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Solar combo generator heats and powers.

January 20, 2011
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Solar combo generator heats and powers | Green Tech – CNET News.

A new type of solar thermal system for homes that can provide heat, hot water, and electricity is being tested in Boulder, Colo., over the next few months.

Cool Energy says its SlowFlow system could provide the average U.S. home with 80 percent of its heat, 100 of its hot water, and 60 percent of its electricity needs.

It’s being developed with help from the National Science Foundation, the Department of Energy, and electricity and natural gas giant Xcel Energy.

The system consists of solar collectors, a Stirling engine, a hot water heater, a space heater, an insulated storage tank, and the SolarSmart Controller, a computer with networked communications

The SolarSmart Controller uses weather, ambient temperature, building temperature, and sunlight data to determine the device’s most effective usefulness for a given day. If, for example, it’s cold and overcast outside and its building’s internal temperature is below a given desired temperature, the device would generate its effort to heating the building. On warm and sunny days, it would direct itself to generate electricity instead.

But the centerpiece tech of the system, which won the 2009 Cleantech Open Sustainability Award for the Rocky Mountain region, is Cool Energy’s SolarHeart engine. The proprietary Stirling engine was developed by Cool Energy to efficiently convert solar thermal energy or waste heat into electricity. When tested in the lab over a wide array of temperature and solar conditions, the device’s SolarHeart engine was able to generate more than 2,000 watts of electricity, and achieve more than 16 percent efficiency for thermal-to-electrical conversion, according to Cool Energy statistics.

The complete Slow Flow system minus its solar collectors, which are located on the roof of the building.

(Credit: Cool Energy)

A successful solar multi-use generator might allow customers to recoup their investment in the device more quickly compared to solar panels that provide electricity only. It might be especially effective in climates where homeowners need home heating oil or propane to heat their homes in winter, and electricity-guzzling air conditioners to cool their homes in summer.

Of course, the field test will offer more insight on this system’s true real-world capabilities. And while this is certainly an innovative green tech product idea, Cool Energy is not the first to use a solar-driven Stirling engine.

Tessera Solar and Stirling Engine Systems have been testing a large-scale solar system that uses mirrored parabolic dishes that track the sun and heat hydrogen gas-filled pistons in a Stirling engine to generate electricity.

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How Starbucks Saves Millions per Year in Energy from LED Lighting | Business |

December 6, 2010
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How Starbucks Saves Millions per Year in Energy from LED Lighting | Business |


Starbucks recently finished replacing nearly all of its incandescent and halogen lighting with LEDs during a two-year roll-out to over 7,000 company-owned stores, most in the United States and Canada, but with some in Europe and Asia. This is the largest deployment yet of LED technology in an application that is very sensitive to the quality of light; Starbucks’ success proves that the new digital lighting is ready for mass install.

Jim Hanna, Director of Environmental Impact for Starbucks confirmed that the LED lighting program is on target to slash consumption by more than 80 percent compared to existing lighting. My back-of-the envelope calculations [see notes below] found that

• Each LED light bulb saves approximately $30 annually in energy costs and eliminates the equivalent CO2 as half a barrel of oil;
• Each 1,000 square foot store on average would save nearly $600 annually and eliminate the equivalent CO2 as 10 barrels of oil

To capture these impressive benefits, for both the bottom-line and the environment, it took more than replacing a light bulb. When Starbucks was examining which energy efficiency projects to deploy in its stores, lighting was an obvious choice, since retailers consume a large amount of energy on lighting to provide ambiance and to showcase products.

But Starbucks had already installed energy-efficient fluorescents in many areas of its stores. The remaining halogen and incandescent lights were in its beverage and sitting areas. The soft, warm light provided by incandescent bulbs was critical to creating an inviting experience. And halogens were used to highlight products. Fluorescent was a poor fit in these areas due to its inferior color rendition. Although CFLs are prevalent in offices, older and inefficient lighting technology is common in many retail and other high-end applications.

Starbucks investigated LED lights and appreciated the low energy use and the quality of light, but LED products on the market at the time required replacing both the light bulb and fixture driving costs up considerably.

Rather than wait for the price of technology to drop, Starbucks reached out to its partner, General Electric. Hanna said, “GE worked with us to develop a LED light bulb that provides similar output as incandescent but uses a fraction of the electricity. GE kept retrofit costs low by designing a bulb that could fit the track lighting and recessed cans that were already installed.”

