The key issues are discussed in detail and, there is even a list of important things to watch out for. Trying to make decisions with only half the information can end up being quite costly. I hope you will find this article as helpful to you as it was for me.

World Can Be Powered by Alternative Energy, Using Today’s Technology, in 20-40 Years, Experts Say

If someone told you there was a way you could save 2.5 million to 3 million lives a year and simultaneously halt global warming, reduce air and water pollution and develop secure, reliable energy sources — nearly all with existing technology and at costs comparable with what we spend on energy today — why wouldn’t you do it?

According to a new study coauthored by Stanford researcher Mark Z. Jacobson, we could accomplish all that by converting the world to clean, renewable energy sources and forgoing fossil fuels.

“Based on our findings, there are no technological or economic barriers to converting the entire world to clean, renewable energy sources,” said Jacobson, a professor of civil and environmental engineering. “It is a question of whether we have the societal and political will.”

He and Mark Delucchi, of the University of California-Davis, have written a two-part paper in Energy Policy in which they assess the costs, technology and material requirements of converting the planet, using a plan they developed.

The world they envision would run largely on electricity. Their plan calls for using wind, water and solar energy to generate power, with wind and solar power contributing 90 percent of the needed energy.

Geothermal and hydroelectric sources would each contribute about 4 percent in their plan (70 percent of the hydroelectric is already in place), with the remaining 2 percent from wave and tidal power.

Vehicles, ships and trains would be powered by electricity and hydrogen fuel cells. Aircraft would run on liquid hydrogen. Homes would be cooled and warmed with electric heaters — no more natural gas or coal — and water would be preheated by the sun.

Commercial processes would be powered by electricity and hydrogen. In all cases, the hydrogen would be produced from electricity. Thus, wind, water and sun would power the world.

The researchers approached the conversion with the goal that by 2030, all new energy generation would come from wind, water and solar, and by 2050, all pre-existing energy production would be converted as well.

“We wanted to quantify what is necessary in order to replace all the current energy infrastructure — for all purposes — with a really clean and sustainable energy infrastructure within 20 to 40 years,” said Jacobson.

One of the benefits of the plan is that it results in a 30 percent reduction in world energy demand since it involves converting combustion processes to electrical or hydrogen fuel cell processes. Electricity is much more efficient than combustion.

That reduction in the amount of power needed, along with the millions of lives saved by the reduction in air pollution from elimination of fossil fuels, would help keep the costs of the conversion down.

“When you actually account for all the costs to society — including medical costs — of the current fuel structure, the costs of our plan are relatively similar to what we have today,” Jacobson said.

One of the biggest hurdles with wind and solar energy is that both can be highly variable, which has raised doubts about whether either source is reliable enough to provide “base load” energy, the minimum amount of energy that must be available to customers at any given hour of the day.

Jacobson said that the variability can be overcome.

“The most important thing is to combine renewable energy sources into a bundle,” he said. “If you combine them as one commodity and use hydroelectric to fill in gaps, it is a lot easier to match demand.”

Wind and solar are complementary, Jacobson said, as wind often peaks at night and sunlight peaks during the day. Using hydroelectric power to fill in the gaps, as it does in our current infrastructure, allows demand to be precisely met by supply in most cases. Other renewable sources such as geothermal and tidal power can also be used to supplement the power from wind and solar sources.

“One of the most promising methods of insuring that supply matches demand is using long-distance transmission to connect widely dispersed sites,” said Delucchi. Even if conditions are poor for wind or solar energy generation in one area on a given day, a few hundred miles away the winds could be blowing steadily and the sun shining.

“With a system that is 100 percent wind, water and solar, you can’t use normal methods for matching supply and demand. You have to have what people call a supergrid, with long-distance transmission and really good management,” he said.

Another method of meeting demand could entail building a bigger renewable-energy infrastructure to match peak hourly demand and use the off-hours excess electricity to produce hydrogen for the industrial and transportation sectors.

Using pricing to control peak demands, a tool that is used today, would also help.

