Converting sunlight to electricity might no longer mean large panels of photovoltaic cells atop flat surfaces like roofs.

Using zinc oxide nanostructures grown on optical fibers and coated with dye-sensitized solar cell materials, researchers at the Georgia Institute of Technology have developed a new type of three-dimensional photovoltaic system.  The approach could allow PV systems to be hidden from view and located away from traditional locations such as rooftops.

“Using this technology, we can make photovoltaic generators that are foldable, concealed and mobile,” said Zhong Lin Wang, a Regents professor in the Georgia Tech School of Materials Science and Engineering.  “Optical fiber could conduct sunlight into a building’s walls where the nanostructures would convert it to electricity.  This is truly a three dimensional solar cell.”

Details of the research were published in the early view of the journal Angewandte Chemie International on October 22.  The work was sponsored by the Defense Advanced Research Projects Agency (DARPA), the KAUST Global Research Partnership and the National Science Foundation (NSF).

Dye-sensitized solar cells use a photochemical system to generate electricity.  They are inexpensive to manufacture, flexible and mechanically robust, but their tradeoff for lower cost is conversion efficiency lower than that of silicon-based cells.  But using nanostructure arrays to increase the surface area available to convert light could help reduce the efficiency disadvantage, while giving architects and designers new options for incorporating PV into buildings, vehicles and even military equipment.

Fabrication of the new Georgia Tech PV system begins with optical fiber of the type used by the telecommunications industry to transport data. First, the researchers remove the cladding layer, then apply a conductive coating to the surface of the fiber before seeding the surface with zinc oxide.  Next, they use established solution-based techniques to grow aligned zinc oxide nanowires around the fiber much like the bristles of a bottle brush.  The nanowires are then coated with the dye-sensitized materials that convert light to electricity.

Sunlight entering the optical fiber passes into the nanowires, where it interacts with the dye molecules to produce electrical current. A liquid electrolyte between the nanowires collects the electrical charges.  The result is a hybrid nanowire/optical fiber system that can be up to six times as efficient as planar zinc oxide cells with the same surface area.

“In each reflection within the fiber, the light has the opportunity to interact with the nanostructures that are coated with the dye molecules,” Wang (left) explained.  “You have multiple light reflections within the fiber, and multiple reflections within the nanostructures.  These interactions increase the likelihood that the light will interact with the dye molecules, and that increases the efficiency.”

Wang and his research team have reached an efficiency of 3.3 percent and hope to reach 7 to 8 percent after surface modification.  While lower than silicon solar cells, this efficiency would be useful for practical energy harvesting.  If they can do that, the potentially lower cost of their approach could make it attractive for many applications.

By providing a larger area for gathering light, the technique would maximize the amount of energy produced from strong sunlight, as well as generate respectable power levels even in weak light.  The amount of light entering the optical fiber could be increased by using lenses to focus the incoming light, and the fiber-based solar cell has a very high saturation intensity, Wang said.

Wang believes this new structure will offer architects and product designers an alternative PV format for incorporating into other applications.

“This will really provide some new options for photovoltaic systems,” Wang said.  “We could eliminate the aesthetic issues of PV arrays on building. We can also envision PV systems for providing energy to parked vehicles, and for charging mobile military equipment where traditional arrays aren’t practical or you wouldn’t want to use them.”

Wang and his research team, which includes Benjamin Weintraub and Yaguang Wei, have produced generators on optical fiber up to 20 centimeters in length.  “The longer the better,” said Wang, “because longer the light can travel along the fiber, the more bounces it will make and more it will be absorbed.”

Traditional quartz optical fiber has been used so far, but Wang would like to use less expensive polymer fiber to reduce the cost.  He is also considering other improvements, such as a better method for collecting the charges and a titanium oxide surface coating that could further boost efficiency.

Though it could be used for large PV systems, Wang doesn’t expect his solar cells to replace silicon devices any time soon.  But he does believe they will broaden the potential applications for photovoltaic energy.

