Energía Renovable | Renewable Energy

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Vestas launches design for world's largest offshore wind turbine

By Tannith Cattermole
22:31 April 6, 2011





Vestas has revealed plans to build the largest dedicated offshore wind turbine in the world - the 164 m diameter V164
Image Gallery (3 images)

Offshore wind power specialist Vestas has revealed plans to build the largest dedicated offshore wind turbine in the world. The proposed V164 would have a 7.0 MW capacity, twice that of its predecessor, the 3.0 MW V112. The awesome 164 meter (538 ft) diameter rotor would eclipse the size of the current titleholder, the prototype G10X installed by Gamesa in Spain in 2009 which has a diameter of 128 m (420 ft).
The world's largest capacity wind turbine, the Enercon E-126 has a rated capacity of 7.58 MW, but its 126 m (413 ft) diameter would still be dwarfed by the V164. The proposed Sway AS rotor diameter of 145m (476ft) and could stretch capacity to 10 MW.

Vestas V164-7.0MW has a blade length of 80 meters, the length of nine routemaster buses


Horizontal-axis wind turbines (HAWT) are designed with a rotor shaft and electrical generator at the top of a tower. Small turbines are pointed into the wind by a simple wind vane, while large turbines generally use a wind sensor coupled with a servo motor. Most have a gearbox, which turns the slow rotation of the blades into a quicker rotation that is more suitable to drive an electrical generator.
Vestas approached the design using two separate R&D teams – one investigating direct drive, and one investigating geared-train turbines – and eventually a proven medium-speed drive-train solution was chosen.
Vestas' V164 has been specially designed to withstand the punishing North Sea winds and the business case is aimed at the European market, especially the North European countries of UK, France, Sweden and Germany among others.
Construction of the first V164-7.0 MW prototypes are expected in late 2012, with serial production set to begin in early 2015 if enough orders are received to justify the substantial investment needed. Vestas says that the energy taken to produce the turbine would be paid back within ten months of installation.

Wind power in perspective

In the EU in 2009 renewable energy and wind accounted for 7% and 2% respectively of energy production, compared with coal at nearly 25%. Governments have agreed to increase energy production to 13% from renewable sources by 2020.
The potential added capacity of renewable energy in the EU accounts for two thirds the capacity available for all energy sources, and Vesta hopes to make wind the driving force behind the move towards 10% energy from wind by 2020.
"Seeing the positive indications from governments worldwide, and especially from the UK, to increase the utilization of wind energy is indeed very promising. We look forward to this new turbine doing its part in making these political targets a reality," said Vestas CEO Ditlev Engel.
http://www.gizmag.com/vestas-v164-wind-turbine/18319/

[NUMERATZI]

Ea diache!

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New solar-thermal device harnesses heat and light

By Steven Hondrogiannis
00:52 April 7, 2011

2 Pictures


Wake Forest University researchers say a new solar thermal device could deliver up to 40 percent savings to the cost of heating
Image Gallery (2 images)

Researchers at Wake Forest University have developed a new type of polymer solar-thermal device that combines photovoltaics with a system that captures the Sun's infrared radiation to generate heating. By taking advantage of both heat and light, researchers say the device could deliver up to 40 percent savings on the cost of heating, as well as helping reduce power bills by producing electricity.
The hybrid cell is designed with an integrated array of clear tubes, five millimeters (approx 1/4 inch) in diameter. Lying flat, visible sunlight shines into the clear tube which is filled with an oil blended with a proprietary dye, heating the oil which then flows into a heat pump to transfer the warmth inside a home.
Electrical current is produced via a polymer photovoltaic sprayed onto the back of the tubes.
The result is a solar-thermal device with an impressive 30 percent conversion efficiency.
In comparison to flat solar cells, the tube design also has the advantage of being able to capture light at oblique angles, so it can accumulate power for a much longer stretch in the day and be more readily integrated into building materials – it could be produced to resemble a roofing tile for example.
The research team aims to produce a 3 foot square solar thermal cell over the coming months, a key step in bringing the technology closer to market.
"It's a systems approach to making your home ultra-efficient because the device collects both solar energy and heat," said David Carroll, Ph.D., director of the Center for Nanotechnology and Molecular Materials at Wake Forest University. "Our solar-thermal device takes better advantage of the broad range of power delivered from the sun each day."
http://www.gizmag.com/solar-thermal-cell/18346/

[NUMERATZI]

Ojala que esto salga a la luz y ya se olviden del gasoducto ese ya. Con el calor y sol que hace aqui usando eso tendremos aqui todo el timpo enedremos energia pronto.