Jacobson and Delucchi assessed whether their plan might run into problems with the amounts of material needed to build all the turbines, solar collectors and other devices.

They found that even materials such as platinum and the rare earth metals, the most obvious potential supply bottlenecks, are available in sufficient amounts. And recycling could effectively extend the supply.

“For solar cells there are different materials, but there are so many choices that if one becomes short, you can switch,” Jacobson said. “Major materials for wind energy are concrete and steel and there is no shortage of those.”

Jacobson and Delucchi calculated the number of wind turbines needed to implement their plan, as well as the number of solar plants, rooftop photovoltaic cells, geothermal, hydroelectric, tidal and wave-energy installations.

They found that to power 100 percent of the world for all purposes from wind, water and solar resources, the footprint needed is about 0.4 percent of the world’s land (mostly solar footprint) and the spacing between installations is another 0.6 percent of the world’s land (mostly wind-turbine spacing), Jacobson said.

One of the criticisms of wind power is that wind farms require large amounts of land, due to the spacing required between the windmills to prevent interference of turbulence from one turbine on another.

“Most of the land between wind turbines is available for other uses, such as pasture or farming,” Jacobson said. “The actual footprint required by wind turbines to power half the world’s energy is less than the area of Manhattan.” If half the wind farms were located offshore, a single Manhattan would suffice.

Jacobson said that about 1 percent of the wind turbines required are already in place, and a lesser percentage for solar power.

“This really involves a large scale transformation,” he said. “It would require an effort comparable to the Apollo moon project or constructing the interstate highway system.”

“But it is possible, without even having to go to new technologies,” Jacobson said. “We really need to just decide collectively that this is the direction we want to head as a society.”

Jacobson is the director of Stanford’s Atmosphere/Energy Program and a senior fellow at Stanford’s Woods Institute for the Environment and the Precourt Institute for Energy.

Stanford University (2011, January 27). World can be powered by alternative energy, using today’s technology, in 20-40 years, experts say. ScienceDaily. Retrieved January 27, 2011, from http://www.sciencedaily.com­ /releases/2011/01/110126091443.htm

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The Original Post is Located Here: World Can Be Powered by Alternative Energy

Whatever the reality, rising long term global demands seem certain to outstrip production in the next decade, especially given the high and rising costs of developing new super-fields such as Kazakhstan’s offshore Kashagan and Brazil’s southern Atlantic Jupiter and Carioca fields, which will require billions in investments before their first barrels of oil are produced.

In such a scenario, additives and substitutes such as biofuels will play an ever-increasing role by stretching beleaguered production quotas. As market forces and rising prices drive this technology to the forefront, one of the richest potential production areas has been totally overlooked by investors up to now Central Asia. Formerly the USSR’s cotton “plantation, the region is poised to become a major player in the production of biofuels if sufficient foreign investment can be procured. Unlike Brazil, where biofuel is manufactured largely from sugarcane, or the United States, where it is primarily distilled from corn, Central Asia’s ace resource is an indigenous plant, Camelina sativa.

Of the former Soviet Caucasian and Central Asian republics, those clustered around the shores of the Caspian, Azerbaijan and Kazakhstan have seen their economies boom because of record-high energy prices, while Turkmenistan is waiting in the wings as a rising producer of natural gas.

Farther to the east, in Uzbekistan, Kyrgyzstan and Tajikistan, geographical isolation and relatively scant hydrocarbon resources relative to their Western Caspian neighbors have largely inhibited their ability to cash in on rising global energy demands up to now. Mountainous Kyrgyzstan and Tajikistan remain largely dependent for their electrical needs on their Soviet-era hydroelectric infrastructure, but their heightened need to generate winter electricity has led to autumnal and winter water discharges, in turn severely impacting the agriculture of their western downstream neighbors Uzbekistan, Kazakhstan and Turkmenistan.