“This is a different way to gather power from the sun,” Wang said.  “To meet our energy needs, we need all the approaches we can get.”

John D. Toon is manager of the research news and publications office at Georgia Institute of Technology.

That’s because electricity is nonexistent in Gathungu’s hometown of Njoro, in northwest Kenya. Landlines and other forms of communication are not as efficient, so Gathungu and millions of others in emerging nations rely on mobile phones. Charging the phones can be a headache in towns and villages where electricity is scarce.

Gathungu’s troubles may soon be over, though.

Kenya’s biggest mobile phone company, Safaricom Ltd., launched the nation’s first solar-charged phone this month. The handset comes with a regular electrical charger and a solar panel that charges the phone using the sun’s rays, company CEO Michael Joseph told CNN by telephone.

Retailing at about $35, the phones were manufactured by Chinese telecommunications company ZTE Corp. Safaricom plans to make an initial supply of 100,000 phones available.

“People are excited about these phones,” Joseph said. “I expect to be sold out in a week.”

Eco-friendly phones have been touted by several companies at global trade shows, but most have not been launched yet.

Samsung unveiled a solar-powered phone at the Mobile World Congress in Barcelona, Spain, earlier this year and introduced its first sun-powered phone in India in mid-June. The company expects its Solar Guru model to perform well in India, another country where electrical supply can be erratic.

Unlike many technological innovations, the solar phone is making its big splash in developing nations, where the need is the greatest. After the Solar Guru is in circulation in India, Samsung said, it plans to launch similar phones in other Asian markets, Europe and Latin America.

For the time being, Kenyans are happy to serve as early adopters.

“The power crisis here has been going on for ages,” Joseph said, adding that the Safaricom phone’s solar panel is small and portable, unlike charging devices some Kenyans now use.

Only about 1.3 million of Kenya’s 37 million people are connected to the national electrical grid, said Migwi Theuri, a spokesman for Kenya Power and Lighting Co. The east African nation, which gets most of its energy from hydro-generation, has been undergoing power rationing after a three-year drought.

Despite the limited availability of power, Kenya has one of the most vibrant cell phone markets in Africa, analysts say. An estimated 17 million Kenyans use mobile phones.

Some charge phones on bicycle-run generators, Joseph said. Or like, Gathungu, they pay businesses in major cities to charge their phones, sometimes waiting an entire day.

“There’s an enormous need for a device like this,” Joseph said of the solar phone, which can charge during talk time, as long as there are rays.

“They will continue to charge on natural light, even on cloudy days,” he added.

Gathungu plans to buy one of the new environmentally friendly phones. For him, it’s a matter of money and convenience. He earns 4,000 Kenya shillings ($53 dollars) a month as a waiter. Charging his phone for 50 shillings (70 cents) a week adds up. The solar phone would pay for itself, Gathungu said.

Until he buys one, he’ll keep making the trek to the shopping center every Sunday afternoon after church. He wouldn’t go into further detail about his mobile phone woes, not wanting to waste his battery charge on the call.

A California company hopes to store solar power by focusing thousands of mirrors on millions of gallons of liquefied salt. An artist’s rendering of such a solar plant is shown here.

The holy grail of renewable energy is a solar power plant that continues producing electricity after the sun goes down.

A Santa Monica, Calif., company called SolarReserve has taken a step toward making that a reality, filing an application with California regulators to build a 150-megawatt solar farm that will store seven hours’ worth of the sun’s energy in the form of molten salt.

Heat from the salt can be released when it’s cloudy or at night to create steam that drives an electricity-generating turbine.

The Rice Solar Energy Project, to be built in the Sonoran Desert east of Palm Springs, will “generate steady and uninterrupted power during hours of peak electricity demand,” according to SolarReserve’s license application.

So-called dispatchable solar farms would in theory allow utilities to avoid spending billions of dollars building fossil fuel power plants that are fired up only a few times a year when electricity demand spikes, like on a hot day.