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GE Will Build the United States’ Largest Solar Panel Factory

by Rebecca Paul, 04/07/11



GE has just announced their plans to build the largest solar panel factory in the U.S. The company will spend 600 million dollars on the new factory and their goal is to produce of 400 megawatts of thin-film solar annually, by the time they open for business in 2013. GE’s solar panels with be composed of the same thin layers of cadmium telluride currently used by their largest competitor First Solar, but for nearly less than a third of the cost.


GE has become one of the world’s primary manufacturers of wind turbines, and according to Victor Abate, Vice President of GE’s renewable energy business, the company will continue to actively invest in high-tech solar products to advance their position in the renewable energy industry.GE’s first step toward building their new factory has included the recent acquisition of PrimeStar Solar located in Arvada, Colorado.
Abate relays, “The biggest challenge for solar is the cost of energy. For every point you can move [higher] in efficiency, you reduce the cost of the system by 10%.” To counter this issue PrimeStar Solar is seen as a major asset to GE. The company has been able to produce a CdTe thin-film panel with a record-breaking efficiency of 12.8%. The cadmium telluride thin-film also proves to be cost efficient, reducing production costs from $1.20 a watt (the cost of traditional silicon solar panels) to just $.80 a watt.
GE has stated that worldwide demand for solar products is expected to grow by 75 gigawatts over the next five years. With these focused investments GE is hoping to capitalize on the growth. Thus far they already have 100 megawatts worth of orders from utility-scale solar customers in the U.S.

http://inhabitat.com/ge-will-build-t...united-states/

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OFFSHORE WIND ENERGY MEETS OFFSHORE WIND ENERGY STORAGE.


by Bruce Mulliken, Green Energy News


Eventually the United States will get its first offshore wind farm. No one is taking bets as to when it will go online. There have been many proposals, but so far resistance onshore has kept those projects from being built.
Still, wind resources are much better offshore than on and those windy resources are often near heavily populated areas that will be able and willing to consume electricity generated by those reliable ocean breezes.
As with many relatively expensive technologies it’s not such a bad thing to be a late adopter. Early adopters make and have to correct mistakes at a high cost. Early adopters too have only earliest versions of the technology to work with. Late adopters, on the other hand, learn from the mistakes of early adopters and need not repeat them. Late adopters also get to use newer, more sophisticated versions of the technology in question.
Offshore wind is one of those relatively expensive technologies that it’s OK to be a late adopter.
When U.S. offshore wind builders finally get around to planting the first turbine in the ocean bottom (or perhaps floating turbines in deep water over the horizon) they’ll have a better idea of the costs, know exactly how to install them and they’ll have access to far more powerful turbines than those used in the first offshore wind farms in Europe. The U.S. will benefit by being slow to adopt offshore wind, but the time has come to embrace the technology; wind developers know this, so does the U.S. government.
Even as dollars are being pinched in Washington, the Department of Energy has put aside $50.5 million for projects that support offshore wind energy development. The Department of the Interior too, in its Smart for the Start program, has given a hand to offshore wind development by designating four areas along the Mid-Atlantic coast to be on the fast track for regulatory approval.
The funding being offered by DOE can be used for the development of innovative wind turbine design tools and hardware to provide the foundation for a cost-competitive and world-class offshore wind industry in the United States (up to $25 million over 5 years); for baseline studies and targeted environmental research to characterize key industry sectors and factors limiting the deployment of offshore wind ( up to $18 million over 3 years); and for the development and refinement of next-generation designs for wind turbine drivetrains (up to $7.5 million over 3 years).
The Department of the Interior has chosen areas on the Outer Continental Shelf offshore Delaware (122 square nautical miles), Maryland (207), New Jersey (417), and Virginia (165) to receive early environmental reviews that will help to lessen the time required for review, leasing and approval of offshore wind turbine facilities.
Government isn’t alone in seeking to develop offshore wind.
The U.S. branch Spain’s Gamesa, in partnership with the largest shipbuilder in the U.S., are gearing up to join the growing global offshore wind industry. Together, Gamesa North America and Northrop Grumman Corporation have officially launched the National Offshore Wind Technology Center in Hampton Roads, Virginia.
Hampton Roads, at the mouth of the Chesapeake Bay, is the metropolitan area that surrounds the body of water of the same name. The area is has a commercial seaport but also includes the huge Norfolk Navy Base and other government facilities. Hampton Roads is also near the areas set for fast-track regulatory approval by the Interior Department. The Center could feasibly become the hub of a U.S. East Coast offshore wind industry. The partnership brings together Gamesa’s 15-plus years of wind turbine building experience and Northrop Grumman Shipbuilding’s broad experience, including the company’s shipbuilding operations in the seaport.
The first project at the Center will be to build prototypes of Gamesa’s 5-megawatt wind turbine engineered for the harsh environment of the oceans. Two prototype turbines will be built, one onshore and one offshore for comprehensive validation testing. The expected completion date is the fourth quarter of 2012.
After testing the turbines will be marketed globally.
Like onshore wind, energy generated offshore but not sold needs to be stored for later consumption if the technology is to compete with conventional energy sources that operate 24/7.
Without obstructions, winds offshore, including any large body of water, can be stiffer and stronger than winds onshore. Winds that blow lightly onshore even in the middle of the night can be howling offshore. Overnight breezes are a source of energy gone to waste. Right now energy storage is one of those technologies that is in the early (very early) stages of mass adoption.
Offshore wind farms, however, because they are, well, offshore in water, have the potential to utilize a natural energy storage medium: the pressure of water.