What these three downstream countries do have however is a Soviet-era legacy of agricultural production, which in Uzbekistan’s and Turkmenistan case was largely directed towards cotton production, while Kazakhstan, beginning in the 1950s with Khrushchev’s “Virgin Lands” programs, has become a major producer of wheat. Based on my discussions with Central Asian government officials, given the thirsty demands of cotton monoculture, foreign proposals to diversify agrarian production towards biofuel would have great appeal in Astana, Ashgabat and Tashkent and to a lesser extent Astana for those hardy investors willing to bet on the future, especially as a plant indigenous to the region has already proven itself in trials.

Known in the West as false flax, wild flax, linseed dodder, German sesame and Siberian oilseed, camelina is attracting increased scientific interest for its oleaginous qualities, with several European and American companies already investigating how to produce it in commercial quantities for biofuel. In January Japan Airlines undertook a historic test flight using camelina-based bio-jet fuel, becoming the first Asian carrier to experiment with flying on fuel derived from sustainable feedstocks during a one-hour demonstration flight from Tokyo’s Haneda Airport. The test was the culmination of a 12-month evaluation of camelina’s operational performance capability and potential commercial viability.

As an alternative energy source, camelina has much to recommend it. It has a high oil content low in saturated fat. In contrast to Central Asia’s thirsty “king cotton,” camelina is drought-resistant and immune to spring freezing, requires less fertilizer and herbicides, and can be used as a rotation crop with wheat, which would make it of particular interest in Kazakhstan, now Central Asia’s major wheat exporter. Another bonus of camelina is its tolerance of poorer, less fertile conditions. An acre sown with camelina can produce up to 100 gallons of oil and when planted in rotation with wheat, camelina can increase wheat production by 15 percent. A ton (1000 kg) of camelina will contain 350 kg of oil, of which pressing can extract 250 kg. Nothing in camelina production is wasted as after processing, the plant’s debris can be used for livestock silage. Camelina silage has a particularly attractive concentration of omega-3 fatty acids that make it a particularly fine livestock feed candidate that is just now gaining recognition in the U.S. and Canada. Camelina is fast growing, produces its own natural herbicide (allelopathy) and competes well against weeds when an even crop is established. According to Britain’s Bangor University’s Centre for Alternative Land Use, “Camelina could be an ideal low-input crop suitable for bio-diesel production, due to its lower requirements for nitrogen fertilizer than oilseed rape.

Camelina, a branch of the mustard family, is indigenous to both Europe and Central Asia and hardly a new crop on the scene: archaeological evidence indicates it has been cultivated in Europe for at least three millennia to produce both vegetable oil and animal fodder.

Field trials of production in Montana, currently the center of U.S. camelina research, showed a wide range of results of 330-1,700 lbs of seed per acre, with oil content varying between 29 and 40%. Optimal seeding rates have been determined to be in the 6-8 lb per acre range, as the seeds’ small size of 400,000 seeds per lb can create problems in germination to achieve an optimal plant density of around 9 plants per sq. ft.

Camelina’s potential could allow Uzbekistan to begin breaking out of its most dolorous legacy, the imposition of a cotton monoculture that has warped the country’s attempts at agrarian reform since achieving independence in 1991. Beginning in the late 19th century, the Russian government determined that Central Asia would become its cotton plantation to feed Moscow’s growing textile industry. The process was accelerated under the Soviets. While Azerbaijan, Kazakhstan, Tajikistan and Turkmenistan were also ordered by Moscow to sow cotton, Uzbekistan in particular was singled out to produce “white gold.”

By the end of the 1930s the Soviet Union had become self-sufficient in cotton; five decades later it had become a major exporter of cotton, producing more than one-fifth of the world’s production, concentrated in Uzbekistan, which produced 70 percent of the Soviet Union’s output.

Try as it might to diversify, in the absence of alternatives Tashkent remains wedded to cotton, producing about 3.6 million tons annually, which brings in more than $1 billion while constituting approximately 60 percent of the country’s hard currency income.