The roll-out after initial trials proceeded smoothly. It is too early to confirm the LED longevity, but Starbucks is confident in its approach. Hanna explained, “The GE partnership reduces the risk of new technology should issues surface.” The Starbucks case study illustrates that emerging technology can provide significant savings and is worth the extra effort to make new technology work for your requirements.

Hanna agrees with the U.S. Department of Energy assessment that “LED usage will accelerate … since … no other lighting technology offers as much potential to save energy and enhance the quality of our building environments.” Starbucks achieved a notable LED milestone, but that’s one record that Starbucks is happy to see beaten. Will your facilities be the next LED winner?


I did some calculations after my discussions with Jim Hanna to estimate just how much money Starbucks is saving due to its LED retrofit. Here’s what I found:

• A new LED bulb requires 7 to 10 watts, depending on light output. It replaces 50 to 60 watt bulbs, either incandescent or halogen. [Source: Starbucks interview]

• Common practice in retail is to leave some lighting on 24/7 for security and advertising. For this calculation it was assumed that one-third of lighting remains on 24/7, while the rest of the bulbs were lit during operating hours. [Source: Author visits to several stores]

• According to the U.S. Energy Information Administration, the average cost of electricity in 2010 in the U.S. is 10 cents per kilowatt-hour.

• The savings estimate did not consider reduced maintenance which given the exceptionally long life of LED would increase savings and accelerate payback. • Carbon savings were estimated using the EPA’s Clean Energy calculator.

• About 50 percent of the retail square footage is lit by LED, the other portion of the store is lit by CFL. [Source: Starbucks interview]

• 258,000 green bulbs were deployed in US and Canada to date (both LED and CFL bulbs) [Source: Starbucks interview]

• Company owned stores used 6.8 KWH / square foot / month on average in 2008 prior to LED deployment. [Source: Starbucks CSR 2009 Report] [PDF]

• The new LED lights reduced total store energy consumption by 7 percent when compared to the baseline. [Source: Starbucks interview]

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New button battery generator makes power by just being in your pocket!

December 3, 2010
After its closure, Zwevegem Electric Power Pla...
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Small Vibration-driven Generator Developed for Replacing Button Batteries — Tech-On!.

A Japanese university researcher developed a small-size vibration-driven generator that measures approximately 2 x 3 x 12mm and can output a power of 1.56mW with a vibration of 357Hz.

The energy density of the generator, which was developed by Toshiyuki Ueno, associate professor at Kanazawa University, is about 22mW/cm3. It is about 20 times higher than the energy density of normal small-size vibration-driven generators, which is about 1mW/cm3.

“The energy density is high enough to replace a button battery,” Ueno said.

He is planning to apply the generator to tire pressure monitoring systems (TPMSes) for automobiles and mobile devices.

As a power generating element, Ueno used a magnetostrictive material called “Galfenol” (Fe81.4Ga18.6), which is an alloy of iron (Fe) and gallium (Ga) and has a large magnetostriction effect. Magnetostriction effect is a phenomenon in which the shape of an object changes due to magnetization. In the case of Galfenol, its magnetostriction effect is about 300ppm (a 1km-long bar would extend by about 300mm).

To generate electricity, Ueno used inverse magnetostriction effect, which is the converse phenomenon of magnetostriction effect. Inverse magnetostriction effect is a phenomenon in which the application of stress changes magnetization. In the case of Galfenol, its magnetic flux density decreases by up to more than 1T when compressional stress is applied. And the change in magnetic flux generates an induced voltage.

Galfenol was developed by the US Naval Research Laboratory (NRL) in 1998. But this is the first time that it has been used for a vibration-driven generator, Ueno said.

Galfenol is a ductile material. Therefore, it can be easily processed by machines, and it does not easily break when warped. Piezoelectric elements, which are normally used for vibration induced power generation, are made of a ceramic, which is a brittle material.

Terbium (Tb), dysprosium (Dy) and Terfenol-D, which is an iron-based super-magnetostrictive material with a magnetostriction effect of about 1,000ppm, have large magnetostriction effects. But they are also brittle materials.