SolarReserve is literally run by rocket scientists, many of whom formerly worked at Rocketdyne, a subsidiary of the technology giant United Technologies. Rocketdyne developed the solar salt technology, which was proven viable at the 10-megawatt Solar Two demonstration project near Barstow, Calif., in the 1990s.

United Technologies has licensed the technology to SolarReserve and will guarantee its performance — a crucial advantage for the startup when it seeks financing from skittish bankers to build the Rice solar farm.

As many as 17,500 large mirrors — each one 24 feet by 28 feet — will be attached to 12-foot pedestals. The mirrors, called heliostats, will be arrayed in a circle around a 538-foot concrete tower.

Atop the tower will sit a 100-foot receiver filled with 4.4 million gallons of liquid salt. The heliostats will focus the sun on the receiver, heating the salt to 1,050 degrees Fahrenheit. The liquefied salt flows through a steam-generating system to drive the turbine and is returned to the receiver to be heated again.

SolarReserve isn’t the only developer planning to tap molten salt to store solar energy. Abengoa Solar, for instance, intends to use salt storage at its 280-megawatt Solana solar trough plant outside Phoenix.

That project, however, will heat tubes filled with synthetic oil to create steam and transfer some of the heat to salt-filled storage tanks. By using salt for both steam and storage, SolarReserve can generate higher-temperature steam, which will allow the Rice power plant to operate much more efficiently, according to Kevin Smith, SolarReserve’s chief executive.

“Consequently, our system can capture three times the energy for the same pound of salt,” Mr. Smith wrote in an e-mail message. “Plus they have additional ‘bolt on’ equipment, plus multiple heat transfer steps to go from oil to salt to oil and then to steam for electricity generation.”

SolarReserve’s plant will be built on private land — the site of a former World War II-era Army airfield — near the desert ghost town of Rice. The company will air-cool the power plant, avoiding controversies over water use that have dogged other solar projects.

But the height of the solar tower — 653 feet when a maintenance crane is attached to the top — could generate resistance from conservationists worried about the impact of the project on desert vistas. A proposed SolarReserve power plant in Nevada ran into resistance from Air Force officials concerned that the tower would interfere with radar at a nearby military base.

The company said it is negotiating with California utilities to buy the electricity generated from the Rice project and expects the solar farm to go online in October 2013, barring unforeseen delays.

Mendez developed a Quantitative Habitability Theory to assess the current state of terrestrial habitability and to establish a baseline for relevant comparisons with past or future climate scenarios and other planetary bodies including extrasolar planets.

“It is surprising that there is no agreement on a quantitative definition of habitability,” said Mendez, a biophysicist. “There are well-established measures of habitability in ecology since the 1970s, but only a few recent studies have proposed better alternatives for the astrobiology field, which is more oriented to microbial life. However, none of the existing alternatives from the fields of ecology to astrobiology has demonstrated a practical approach at planetary scales.”

His theory is based on two biophysical parameters: the habitability (H), as a relative measure of the potential for life of an environment, or habitat quality, and the habitation (M), as a relative measure of biodensity, or occupancy. Within the parameters are physiological and environmental variables which can be used to make predictions about the distribution, and abundance of potential food (both plant and microbial life), environment and weather.

The image above shows a comparison of the potential habitable space available on Earth, Mars, Europa, Titan, and Enceladus. The green spheres represent the global volume with the right physical environment for most terrestrial microorganisms. On Earth, the biosphere includes parts of the atmosphere, oceans, and subsurface. The potential global habitats of the other planetary bodies are deep below their surface.

Enceladus has the smallest volume but the highest habitat-planet size ratio followed by Europa. Surprisingly, Enceladus also has the highest mean habitability in the Solar System, even though it is farther from the sun, and Earth, making it harder to get to. Mendez said Mars and Europa would be the best compromise between potential for life and accessibility.