Beginning in the mid-1960s the Soviet government’s directives for Central Asian cotton production largely bankrupted the region’s scarcest resource, water. Cotton uses about 3.5 acre feet of water per acre of plants, leading Soviet planners to divert ever-increasing volumes of water from the region’s two primary rivers, the Amu Darya and Syr Darya, into inefficient irrigation canals, resulting in the dramatic shrinkage of the rivers’ final destination, the Aral Sea. The Aral, once the world’s fourth-largest inland sea with an area of 26,000 square miles, has shrunk to one-quarter its original size in one of the 20th century’s worst ecological disasters.

And now, the dollars and cents. Dr. Bill Schillinger at Washington State University recently described camelina’s business model to Capital Press as: “At 1,400 pounds per acre at 16 cents a pound, camelina would bring in $224 per acre; 28-bushel white wheat at $8.23 per bushel would garner $230.

Central Asia has the land, the farms, the irrigation infrastructure and a modest wage scale in comparison to America or Europe all that’s missing is the foreign investment. U.S. investors have the cash and access to the expertise of America’s land grant universities. What is certain is that biofuel’s market share will grow over time; less certain is who will reap the benefits of establishing it as a viable concern in Central Asia.

If the recent past is anything to go by it is unlikely to be American and European investors, fixated as they are on Caspian oil and gas.

But while the Japanese flight experiments indicate Asian interest, American investors have the academic expertise, if they are willing to follow the Silk Road into developing a new market. Certainly anything that lessens water usage and pesticides, diversifies crop production and improves the lot of their agrarian population will receive most careful consideration from Central Asia’s governments, and farming and vegetable oil processing plants are not only much cheaper than pipelines, they can be built more quickly.

And jatropha’s biofuel potential? Another story for another time.

The Original Post is Located Here: Central Asia’s Vast Biofuel Opportunity

Wave energy is produced when electricity generators are placed on the surface of the ocean. The energy provided is most often used in desalination plants, power plants and water pumps. Energy output is determined by wave height, wave speed, wavelength, and water density. To date there are only a handful of experimental wave generator plants in operation around the world.

The Aguadora Wave Park (AWP) in Portugal is the worlds first commercial wave farm. The AWP produces roughly 2.25 Mega-Watts of power (enough for 1500 homes) and cost just over 8.5 million euros to deploy (though by 2009 costs are expected to exceed 70 million euros).

Construction and Maintenance

Most turbines require a constant, powerful flow which works in opposition to the very nature of waves, as waves are inconsistent in both direction and power. Powerful storms and the corrosive power of salt water are also adversarial to the construction of a reliable energy collection device. Accounting for the aforementioned problems, a device and its maintenance may become too expensive to be a reliable alternative to coal, oil, biodiesel or even solar power.

Harnessing the Waves

Wave energy collection is, however, remarkably passive. Unlike oil which requires a distillation process before energy can be used, wave energy is automatically converted by turbines. Wave energy is also environmentally friendly, as it creates no atmospheric pollution and has a small carbon footprint (non-existent if not for the manufacture of its devices). More-so, it allows us to utilize a space which has, for most of history, been underutilized: the ocean.

The flowing waters in the rivers and tidal waves can be a good source of alternative energy. With 70% of the earth’s surface covered with water, a great amount of energy can be produced by placing turbines at strategic locations under strong currents. This method of generating electric power is called hydrokinetic power generation.

The Future of Wave Power

According to Trey Taylor Co founder & president of Verdant Power, 4 commercial projects are planned for the next 3-5 years which should have the capacity to produce more than 200 MW when operating in waterways. As great minds continue to tackle the problems of renewable energy, we may see major advancements making wave energy more feasible. Groups such as OREC (Ocean Renewable Energy Coalition), continue to drum up support for projects, but it seems policy makers are a bit uncertain of wave energy’s true benefits.

For now we should focus on implementing wind power and solar power strategies to replace our dependence on oil. It may seem like a panacea on paper, but the reality exposes the truth, wave power is just not ready for wide-scale commercial use yet.