This time, Ueno created a structure that is small but can generate a large amount of electricity by taking advantage of the ductility of Galfenol. Specifically, one ends of two long and thin magnetostrictive elements are fixed, and weights are added to the other ends (parallel beam structure). To output electricity, coils are made by winding thin electric wires around the magnetostrictive elements.

When the weights vibrate up and down, bending deformation occurs to the two magnetostrictive elements. At this point, a compressive force is applied to one element, and a tensile force is applied to the other element.

When the weights are moving up and down, the compressive force and the tensile force are alternately applied to each of the two elements, periodically changing the magnetic flux. This time variation generates induced voltage on the coils, and electric power can be efficiently output.

“Because Galfenol is a ductile material, even the thin rod-shaped structure does not easily break,” Ueno said.

The dimensions of the magnetostrictive element are 1.0 x 0.5 x 10mm, and it is equipped with a magnet that is 2mm in diameter and 2mm in length for bias magnetization.

Moreover, Galfenol features an excellent thermal property. Its Curie temperature is as high as 700°C, and its performance does not change much within the temperature range of -200 to 200°C, Ueno said. Therefore, Galfenol is suited for use in places where change in environment is fast and violent.



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How Loud is a Wind Turbine?

November 23, 2010

How Loud is a Wind Turbine? | GE Reports.

Because wind turbines are such a great source of clean, renewable energy, they’re usuallygreeted with a great deal of enthusiasm. But some complaints have been made that they can cause too much noise for residents living within a mile of the blades.

So just how noisy are these turbines?

The closest that a wind turbine is typically placed to a home is 300 meters or more. At that distance, a turbine will have a sound pressure level of 43 decibels. To put that in context, the average air conditioner can reach 50 decibels of noise, and most refrigerators run at around 40 decibels.

At 500 meters (0.3 miles) away, that sound pressure level drops to 38 decibels. In most places, according to Keith Longtin of GE Global Research, background noise ranges from 40 to 45 decibels, meaning that a turbine’s noise would be lost amongst it. For the stillest, most rural areas, Longtin says the background noise is 30 decibels. At that level, a turbine located about a mile away wouldn’t be heard.

For a complete run down of louder-than-a-fridge but quieter-than-a-blender context points, check out the graphic


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Philadelphia Eagles Home Turf Will Be Powered With On-Site, Renewable Energy By September 2011

November 19, 2010
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Lincoln Financial Field Will Be Powered With On-Site, Renewable Energy By September 2011 – Philadelphia Eagles.

The above link has the video of the presentation ceremony with Ron Jawarski.

The Philadelphia Eagles today announced a plan to power Lincoln Financial Field with a combination of onsite wind, solar and dual-fuel generated electricity, making it the world’s first major sports stadium to convert to self-generated renewable energy.

The Eagles have contracted with Orlando FL-based SolarBlue, a renewable energy and energy conservation company, to install approximately 80 20-foot spiral-shaped wind turbines on the top rim of the stadium, affix 2,500 solar panels on the stadium’s façade, build a 7.6 megawatt onsite dual-fuel cogeneration plant and implement sophisticated monitoring and switching technology to operate the system.

Over the next year, SolarBlue will invest in excess of $30 million to build out the system, with a completion goal of September 2011. SolarBlue will maintain and operate the stadium’s power system for the next 20 years at a fixed annual price increase in electricity, saving the Eagles an estimated $60 million in energy costs.

The Eagles and SolarBlue estimate that over the 20-year horizon, the on-site energy sources at Lincoln Financial Field will provide 1.039 billion kilowatt hours of electricity – more than enough to supply the stadium’s power needs – enabling an estimated four megawatts of excess energy off-peak to be sold back to the local electric grid.

Against a backdrop of trees symbolizing the Eagles’ commitment to reforestation, the Luries invited special guests to join them in signing the Go Green! Team’s Declaration of Energy Independence, which “seeks to create a better living environment by reducing the world’s dependence on fossil fuels.”

The greening of Lincoln Financial Field is a significant step by a major sports franchise to achieve that goal. The energy to be generated by on-site renewable sources is comparable to the annual electricity usage of 26,000 homes. Engineers at Solar Blue estimate that converting the stadium to renewable energy will eliminate CO2 emissions equivalent to 500,000 barrels of oil or 24 million gallons of gasoline consumed annually. That equates to removing the carbon emissions of 41,000 cars each year.