“Various planetary models were used to calculate and compare the habitability of Mars, Venus, Europa, Titan, and Enceladus,” Mendez said. “Interestingly, Enceladus resulted as the object with the highest subsurface habitability in the solar system, but too deep for direct exploration. Mars and Europa resulted as the best compromise between habitability and accessibility. In addition, it is also possible to evaluate the global habitability of any detected terrestrial-sized extrasolar planet in the future. Further studies will expand the habitability definition to include other environmental variables such as light, carbon dioxide, oxygen, and nutrients concentrations. This will help expand the models, especially at local scales, and thus improve its application in assessing habitable zones on Earth and beyond.”

Studies about the effects of climate change on life are interesting when applied to Earth itself. “The biophysical quantity Standard Primary Habitability (SPH) was defined as a base for comparison of the global surface habitability for primary producers,” Mendez said. “The SPH is always an upper limit for the habitability of a planet but other factors can contribute to lower its value. The current SPH of our planet is close to 0.7, but it has been up to 0.9 during various paleoclimates, such as during the late Cretaceous period when the dinosaurs went extinct. I’m now working on how the SPH could change under global warming.”

The search for habitable environments in the universe is one of the priorities of the NASA Astrobiology Institute and other international organizations. Mendez’s studies also focus on the search for life in the solar system, as well as extrasolar planets.

“This work is important because it provides a quantitative measure for comparing habitability,” said NASA planetary scientists Chris McKay. “It provides an objective way to compare different climate and planetary systems.”

“I was pleased to see Enceladus come out the winner,” McKay said. “I’ve thought for some time that it was the most interesting world for astrobiology in the solar system.”

Mendez presented his results at the Division for Planetary Sciences of the American Astronomical Society meeting earlier this month.

Source

Scientists at Princeton and Cambridge say that most of the universe is regularly destroyed.  It’s space-time-twisted into black holes, in fact, which is about as utterly destroyed as you can get without pissing off Zeus.  In each destruction cycle only a small seed of habitable space survives, which grows phoenix-like to provide a new universe due to the apparently all-powerful dark matter.

The model is based on M-Theory – an expanded limit of string theory with an extra dimension, making it only slightly less esoteric than studying the symbolism of Chopin’s work in a universe where the Nazis won the war.  I’m not saying that M-theory is poorly understood or developed, but they can’t even agree on what the ‘M’ actually stands for.  Seriously.

In this model, the universe is a region on a multidimensional membrane called a “brane”, and it’s only one of many.  When these branes collide huge regions of our brane get bunched into extremely uninhabitable black holes, with only a small region of space left for us.  Without dark energy to inflate these gaps, a few cycles of this would annihilate everything.

As with all string-theory siblings, it’s an extremely interesting idea with less proof than the “Hitler shot JFK” theory, and the reasons for including dark energy sound suspiciously like “because our math doesn’t work without it.”  Plus, since it deals in six hundred billion year timescales and the End of Almost Everything, it’s slightly less measurable than a unicorn horn diameter.

Source

Galactic cosmic rays are speeding charged particles that include protons and heavier atomic nuclei. They come from outside the solar system, though their exact sources are still being debated.

Earth dwellers are protected from cosmic rays by the planet’s magnetic field and atmosphere. But outside Earth’s protective influence, cosmic rays can play havoc with spacecraft electronics – they may be responsible for some recent computer glitches on NASA’s Kepler spacecraft, which temporarily halted its planet-hunting observations. They can also damage astronaut DNA, which can lead to cancer.

Now, the influx of galactic cosmic rays into our solar system has reached a record high. Measurements by NASA’s Advanced Composition Explorer (ACE) spacecraft indicate that cosmic rays are 19 per cent more abundant than any previous level seen since space flight began a half century ago.

Solar minimum

“The space era has so far experienced a time of relatively low cosmic ray activity,” says Richard Mewaldt of Caltech, who is a member of the ACE team. “We may now be returning to levels typical of past centuries.”