The Original Post is Located Here: The Potential of Wave Power

For billions of years the sun has been spewing out gargantuan amounts of energy and if we can use even a miniscule portion of it, pollution-free and inexpensive power can be provided to every single home and industry for as long as we live. Consequently, many energy companies and scientists are strenuously working towards a model that can produce cheap energy in the least intrusive manner. Solé tiles are definitely a step in that direction.

A concept illustration showing the Solé idea compared to traditional panels

They look just as normal rooftop tiles and they can be fitted with least fuss and you don’t even feel the difference in terms of how your roof looks. Their light-weight performance polymer construction results in easy handling and construction. By using 20%-25% of the roof area the tiles can generate 860 kilowatt hours per square (or per 100 square feet) annually in an area with “5.8 peak sun hours” per day.

The Solé tiles came into existence when SRS Energy hired Bresslergroup as the designers of the first curved building-integrated photovoltaic (BIPV) roofing product. Bresslergroup is a Philedelphia-based product design company that has collaborated with clients like Black and Decker, Motorola, Becton Dickinson and Honeywell.

A prototype installation in Pennsylvania. The other tiles will be dyed to match

Peter Bressler, the principal of Bresslergroup, has been enamored with the idea of producing solar panels that can become an integral part of the roofing system. So he came up with the idea of condensing a massive solar panel into a modular system that can easily be used as a design element, rather than some extra contrivance about to destroy the look of the establishment.

So when SRS Energy hired Bresslergroup, instead of the typical, uninspiring silicon crystalline wafers, they created a polymeric material that allowed them to make the curve of the tile, and this produced the shape of the regular tile. For the panels they used extremely flexible triple-junction non-crystalline amorphous silicon cells made by Michigan-based UNI-SOLAR, known as a “thin film” technology.

The Solé tiles can be seamlessly integrated with the terra-cotta tiles on your roof. It’s like, the solar panel themselves become your roof, instead of you installing them on your roof. SRS Energy hopes that Solé tiles will become part of the architecture and building of residences and commercial properties.

Source: alternative-energy-news.info

The Original Post is Located Here: Solar Power Tiles for your Rooftop

The design for trapping sunlight using two elliptical mirrors, with M1 collecting sunlight and M2 (the zozzaroid) focusing sunlight back to the vertex of M1 and into the blackbody. (Right) The mirrors used in a scheme for steam generation. Image credit: De Luca and Fedullo.

In the Greek legend of Dionysius’ ear, Dionysius made a cave shaped like an ellipse in order to hear the words whispered by a prisoner in one of the foci of the cave. Some science museums today feature a similar exhibit, where two people at opposite ends of a room can whisper into giant ellipses and distinctly hear each others’ words. This sort of cave, called Dionysius’ ear, has also inspired the design of a new sunlight trap proposed by physicists Roberto De Luca and Aniello Fedullo, both of the University of Salerno in Italy.

As the scientists explain in a study to be published in the European Journal of Physics, their sunlight trapping system is the optical equivalent of acoustical Dionysius’ ear. The design consists of two parabolic mirrors arranged face-to-face. Sunlight first hits the larger mirror and reflects to the smaller mirror placed a short distance away. Then the light from the smaller mirror reflects back, this time being focused into the vertex of the larger mirror. By confining sunlight into this small region, scientists can ideally trap solar radiation. The sunlight is stored in a blackbody, which consists of a cavity with perfectly reflecting inner walls.

“Through a sunlight trap system, solar radiation is first concentrated in a small region of space and then sent into a blackbody, where it can be stored (not for an arbitrary long time, though) for a variety of uses,” De Luca told PhysOrg.com. “For example, after having trapped sunlight in a cavity with perfectly reflecting inner walls, what we call a blackbody, one can think of heating water enclosed in a container placed inside the cavity itself. Other uses of this concept are also conceivable.”

In their study, De Luca and Fedullo investigated the feasibility of such a perfect sunlight trapping system, which was first envisioned by Paolantonio Zozzaro, a high school physics professor from the Province of Salerno. Zozzaro, who is involved in alternative energy research, wondered what the shape of the smaller mirror should be in order to reflect all incident light rays to the vertex of the larger mirror. Through their calculations, De Luca and Fedullo found that the smaller mirror should have a specific elliptic or hyperbolic profile, similar to Dionysius’ ear. They call this secondary mirror a “zozzaroid.” They’ve shown that, theoretically, the design focuses sunlight very effectively, so that it can be transferred to a blackbody with a rather small hole.