“The Eagles’ plan for Lincoln Financial Field represents one of the most extensive renewable energy commitments by any major facility,” said Lee Maher, Chairman and CEO, SolarBlue. “The energy plan will utilize the most technologically advanced wind turbines and solar panels. With this installation, we anticipate that many businesses will see the benefits of renewable energy and be inspired to emulate the Eagles’ bold leadership.”

Beyond the substantial environmental advantages, the Eagles’ renewable energy plan will create hundreds of jobs for the Philadelphia area.  SolarBlue anticipates directly employing 200 local people during the year-long design and installation phase. One-quarter of these jobs will be permanently maintained over the 20-year operational horizon.  In addition, the project will generate approximately 600 indirect jobs in the surrounding region as a result of Solar Blue’s commitment to utilize local contractors, vendors and suppliers, as available.

Philadelphia Mayor Michael Nutter stated, “The Philadelphia Eagles have been great corporate citizens for many years, most specifically working with disadvantaged youth throughout the City. But we also know the Eagles to be green; they don’t just wear green, they sincerely believe in the concept of responsible environmental stewardship. We appreciate their commitment to an issue that is at the core of the City’s Greenworks Philadelphia Plan, to become the Greenest City in America. Today’s announcement will help reduce the City’s carbon footprint, create hundreds of much needed green jobs and put our City on the world stage. This type of forward thinking will serve as an excellent example to every organization that wants to play a role in strengthening our local economy while helping the environment.”


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Society build on non-renewable sources cannot last.

November 18, 2010
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November 17, 2010
We end today’s show with a figure who’s been called the poet-philosopher of the ecology movement. Author and activist Derrick Jensen has written some 15 books critiquing contemporary society and the destruction of the environment. In 2008, he was named one ofUtne Reader magazine’s 50 visionaries who are changing the world. Among his books, A Language Older than WordsEndgameWhat We Left Behind, andResistance Against Empire. Derrick Jensen lives in Northern California. I had an extended conversation with him in San Francisco just a few weeks ago. Today we play part one of that discussion. I began by asking Derrick Jensen about the title of his book, what he means by Deep Green Resistance

DERRICK JENSEN: I think a lot of us are increasingly recognizing that the dominant culture is killing the planet. And we can argue about whether, you know, there will be a few bacteria left or whatever, but when 90 percent of the large fish in the oceans are gone, when there’s six to ten times as much plastic as phytoplankton in parts of the ocean, when there’s dioxin in every mother’s breast milk, when rates of extinction are a thousand to ten thousand times background rates, you know, it’s sort of just playing with numbers to talk about whether it’s killing the planet or simply mortally wounding it. And I think it’s very important for us to start to build a culture of resistance, because what we’re doing isn’t working, clearly.

I ask a lot of times why it is that environmentalists, as environmentalists—I include myself as a front line activist—I ask why it is that we lose so often. And there’s a couple of answers that really speak to me. One of them is that I think a lot of us don’t really know what it is we want, and we don’t think strategically very much.

So, I don’t think that a lot of us think very clearly about what it is exactly we want. I do know what I want, which is I want to live in a world that has more wild salmon every year than the year before, and I want to live in a world that has less dioxin in every mother’s breast milk every year than the year before, and a world that has more migratory songbirds every year than the year before.

There’s this absolutely extraordinary book called The Nazi Doctorsby Robert Jay Lifton, and in this book he describes how it was that men—people, but men in this case—who had taken the Hippocratic Oath could work in Nazi death camps. And what he found was that many of the doctors who worked in the death camps actually cared very deeply for the health of the inmates. And, you know, Mengele was, you know, horrible. But a lot of the sort of straight-line doctors they would do whatever they could. They would give them an extra scrap of potato to eat or—the inmates. Or they would hide them from the selection officers who were going to kill them. Or they would—

AMY GOODMAN: To keep their experiments going?

DERRICK JENSEN: No, no, no. They would hide them from the selection officers who were going to kill them. They would do this to protect the inmate for that day. They would put them to bed, you know. They would actually do everything—if they were in pain, they would give them aspirin to lick. They would do what they could to help, except for the most important thing of all, which is they wouldn’t question the existence of the entire death camp itself. So they would find themselves working within the rules, however they could, to try to improve conditions marginally. And in retrospect, of course, that’s just not sufficient. And as a longtime activist, I see myself and other activists doing the same thing, that what we do is we do everything that is allowed by those in power to attempt to stop their destruction. But the problem is, whenever we figure out a way to use their rules to actually stop them, they change the rules.

