electricity, with those panels producing 37 percent of total daily
electricity use, compared to 35 percent for the south-facing panels.
During times of peak demand, which is defined as 3 p.m. to 7 p.m. in
Texas's ERCOT territory, 84 percent of electricity in west-facing systems
was used in the home.
The information could help inform utility rebate programs for rooftop
solar panels and demand response programs. Most homes currently have
south-facing panels. For the research, Pecan Street paid a premium to
participants to induce them to turn their panels westward. If more
utilities were to move to dynamic pricing models, where power cost more
during days of high peak demand, west-facing panels could potentially be
more attractive to certain households with high peak loads.
The next round of research will also include information about the
pitch of the roof. Panels on flat roofs tend to have higher rates of
electricity generation, but most homes in the U.S. have pitched roofs, as
did all of the participants in the first study. Pecan Street will also
look beyond Austin in the next stage of the study. McCracken said there
are plans to include homes in Colorado, Dallas and potentially
California.
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A coalition of eight states
announced plans Thursday to boost the use of electric cars and other zero
emission vehicles, promising incentives and an improved network of
fueling stations to encourage consumers to buy the vehicles and prompt
manufacturers to produce more of them.
The eight governors who signed the agreement,
including Maryland Gov. Martin
O'Malley (D), hope to put at least 3.3 million zero emission vehicles
on their roads by 2025. To accomplish that, they pledged to install more
electric charging stations, introduce or continue tax breaks for
consumers and add such vehicles to government fleets. Some other states
have similar incentives, though they did not join the group.
Collectively, the eight states - California,
Connecticut, Maryland, Massachusetts, New York, Oregon, Rhode Island and
Vermont - represent about 23 percent of the U.S. auto market, according
to information the group released Thursday.
"We think it's doable," said Mary
Nichols, chairman of the Air Resources Board in California, the biggest
market in the group. "The market is moving fast. It started from
zero and it accelerated very quickly."
Nichols and others said the greatest obstacle to
overcome is consumer resistance to new technology. Buyers must be
convinced that the vehicles will work for them, she said, a process that
usually requires seeing them on the road or in a neighbor's driveway -
not just in an advertisement.
"Once we are able to get the word out to
consumers that there is an infrastructure out there, and [it is] all over
the state ... we'll be able to encourage a greater desire to get an
electric vehicle in Maryland," said Samantha Kappalman, a
spokeswoman for O'Malley.
U.S. motorists bought about 52,000 electric cars in
2012, up from about 17,000 in 2011, according to the group. More than
40,000 plug-in cars were sold in the first half of 2013. In addition to
all-electric cars, the group wans to encourage production and purchase of fuel cell vehicles,
which run on hydrogen, and plug-in hybrids ,
which have both electric and gasoline engines.
Maryland wants to put 60,000 zero emission vehicles
on its roads by 2020, Kappalman said, and will add another 110 to 160
public charging stations to the 430 that exist. In addition to the $7,500
federal tax credit available to buyers of such vehicles, the state offers
a $1,000 excise tax credit, a $400 tax credit for any equipment purchased
and access to HOV lanes, she said.
In 2012, 1,764 electric vehicles were sold in
Maryland, up from 227 in 2011. This year's sales will surpass last
year's, she said.
Volkswagen's
first foray into the realm of all-electric cars is now making it world
debut in (where else?) the only U.S. state guaranteed to have it. The
2015 e-Golf bowed this week at the 2013 Los Angeles Auto Show, revealing
a handful of significant exterior- and interior-design changes compared
with the regular Golf ,
but also an entirely new, zero-emissions powertrain. The plug-in
hatchback becomes the first VW in the U.S. to get standard LED
headlights, as well as complementary C-shaped LED daytime running lights,
a unique grille with blue accenting and aerodynamic 16-inch alloy wheels
with low-rolling-resistance tires. Inside, the primary differences are
additional blue accents and a power display in the instrument panel that
shows the state of the electric powertrain; that's in addition to a gauge
that shows how much energy remains in the battery and a color display
showing the range. Available upgrades include a leather-wrapped steering
wheel, faux-leather upholstery and a touch-screen navigation system.
The e-Golf's
electric motor uses a lithium-ion battery and makes 115 horsepower and
199 pounds-feet of torque. It's teamed with a single-speed transmission
and good for a 10.4-second zero-to-60 mph time and 87 mph top speed. The
automaker says recharge time is less than four hours on a 220-volt
outlet, 20 hours on a conventional household outlet and just a half-hour
at a DC fast-charge station. Check out the photo gallery below; Cars.com
photos by Evan Sears.
Future Energy eNews is
provided as a public service from Integrity
Research Institute, a Non-Profit dedicated
to educating the public on eco-friendly emerging energy
technologies.
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