The sun’s magnetic field normally blocks some of the cosmic rays, preventing them from entering the solar system. But that protection has weakened of late. The solar wind, which helps project the sun’s magnetic field out into space, has dropped in pressure to a 50-year low. And the strength of the magnetic field in interplanetary space is down to just 4 nanoTesla, compared to the more typical 6 to 8 nanoTesla.

The recent weakening of the shield is due to cycles in solar activity. The sun is at a minimum in its 11-year cycle of magnetic activity, and this particular dip is deeper than any other seen in nearly a century.

Extra shielding

That may be a sign that the unusually active sun of the past 100 years or so is returning to the historical norm of lower activity, or even entering a so-called grand minimum of exceptionally low activity that could last centuries.

Scientists can infer variations in the sun’s magnetic activity over the past 10,000 years from the abundance of rare isotopes in Greenland ice cores.

If the increase in cosmic rays is here to stay, it could make long-duration human missions in space more challenging. Astronauts aboard the International Space Station are still close enough to enjoy protection from Earth’s magnetic field, but any sent in future to the moon or beyond will be outside that field.

“The increase is significant, and it could mean we need to re-think how much radiation shielding astronauts take with them on deep-space missions,” Mewaldt says.

Down time

If there’s a long-term increase, it might also make sense to design future robotic missions for extra robustness against radiation, says Roger Hunter of NASA’s Ames Research Center in Moffett Field, California, who manages NASA’s planet-hunting Kepler mission.

It is not clear whether Kepler’s temporary computer glitches were due to cosmic-ray hits, he says. But the spacecraft is designed to be able to recover from such events, going into a safe mode while mission controllers work to restore it to normal operation, he adds.

“Our only concern is will we see more events as a result of the cosmic-ray increase,” he says. Since its launch in March, Kepler has lost 3.5 days of observing time due to glitches that put it into safe mode. However, the mission team always planned for occasional days lost to glitches, and considers up to 12 lost days per year to be acceptable.

Gathungu’s troubles may soon be over, though.

Kenya’s biggest mobile phone company, Safaricom Ltd., launched the nation’s first solar-charged phone this month. The handset comes with a regular electrical charger and a solar panel that charges the phone using the sun’s rays, company CEO Michael Joseph told CNN by telephone.

Retailing at about $35, the phones were manufactured by Chinese telecommunications company ZTE Corp. Safaricom plans to make an initial supply of 100,000 phones available.

“People are excited about these phones,” Joseph said. “I expect to be sold out in a week.”

Eco-friendly phones have been touted by several companies at global trade shows, but most have not been launched yet.

Samsung unveiled a solar-powered phone at the Mobile World Congress in Barcelona, Spain, earlier this year and introduced its first sun-powered phone in India in mid-June. The company expects its Solar Guru model to perform well in India, another country where electrical supply can be erratic.

Unlike many technological innovations, the solar phone is making its big splash in developing nations, where the need is the greatest. After the Solar Guru is in circulation in India, Samsung said, it plans to launch similar phones in other Asian markets, Europe and Latin America.

For the time being, Kenyans are happy to serve as early adopters.

“The power crisis here has been going on for ages,” Joseph said, adding that the Safaricom phone’s solar panel is small and portable, unlike charging devices some Kenyans now use.

Only about 1.3 million of Kenya’s 37 million people are connected to the national electrical grid, said Migwi Theuri, a spokesman for Kenya Power and Lighting Co. The east African nation, which gets most of its energy from hydro-generation, has been undergoing power rationing after a three-year drought.

Despite the limited availability of power, Kenya has one of the most vibrant cell phone markets in Africa, analysts say. An estimated 17 million Kenyans use mobile phones.

Some charge phones on bicycle-run generators, Joseph said. Or like, Gathungu, they pay businesses in major cities to charge their phones, sometimes waiting an entire day.

“There’s an enormous need for a device like this,” Joseph said of the solar phone, which can charge during talk time, as long as there are rays.

“They will continue to charge on natural light, even on cloudy days,” he added.