The scientists hope that the new sunlight collector could be useful for a variety of alternative energy applications. In a follow-up study, De Luca has investigated the possibility of using the device to generate steam without the need for a convection fluid. In the hollow cavity of the blackbody, he added a metal container into which water is pumped. Through conduction, heat is transferred from the metal container to the water, which is transformed into superheated steam. The steam can then be used for applications such as power generation. In addition to steam generation, such a system might be able to transform sea water into drinking water using only solar energy.

“Let us consider the problem of drinking water on the coasts of hot regions of the globe,” De Luca said. “In these places, salt water and sunlight are available in great quantity. Well! It is now not difficult to show that one can use a sunlight trap to heat one side of a metal surface dividing a cylindrical blackbody in two parts. On the other side of the metal surface (which attains a temperature very close to that of the opposite side), one can spray sea water. The generated vapor will then rise in the second chamber of the blackbody and salt will drop down due to gravity. By condensation of the generated vapor, one finally obtains drinkable water.”

De Luca and Fedullo predict that constructing a prototype of this system will involve technical challenges due to the highly idealized scheme. However, they hope that a close approximation to the ideal system could lead to many exciting possibilities.

“There can be more applications indeed,” De Luca said. “If one can generate overheated steam, one is able to produce electricity, as one does in ordinary thermoelectric power plants. In our case, however, one does not need to burn fossil fuel to generate heat. On the other hand, owing to the periodic availability of sunlight, one has to experiment with new types of controlled power generation systems. This new type of technology may be implemented, on a rather large scale, in a region of the world where the local social and economical development is not yet strictly linked to the availability of fossil fuel and where solar radiation is a rather ample resource.

“A group of developed countries can then make an agreement with the country having such characteristics: We shall invest in testing a model of sustainable industrial development based on alternative energies in your [undeveloped] country, using our technologies and our funds. In return, you will inherit the new developed technology (comprising the possibility of having a public transportation system based on hydrogen vehicles) in the near future, solve some occupational problems and, probably, have a better production of drinking water. Most of all, your country will not contribute to the greenhouse effect, being the first example of a fully developed region whose industrial production and human activity do not emit carbon dioxide into the atmosphere.”

Source: PhysOrg.com . More information: R De Luca and A Fedullo. “Focusing light rays back to the vertex of a reflecting parabolic collector: the equivalent of Dionysius ear effect in optical systems.” European Journal of Physics. (to be published).

The Original Post is Located Here: Sunlight Trap Could Lead to New Generation of Solar Devices

Cell phones, computers, MP3 players, kitchen stoves, and irons all have one thing in common: They need electricity. And in the future, more and more cars will also be fuelled by electric power. If the latest forecast from the World Energy Council WEC can be believed, global electricity requirements will double in the next 40 years. At the same time, prices for the dwindling resources of petroleum and natural gas are climbing.

“Rising energy prices are making alternative energy sources increasingly cost-effective. Sometime in the coming years, renewable energy sources, such as solar energy, will be competitive, even without subsidization,” explains Dr. Arnold Gillner, head of the microtechnology department at the Fraunhofer Institute for Laser Technology in Aachen, Germany. “Experts predict that grid parity will be achieved in a few years. This means that the costs and opportunities in the grid will be equal for solar electricity and conventionally generated household electricity.” Together with his team at the Fraunhofer Institute for Laser Technology ILT in Aachen, this researcher is developing technologies now that will allow faster, better, and cheaper production of solar cells in the future. “Lasers work quickly, precisely, and without contact. In other words, they are an ideal tool for manufacturing fragile solar cells. In fact, lasers are already being used in production today, but there is still considerable room for process optimization.” In addition to gradually improving the manufacturing technology, the physicists and engineers in Aachen are working with solar cell developers – for example, at the Fraunhofer Institute for Solar Energy Systems ISE in Freiburg – on new engineering and design alternatives.