Hydrostor, of Toronto, Ontario, is working with engineering researchers at the University of Windsor, on a concept to store energy from offshore wind turbines in the form of compressed air.
The concept goes something like this: Wind energy generated at off-peak hours and not sold would be used to power compressors that would pump air into marine salvage bags moored to the bottom with granite slabs. Like big underwater balloons each bag would be capable of storing 50 cubic meters of compressed air. Compressed air would be released whenever needed to turn generators to make electricity to be sold on the power grid. The pressure of the surrounding water would keep pressure high in the bags as the air was being released. Simple enough.
A project to install 225 bags at a planned Lake Ontario offshore wind farm has a number of hurdles to clear such as an environmental assessment before it can go ahead.
http://www.green-energy-news.com/arc.../20110012.html

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Chicago’s Willis Tower to Become a Vertical Solar Farm

by Andrew Michler, 03/21/11[FONT=verdana,geneva,lucida,'lucida grande',arial,helvetica,sans-serif][/FONT]


Chicago’s iconic Willis Tower (formally the Sears Tower) is set to become a massive solar electric plant with the installation of a pilot solar electric glass project. The high-profile project on the south side of the 56th floor will replace the windows with a new type of photovoltaic glass developed by Pythagoras Solar which preserves daylighting and views while reducing heat gain and producing the same energy as a conventional solar panel. The project could grow to 2 MW in size — which is comparable to a 10 acre field of solar panels — turning North America’s tallest building into a huge urban vertical solar farm.













The project is a collaboration between the tower’s owner and the manufacturer to prove the viability of the building integrated photovoltaic (BIPV) system, which will also save energy by reducing heat gain and cooling costs. The new windows, dubbed high power density photovoltaic glass units (PVGU), are a clever hybrid technology that lays typical monocrystalline silicon solar cell horizontally between two layers of glass to form an individual tile. An internal plastic reflective prism directs angled sunlight onto the solar cells but allows diffuse daylight and horizontal light through. Think of it as a louvered shade which allows for views but cuts out the harsh direct sun.
The manufacturer claims that the vertically integrated solar cells will produce the same amount of energy as normal rooftop-mounted solar panels. This is great news for cities that have precious little rooftop space and towering walls of glass. The product is also a potential breakthrough in energy efficiency in glass towers, where solar heat gain is the bane of energy-efficient design.

http://inhabitat.com/chicagos-willis...al-solar-farm/

[Gueo_pr_19]

Una buena fuente de energia renovable q no he visto q se hable mucho y no se si lo han dicho por aqui es la Digestion Anaerobica. La Digestion anaerobica es el proceso en el cual microorganismos descomponen los desperdicios naturales de animales y humanos para crear metano y dioxido de carbono enriquesido en metano los cuales forman biogas y se puede utilizar para combustible como el gas natural.

Puede q las plantas de tratamiento en PR utilizen los digestores para tratar el agua de alcantarilla... pero no se q se hace con el metano... y cuando pasan por una planta de tratamiento y huelen el olor a mie$^@... eso es el metano.

[NUMERATZI]

esconde mas lo de mier &$ . Jajaj es pa que no te regañen pq la a ya es muy reconocida y pues se puede saber que ahi dice mie.....
Jajaj es vrdd. Huelen super mal!
El metano no produce emiciones?? :O Aunque no me importa tanto eso por que es verde de donde sale.
Aqui deberian utilizar el metano enves del gas que ira por el gasoducto. El metano lo puedes sacar del POPO que diariamente va por nuestras tuberias y ahi creo que habria energia gratuita!