Gathungu plans to buy one of the new environmentally friendly phones. For him, it’s a matter of money and convenience. He earns 4,000 Kenya shillings ($53 dollars) a month as a waiter. Charging his phone for 50 shillings (70 cents) a week adds up. The solar phone would pay for itself, Gathungu said.

Until he buys one, he’ll keep making the trek to the shopping center every Sunday afternoon after church. He wouldn’t go into further detail about his mobile phone woes, not wanting to waste his battery charge on the call.

source

The U.S. Army is about to start building a 500 megawatt solar thermal plant in the California desert. When it’s done, the facility will be one of the largest renewable energy plants in the world. Which is kind of ironic, since the Army doesn’t pay all that much attention to climate change. Turns out, sustainable energy is safer, said Dr. Kevin Geiss, the program director for the project.

The Army today introduced the private developers, Clark Enterprises and a Spanish company called Acciona, that will build this gargantuan solar plant at Ft. Irwin, California. It’s one of the military’s primary locations to train for war. Right now, like many military bases, most of its energy comes from diesel generators—with long, vulnerable lines back to the fuel source. Screw the green movement, solar just makes sense.

In a bloggers’ conference call today, Geiss explained:

One way to look at this is to just take a step back and not use the word renewable or alternative or anything and say okay, if we were going to try to get power and energy for our installations and we wanted to make sure that we have consistent access, that it’s affordable, that we would be at a low risk for disruption, that we would have decreased impact on the environment, I would say that our renewable and alternative energies would pop to the top of the list.

Ft. Irwin is prime location.  There are 14,000 acres of land on the base, most of it unused unoccupied. Sites like this mean that the Army can push renewable energy development, said Geiss. All over the country, the Army has huge patches of land next to bases with a constant energy demand.

And Ft. Irwin has some bonus features. It’s right next to high capacity transmission lines, which means that later, the army can sell most of the excess energy to southern California.  At peak, Ft. Irwin only needs 35 megawatts, leaving around 465 to shed.

But the Army also wants to distance Ft. Irwin from the grid if necessary, said Geiss. Developers will need to build a mechanism for the base to be completely energy autonomous in an emergency situation. That’s one of the major differences between Ft. Irwin and the Army’s active solar plant at Nellis Air Force Base in Nevada. Nellis produces around 14 megawatts and remains tethered to the grid.

The solar plant at Ft. Irwin will require at least 1.5 billion dollars total, and should be ready to crank electrons by 2022.

This will be a big break from the military past, said Geiss. “We have clear examples, at least in the past 100 years, where the lack of fuel has hindered military operations. What held Patton back in Germany was that Eisenhower was turning the fuel over to Montgomery.”

No longer. Like it or not, camo is the new green.

Infrasonic (aka Soundless Music) was a carefully controlled psychological experiment, in the form of two back-to-back concerts. These concerts were highly unusual because some of the music was laced with infrasound (i.e.extreme bass sound, below 20Hz in frequency).

Until recently, infrasound was thought to have no effect on humans, but when researchers in London played infrasound to a group of people, they started to get nervous, anxious and scared. This could be why people see ghosts – they’re in an old house, the house is moving slowly and making low vibrations (infrasound), the person starts to feel scared, so the brain creates ghosts out of shadows as a reason for the person being scared.

“Some scientists have suggested that this level of sound may be present at some allegedly haunted sites and so cause people to have odd sensations that they attribute to a ghost — our findings support these ideas,” said Professor Richard Wiseman, a psychologist at the University of Hertfordshire in southern England.

In the first controlled experiment of infrasound, Lord and Wiseman played four contemporary pieces of live music, including some laced with infrasound, at a London concert hall and asked the audience to describe their reactions to the music.
The audience did not know which pieces included infrasound but 22 percent reported more unusual experiences when it was present in the music.
Their unusual experiences included feeling uneasy or sorrowful, getting chills down the spine or nervous feelings of revulsion or fear.
“These results suggest that low frequency sound can cause people to have unusual experiences even though they cannot consciously detect infrasound,” said Wiseman, who presented his findings to the British Association science conference.