New production technologies allow new design alternatives
At “Laser 2009” in Munich, the researchers will be demonstrating how lasers can drill holes into silicon cells at breathtaking speed: The ILT laser system drills more than 3,000 holes within one second. Because it is not possible to move the laser source at this speed, the experts have developed optimized manufacturing systems which guide and focuses the light beam at the required points. “We are currently experimenting with various laser sources and optical systems,” Gillner explains. “Our goal is to increase the performance to 10,000 holes a second. This is the speed that must be reached in order to drill 10,000 to 20,000 holes into a wafer within the cycle time of the production machines.”

The tiny holes in the wafer – their diameter is only 50 micrometers – open up undreamt-of possibilities for the solar cell developers. “Previously, the electrical contacts were arranged on the top of the cells. The holes make it possible to move the contacts to the back, with the advantage that the electrodes, which currently act as a dark grid to absorb light, disappear. And so the energy yield increases. The goal is a degree of efficiency of 20 percent% in industrially-produced emitter wrap-through (EWT) cells, with a yield of one-third more than classic silicon cells,” Gillner explains. The design principle itself remains unchanged: In the semi-conductor layer, light particles, or photons, produce negative electrons and positive holes, each of which then wanders to the oppositely poled electrodes. The contacts for anodes and cathodes in the EWT cells are all on the back, there is no shading caused by the electrodes, and the degree of efficiency increases. With this technique, it may one day be possible to use unpurified “dirty” silicon to manufacture solar cells that have poorer electrical properties, but that are cheaper.

Drilling holes into silicon cells is only one of many laser applications in solar cell manufacturing. In the EU project Solasys – Next Generation Solar Cell and Module Laser Processing Systems – an international research team is currently developing new technologies that will allow production to be optimized in the future. ILT in Aachen is coordinating the six million euro project. “We are working on new methods that make the doping of semiconductors, the drilling and the surface structuring of silicon, the edge isolation of the cells, and the soldering of the modules more economical,” project coordinator Gillner explains. For example, “selective laser soldering” makes it possible to improve the rejection rates and quality of the contacting, and so reduce manufacturing costs. Until now, the electrodes were mechanically pressed onto the cells, and then heated in an oven. “But silicon cells often break during this process,” Gillner knows. “Breakage is a primary cost factor in production.” On the other hand, however, with “selective laser soldering” the contacts are pressed on to the cells with compressed air and then soldered with the laser. The mechanical stress approaches zero and the temperature can be precisely regulated. The result: Optimal contacts and almost no rejects.

Laser technology means more efficient thin film cells
Laser technology is also helping to optimize the manufacture of thin film solar cells. The extremely thin film packages made of semiconducting oxide, amorphous silicon, and metal that are deposited onto the glass panels still have a market share of only ten percent. But as Gillner knows, “This could be higher, because thin film solar cells can be used anywhere that non-transparent glass panels can be mounted, for example, on house facades or sound-insulating walls. But the degrees of efficiency are comparable low at five to eight percent, and the production costs are comparatively high.” The laser researchers are working to improve these costs. Until now, the manufacturers have used mechanical methods or solid-state lasers in the nanosecond range in order to structure the active layers on the glass panels. In order to produce electric connections between the semiconductor and the metal, grooves only a few micrometers wide must be created. At the Fraunhofer-Gesellschaft booth at “Laser 2009” the ILT researchers will be demonstrating a 400-watt ultrashort pulse laser that processes thin-film solar modules ten times faster than conventional diode-pumped solid-state lasers. “The ultrashort pulse laser is an ideal tool for ablating thin layers: It works very precisely, does not heat the material and, working with a pulse frequency of 80 MHz, can process a 2-by-3 meter glass panel in under two minutes,” Gillner reports. “The technology is still very new, and high-performance scanning systems and optical systems adapted to the process must be developed first. In the medium term, however, this technology will be able to reduce production costs.”