AMY GOODMAN: Derrick Jensen, deep green resistance, what form should it take?

DERRICK JENSEN: Sometimes I get accused of being the violence guy, because I talk about the capital of fighting back. But I don’t ever think that’s really fair, because I really consider myself the everything guy, that I want to put everything on the table and talk about, you know, all forms of resistance, and decide whether they’re appropriate or inappropriate for use. I don’t want to go in prejudging.

I think, for example, one man, all by himself, almost stopped World War II: Georg Elser. He was a trade unionist who didn’t like what Hitler was doing to the trade unions. So he got a job in a mine, stole some explosives, and he knew every year, on the anniversary of the Beer Hall Putsch, that Hitler would give a speech, and from 7:30 to 8:30, so he set a bomb to go off at 8:20, 1939. And unfortunately, because of the weather, Hitler gave his speech from 7:00 to 8:00 and left 20 minutes early. You know, and we can certainly parse out cases where we think it’s appropriate to have militant response or non-militant response, but something I want to say about all that is that that’s not the real question for me. The real question is the distinction between those people who do something and those people who do nothing.

And I want to emphasize, too, that, for example, even the IRA at its strongest, or the U.S. military, for that matter, only about two percent of the people ever pick up weapons. Most of the people are doing support work. I mean, Maud Gonne was central to the Gaelic literature revival. She wrote plays, and she sang. And her son became the chief of staff of the IRA and later formed Amnesty International. I guess all I’m trying to say is that we need to ask ourselves, what do we want, and then to ask ourselves, how are we going to get there? And those are not rhetorical questions.

AMY GOODMAN: But it’s easy resorting to violence. It comes from the model of the establishment. They like to say war is the last resort, but so often it is the first approach that the establishment takes, led by the military—and sometimes not led by. They’re the ones that know the suffering the most, so it’ll just be the civilian government. But do you want to take that model of violence as a way—even a way to deal? I mean, imagine if you took violence off the table, you didn’t answer by saying they’re doing violence, so it has to be met with violence. I mean, from your life, you talk a great deal about your own growing up and the role that violence played and how incredibly destructive it was. Why don’t we go there? Why don’t you talk about how you came to be Derrick Jensen? What has shaped you, influenced you, both negatively and positively? But this issue of violence that is so real, unfortunately is not a metaphor in your life.

DERRICK JENSEN: Well, yeah. My father’s extremely violent—was, presumably still is. I haven’t talked to him for years. And he broke my sister’s arm. My brother has epilepsy from blows to the head. He raped my mother, my sister and me. And we can talk about the negative effects of that. You know, many years of therapy. And we can talk about, you know, the years of insomnia and the night terrors and all that. There are a few people—I know you’re not saying this—but there are a few people who say, “Gosh, he just wants to fight back because he’s projecting his own, you know, helplessness as a child onto larger culture. You know, he hates the big daddy now, the Uncle Sam daddy.” And once again, I’m not suggesting you were suggesting that—and that’s always been sort of a kind of a ridiculous critique, I’ve thought, because if my father would have been perfect, 90 percent of the large fish in the oceans would still be gone, and Coca-Cola would still be destroying aquifers in India, and 25 percent of all women in this culture would still be getting raped. And, you know, we could go all down the list.

But one of the things that he did do is he helped me get a framework on which I could start to understand the larger movements of power in the culture and also the larger ways that discourse supports power. And one of my favorite examples of this is the psychiatrist R.D. Laing came up with the three rules of a dysfunctional family, which are also three rules of a dysfunctional culture. And Rule A is don’t. Rule A-1 is Rule A does not exist. And Rule A-2 is never discuss the existence or nonexistence of Rules A, A-1 or A-2. So what this means, you know, within the sort of corporate news media, is you can talk forever about Dancing with the Stars or, whatever spectacle we want to talk about, but talking about the things that really matter, as in the real physical world, or as in stopping atrocities, against women, and so, that’s one of the things I got from my childhood or that I was able to sift out from my childhood or refine from my childhood is that understanding of how abusive dynamics work.

AMY GOODMAN: Derrick, what is the influence of Native Americans in your writing, in your work, in your activism?