In 1998, Vic Tandy, experimental officer and part-time lecturer in the school of international studies and law at Coventry University, and Dr. Tony Lawrence of the psychology department wrote a paper called “Ghosts in the Machine” for the Journal of the Society for Psychical Research. They cited infrasound as the cause of apparitions seen by staff at a so-called haunted laboratory in Warwick.

Several years earlier, Tandy was working late in the “haunted” Warwick laboratory when he saw a gray thing coming for him. “I felt the hairs rise on the back of my neck,” he said. “It seemed to be between me and the door, so the only thing I could do was turn and face it.” But the thing disappeared. However, it reappeared in a different form the next day when Tandy was doing some work on his fencing foil. “The handle was clamped in a vice on a workbench, yet the blade started vibrating like mad,” he said. He wondered why the blade vibrated in one part of room but  not in another. The explanation, he discovered, was that infrasound was coming from an extractor fan. “When we finally switched it off, it was as if a huge weight was lifted,” he said. “It makes me think that one of the applications of this ongoing research could be a link between infrasound and sick-building syndrome.” When he measured the infrasound in the laboratory, the showing was 18.98 hertz–the exact frequency at which a human eyeball starts resonating. The sound waves made his eyeballs resonate and produced an optical illusion: He saw a figure that didn’t exist.

There are many phenomena that occur in the world around us that can be explained by science, there are many yet to be explained. Myths often arise surrounding these unexplained phenomena.

Lush valleys with good grazing land right beside a big lake – just the place to live… or is it? In 1986, 1700 people and thousands of animals living near Lake Nyos in the west-African country of Cameroon died overnight. People from neighbouring villages believed that an evil spirit woman lived in the lake, and she had killed everyone and everything because the people had angered her somehow. However, a bunch of researchers have discovered that the mass extinction in 1986 was due to a freak accident rather than supernatural murder.

Lake Nyos is in the top of an extinct volcano which is generating carbon dioxide. This gas works its way up through the rock beneath Lake Nyos, and ends up at the bottom of the lake. On that fatal night in 1986, some event (a mudslide, little earthquake, strong wind) disturbed the water and released the carbon dioxide – the lake burped. Because carbon dioxide is heavier than air, the cloud of gas settled down into the valleys, pushing away all the oxygen and suffocating all the people and animals.

To stop this kind of thing happening again, a team of scientists and engineers have come up with way of circulating the water, which gradually releases the carbon dioxide into the atmosphere without the devastating effects seen on that night in 1986.

An Australian phenomenon, Min Min lights, has recently been explained through the use of science. Professor Jack Pettigrew of the University of Queensland, says that the lights are actually an inverted mirage of light sources which are, in some cases, hundreds of kilometres away over the horizon. Pettigrew used a car traveling from beyond the horizon with the lights on high beam to create his own Min Min light. The light is able to travel from beyond the horizon due to a blanket of cold air down at ground level that can bend the light around the globe.

Infrasound is especially dangerous, due to its strong vibrations, or oscillations. Infrasound waves hug the ground, travel for long distances without losing strength, and are unstoppable. Not much amplitude is needed to produce negative effects in the human body, and even mild infrasound exposure requires several hours, or even days, to reverse symptoms.
Natural and man-made infrasound occurs in our world, but thankfully, extreme manifestations and contact with humans are infrequent.

In 2007, a Los Angeles firm called SolarReserve proposed the construction of a $700 million solar thermal power plant, covering two square miles near the Nevada Air Force base, where the sun shines brightly virtually all year long. There aren’t issues with wildlife, the company said. Moreover, it could hook up its solar-powered turbines to existing transmission lines left behind by a defunct mining operation.

But Col. Howard D. Belote, installation commander at Nellis, said this week that the plan won’t fly and is urging the government to turn it down.