The rise of laser technology in solar technology is just taking off, and it still has a long way to go. “Lasers simplify and optimize the manufacture of classic silicon and thin-film cells, and they allow the development of new design alternatives,” Gillner continues. “And so laser technology is making an important contribution towards allowing renewable energy sources to penetrate further into the energy market.”

Fraunhofer-Gesellschaft. “Lasers Are Making Solar Cells Competitive” ScienceDaily

The Original Post is Located Here: Lasers Are Making Solar Cells Competitive

The Original Post is Located Here: Front Page

RIWEA Turbine Inspection Robot

Now scientists at the Fraunhofer Institute for Factory Operation and Automation (IFF) in Germany have said they are developing a generation of robots which will be capable enough to monitor and maintain wind turbine generators on a round-the-clock basis. Their latest creation is RIWEA. It is a robot that inspects the rotor blades of wind energy converters.

It seems that wind energy converters bear the onslaught of weather all the time and in the process wear and tear of rotor blades is the normal phenomenon. So spotting out the damaged part in wind energy devices is quite challenging for humans. Often they have to perform this task at many feet above the ground where rotors are located. Rotor blades are made up of glass-fiber resistant plastics. Rotor blades have to endure wind, inertial forces, erosion, and other forces. Till now human beings have been shouldering the responsibility of inspecting wind energy converters at regular intervals. It turns out to be a time-consuming process that involves the technicians closely examining large surfaces. A rotor blade can be of 60 meters in length situated at windy heights. Now researchers are taking the help of Robot Ranchers to inspect windmills. They can perform the job more precisely than humans. Robot Ranchers can identify the minutest damage — even below the surface.

Dr. Norbert Elkmann, a project manager at the Fraunhofer IFF, says, “Our robot is not just a good climber. It is equipped with a number of advanced sensor systems. This enables it to inspect rotor blades closely.” The researchers are trying to consign, “inspection by humans” to history books.

The inspection system by Robot Ranchers consists of three components. Robot’s infrared radiator conducts heat to the surface of the rotor blades. This robot also has a high resolution thermal camera. This thermal camera records the temperature patterns and this helps in determining the flaws in the material. These robot ranchers are also equipped with an ultrasonic system and high resolution camera that would help in spotting damages which is difficult for humans to detect with naked eye. The greatest advantage of Robot Ranchers is its precision. It finds out the hairline cracks or other probable problems with great accuracy. A specially developed carrier system ensures that the inspection robot is guided securely and precisely along the surface of a rotor blade.
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The Original Post is Located Here: Robots Could Maintain Future Wind Farms

Hillside Turbine Farm

Wind energy has a formidable place in the field of alternative energy but critics always worry about the preservation of bio-diversity and farm birds. It is always a priority for the wind energy producers to keep in mind the comforts of the human and bird population. When plans were announced that UK will built the tallest wind turbines in the country the Npower Renewables tried to tackle the issue of biodiversity to alley the fears of environmentalists. Though they propose a plan of placing 65 turbines on nearly 5,000 acres (2,000ha) of hillside near Llanbrynmair in Powys they are tackling the issue of ecosystem too. Each turbine would be 137m (449ft) high.

As part of the project Npower is funding a major habitat restoration project in the area. “Npower renewables is proud to be pioneering the first habitat restoration proposal of this size in Wales in conjunction with the wind farm, and believes the scheme presents significant benefits for both the local and global environment,” added Mr Hain, the project manager.

Mr. Jacob Hain, said the scheme had the potential to “greatly contribute to the growing need for renewable energy”, while at the same time securing the future of the bird population and preventing further “deterioration of the peat lands”.

The turbines at Carnedd Wen will have the capability to produce between 130 and 195 megawatts and, provide the electricity needs of between 63,000 and 94,500 homes annually. They are planning to redevelop a site in in Llandinam, Powys, for 42, 122m (400ft) machines in May.

The Original Post is Located Here: Plan for Biggest Wind Turbines in the UK