DERRICK JENSEN: It’s another great question. And I have tried not to romanticize them, which is another form of objectification. And what I do know is I know that the Tolowa Indians, on whose land I now live up in way northern California, they lived there for at least 12,500 years, if you believe the myths of science. And if you believe the myths of the Tolowa, they lived there since the beginning of time, using a myth as stories that we tell ourselves that make the world fit together. So, in any case, the Tolowa lived there for at least 12,500 years. And when the dominant culture got there 180 years ago, the place was a paradise. I mean, salmon runs so thick that you could hear them for miles before you’d see them. I learned this recently, that up in Canada, one of the things that people would do for fun when the salmon runs came in is they would throw a little pebble into the water, and they would see how long it would float on the backs of fish before it would hit the ground, because there were so many fish that the rock couldn’t make its way down. And I’m lucky if I see a half-dozen salmon in a year at this point.

One of the things that abusers constantly want us to do is to believe that there is only one way to be, which is theirs. And this is true—you know, there’s the great line—I think it was Václav Havel—the struggle against oppression is a struggle of memory against forgetting. And one of the things we need to remember is that there have been other ways of living that have been sustainable. The Tolowa lived there for 12,500 years, which is sustainable by any realistic measurement. And they didn’t do it because they were too stupid to invent backhoes. You know, why? Why? How did they look at the world differently that allowed them to live? It wasn’t because they were primitives. It wasn’t because they were savages. What did they have? They had social strictures in place.

AMY GOODMAN: Derrick, you’ve written, “Civilization is not and can never be sustainable.”

DERRICK JENSEN: Yeah. Several years ago, I was riding around in a car with a friend of mine, George Draffan, with whom I’ve written a couple books. And I was just making conversation. I said, “So, George, if you could live at any level of technology that you want to, what would it be?” And he was not in a very good mood that day, and he said, “That’s a really stupid question, Derrick, because we can fantasize whatever we want, but the truth is there’s only one level of technology that’s sustainable. And that’s the Stone Age. And we’ll be there again some day. And the only question really is, what’s left of the world when we get there?”

It doesn’t take a rocket scientist to figure out that any way of living that’s based on the use of non-renewable resources won’t last. In fact, I would say it takes anybody but a rocket scientist to figure that out. And likewise, it doesn’t take someone who’s very smart to figure out that if every year there are fewer salmon returning than the year before, that eventually there won’t be any left. I mean, there were so many passenger pigeons that they would darken the sky for days at a time. There were six times as many passenger pigeons than all the birds in North America. Do we know why there aren’t any penguins in the northern hemisphere? The great ox? They were destroyed. And my point is that any way of life that’s based on the hyper-exploitation of renewable resources won’t last. In the book, What We Leave Behind, what we came to for a definition of “sustainability” is leaving the physical world in a better place than when you were born, that the world is actually a better place because you were born.

A lot of definitions of “civilization” that we see are not really very specific, and the definition I like the most, which is defensible both linguistically and historically, is civilization is a way of life characterized by the growth of cities—once again, defensible both linguistically and historically. A city, I’ve defined as people living in numbers large enough to require the importation of resources. And what this means, that the Tolowa didn’t live in cities, because they didn’t require the importation of resources. They didn’t live in cities; they lived in villages, camps, and they ate salmon. They ate what the land gave willingly.

And two things happen as soon as you require the importation of resources. One is that your way of living can never be sustainable, because if you require the importation of resources, it means you denuded the land base of that particular resource, and as your city grows, you’ll need an ever larger area. And the other thing it means is that your way of life must be based on violence, because if you require the importation of resources, trade will never be sufficiently reliable, because if you require the importation of resources and the people in the next watershed over aren’t going to trade you for it, you’re going to take it. And one of the problems with this whole system is that destroying your land base gives you a competitive advantage over the other cultures who don’t. The forests of North Africa went down to make the Phoenician and Egyptian navies. And if you destroy your land base, if you don’t care about the future, you can turn this into immediate power and then use it to conquer, and which is something you have to do, because you’ve destroyed your own land base. And as time goes on, you have to keep expanding. And that’s not a very good idea on a finite planet.

AMY GOODMAN: Derrick Jensen—part two of our conversation coming up later this week—author of Resistance against EmpireA Language Older than Words,Deep Green Resistance, coming soon.