The Air Force’s opposition demonstrates some of the conflicts and delays that could lie ahead as renewable-energy projects search for places to put big wind turbines or solar collectors, even in Western states where the federal government is a major landholder. SolarReserve has been negotiating with the Air Force for 18 months and has already revised its plans once to move the plant 25 miles away from the base, at the Air Force’s suggestion.

The Nevada plant was supposed to be a showcase for SolarReserve: one of the largest solar plants in the world, using heat-transfer technology developed for space rockets by United Technologies. A field of mirrors would focus sunlight on a receiver on a tall tower, where it would heat the molten salt to 1,050 degrees Fahrenheit, much hotter than other solar plants using similar technology. The molten salt would then flow to a storage tank, where its heat would generate steam and power conventional steam turbines similar to those in coal plants.

By using the molten-salt method, the plant could store 16 hours of power supply, easing concerns about the ability of solar plants to provide power when it is dark or cloudy. It would have a capacity of 100 megawatts, enough to power about 50,000 homes.

“We’re trying to build a facility that runs 24 hours a day,” said Kevin B. Smith, SolarReserve’s chief executive.

But Belote said the solar plant would compromise classified aspects of the Air Force’s training range and would interfere with radar. He said the Air Force would tell the Interior Department’s Bureau of Land Management, which owns most of the land in the state, to reject the proposal. (The bureau controls more than 20 million acres of land with wind energy potential and more than 30 million acres with solar potential.)

SolarReserve officials “did a lot of [research] with publicly available tools,” Belote said. “But when they came back for an official look the answer was, ‘Man, that’s still too close.’ And because of the sensitivity [of information], I can’t tell them why. . . . Unfortunately for them and us, there’s stuff on the Nevada testing range we don’t tell anyone about.” Belote suggested they try another site, either 100 miles to the southeast or about 80 miles to the northeast, near the town of Mesquite.

Top executives at SolarReserve said they were upset and disappointed. They feel that the Air Force pointed them toward the second site before rejecting it. Moreover, the Nellis base boasts of its own photovoltaic panels — the nation’ largest solar photovoltaic power plant; on May 27, Belote hosted President Obama and Senate Majority Leader Harry Reid (D-Nev.), who toured the solar facility.

Obama “got a nice tour of the facility, but I expect he had not been informed that Nellis was resisting renewable-energy facilities in the surrounding area,” Smith said. “The fact that Nellis AFB allowed someone to build a PV [photovoltaic] facility on the base and sell them the power is great, but they are hiding behind it while they try and stop other development in the region.”

The Air Force has a history of balking at buildings near the 2.9-million-acre flight-training range in Nevada, which makes up 41 percent of the Air Force’s total training acres worldwide. In the past, the service has objected to tall hotel projects in nearby Las Vegas and to wind turbines.

But SolarReserve’s chief executive Smith said “we tried to make sure we had a site the Air Force wouldn’t object to.” The company’s plan would place a lone solar-power tower below a 2,000-foot-tall mountain range that separates their location from the base. The base sits well above the height of the tower.

In addition, the project would create many construction jobs, Smith noted.

SolarReserve is still hoping it can prevail upon the Air Force to approve the site near Nellis and has appealed to members of Congress for help. Belote has arranged for classified briefings to explain his objections to select Senate staffers, and he has promoted the project to the mayor of Mesquite, a small town just on the Nevada side of the Arizona border, 87 miles northeast of Las Vegas.

“Our community is very, very interested in alternative energy and the thought of being green,” said Mesquite Mayor Susan M. Holecheck. “Historically, our economic base has been gaming and tourism.” Another solar company has already proposed a project using similar technology. Holecheck said the town would have to study whether a SolarReserve site would interfere with plans for moving the town’s airport. And the Bureau of Land Management would also need to agree to provide land.

Smith hasn’t had time to pursue the Mesquite idea. He said the Air Force just mentioned the alternative a month ago. “The difficulty with moving to a new site is you start over again,” he said. “It is certainly something we can do if we fail at the current site but it will delay the project 12 to 18 months.”