Amy Goodman is the host of the nationally syndicated radio news program, Democracy Now!.


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Sandia National Laboratory may get nuclear fusion to work….soon.

November 15, 2010
A homemade IEC fusion reactor created by a hig...
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Sandia effort images the sea monster of nuclear fusion: the Rayleigh-Taylor instability – Sandia News Releases.

More accurate simulations could lead to “break-even” fusion in foreseeable future

ALBUQUERQUE, N.M. — A new X-ray imaging capability has taken pictures of a critical instability at the heart of Sandia’s huge Z accelerator. The effort may help remove a major impediment in the worldwide, multidecade, multibillion dollar effort to harness nuclear fusion to generate electrical power from sea water.

“These are the first controlled measurements of the growth of magneto-Rayleigh-Taylor [MRT] instabilities” in fast Z-pinches, said project lead Daniel Sinars.

MRT instabilities are spoilers that arise wherever electromagnetic forces are used to contract (pinch) a plasma, which is essentially a cloud of ions. The pinch method is the basis of the operation of Z, a dark-horse contender in the fusion race.


Z Machine PinchThis is an optical photograph of an aluminum z-pinch target tube installed in the Z machine. Click on the thumbnail for a high-resolution image.

A pinch contracts plasma so suddenly and tightly that hydrogen isotopes available from sea water, placed in a capsule within the plasma, should fuse.

That’s the intent. Instead, the instability rapidly crimps the cylindrically contracting plasma until it resembles a string of sausages, or shreds the plasma into more fantastic, equally useless shapes. This damaged contraction loses the perfect symmetry of forces necessary to fuse the material.

Fast pinches at Z, which take place in less than 100 nanoseconds, already have produced some neutrons, a proof of fusion. But a major reason not enough neutrons have been produced to provide a source of peacetime electrical power is the MRT instability.

Sinars led seven experimental shots to map the disturbance. The experiments were motivated by a concept proposed last year by Sandia researcher Steve Slutz.

Traditionally, scientists would use an array of spidery wires to create a compressed, X-ray-generating ion cloud. The X-rays were then used to compress fusion fuel.

Slutz suggested that the magnetic pinching forces could be used to directly fuse fuel by compressing a solid aluminum liner around fusion material preheated by a laser.

Because the new concept would not produce X-rays as a heating tool but instead relied on directly compressing the fuel with magnetic pressure, the MRT instability was the primary threat to the concept.

“Once we started looking at solid liners it was easy to conceive of doing a controlled experiment to study the growth of the instability,” Sinars said.

This is because experimenters could etch the solid tubes, creating instabilities to whatever degree they desired. Accurate etching is not an option with fragile wire arrays.


X-rayThe top image is an X-ray (6.151 keV) photograph of the same target (see photo above) compressed by electromagnetic forces. The sequence of images below is cropped to show both outside edges of a cylinder from a camera’s point of view as they distort over time in the grip of the MRT instability. Some of the jet-like features are approximately 50 microns, smaller in diameter than a human hair. Click on the thumbnail for a high-resolution image.

The MRT problem occurs because even minute dips in a current-carrying surface — imperfections merely 10 nanometers in amplitude — can grow exponentially in amplitude to millimeter scales. In the experiments by Sinars and others, the tubes were scored with a sinusoidal perturbation to intentionally start this process.

“The series of pictures over a time scale of 100 nanoseconds brought the life of the MRT into focus,” Sinars said.

Previously, competing computer simulation programs had given conflicting predictions as to the extent of the threat posed by the MRT instability, leaving researchers in the position, says Sinars, of “a man with two watches: he never really knows what time it is.”

The more accurate simulations will enable researchers to better tweak the conditions of future Z firings, more effectively combating the effect of the instability.

Researchers believe that with thick liners and control of the MRT, the Z machine could achieve an output of 100 kilojoules to match the 100 kilojoules input to the fuel to start the fusion reaction. “That would be scientific breakeven,” Sinars said. “No one has achieved that.”

That day, he says, may be just two to three years away.

The work is reported in a paper in the Oct. 29 issue of Physical Review Letters and is the subject of an invited talk on Nov. 11 by Sinars at the American Physical Society Plasma Physics meeting in Chicago. The work was paid for by Sandia’s Laboratory Directed Research and Development program and the U.S. Department of Energy.



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