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Google invests US$168 million in world’s largest solar power tower plant

By Darren Quick
00:56 April 13, 2011



2 Pictures



Model rendering of ISEGS, the world's largest solar power tower being built in California
Image Gallery (2 images)



Google has chipped in a US$168 million investment in what will be the world's largest solar power tower plant. To be located on 3,600 acres of land in the Mojave Desert in southeastern California, the Ivanpah Solar Electric Generating System (ISEGS) will boast 173,000 heliostats that will concentrate the sun's rays onto a solar tower standing approximately 450 feet (137 m) tall. The plant commenced construction in October 2010 and is expected to generate 392 MW of solar energy following its projected completion in 2013.
Although solar power tower development is currently less advanced than the more common trough systems, they offer higher efficiency and better energy storage capabilities. Parabolic trough systems consist of parabolic mirrors that concentrate sunlight onto a Dewar tube running the length of the mirror through which a heat transfer fluid runs that is then used to heat steam in a standard turbine.
Solar power tower systems such as the ISEGS on the other hand focus a large area of sunlight into a single solar receiver on top of a tower to produce steam at high pressure and temperatures of up to 550 ° C (over 1,000° F) to drive a standard turbine and generator. The ISEGS also uses a dry-cooling technology that reduces water consumption by 90 percent and uses 95 percent less water than competing solar thermal technologies. Water is also recirculated during energy before being reused to clean the plant's mirrors.


Overshadowing the 20 MW PS20 solar power tower plant in Spain, the scale of ISEGS can't be overstated. It will be the first large-scale solar power tower plant built in the U.S. in nearly two decades and will single-handedly almost double the amount of commercial solar thermal electricity produced in the U.S. today and nearly equal the amount of total solar installed in the U.S. in 2009 alone.
The entire complex will consist of three separate plants developed by BrightSource Energy that will be built in phases between 2010 and 2013. The energy generated from all three plants will be enough to supply more than 140,000 homes in California during peak usage hours, with the project contracted to provide 1,300 MW to Southern California Edison and 1,310 MW to Pacific Gas and Electric Company.
Google says it has now invested over $250 million in the clean energy sector but its $168 million investment in the ISEGS is the company's largest investment to date. The size of the investment reflects Google's faith in the technology and it hopes that other companies will follow its example and make similar investments in renewable energy.
http://www.gizmag.com/google-invests...r-tower/18383/

[Saavedra_LuisR]

^Asi es que tienen que ponerse a invertir en energia renovable.

[NUMERATZI]

eso SI es energia renobable. No un gasoducto Via Verde como dice fortuño.
Lo de verde fue para cogernos a todos de bobo.

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BREAKING: Solar Power Breakthrough Could Render Photovoltaic Cells Obsolete

by Laura K. Cowan, 04/14/11




Researchers at the University of Michigan have made a discovery about the behavior of light that could change solar technology forever. Stephen Rand, a professor in the departments of Electrical Engineering and Computer Science, Physics and Applied Physics and William Fisher, a doctoral student in applied physics, discovered that light, when traveling at the right intensity through a material such as glass that does not conduct electricity, can create magnetic fields that are 100 million times stronger than previously thought possible. In these conditions, the resulting magnetic field is strong enough to rival a strong electric effect. The result is an “optical battery, which could lead to “a new kind of solar cell without semiconductors and without absorption to produce charge separation”, according to Rand.


Rand revealed the research in a paper published in the Journal of Applied Physics. Instead of requiring semiconductor processing, the new technique would only require “lenses to focus the light and a fiber to guide it,” according to Fisher. “Glass works for both. It’s already made in bulk, and it doesn’t require as much processing. Transparent ceramics might be even better.” Rand and Fisher predict that they could achieve efficiency with this new technology that is equivalent to today’s commercial-grade solar cells.
With efficiencies equal to current commercial-grade panels, the new solar tech could lead to more affordable home-based arrays that integrate more seamlessly into your home–maybe even directly into your windows?

http://inhabitat.com/breaking-solar-...ells-obsolete/

[Bori427]

Numeratzi, deja la politica a un lado en temas como estos.

[luisr]

Hace muchos años Bacardí en Cataño utiliza digestores anaeróbicos para generar metano y lo usan para operar las calderas de la destilería. Ellos venden o vendían esa tecnología y se que la Cervecería India (ahora Cervecera de PR) tiene un sistema similar aunque más pequeño. También se que el vertedero municipal de Humacao operado por Waste Management tiene uns sistema de recuperación de gases pero ahora mismo no tienen a quien venderle el gas y lo que hacen es quemarlo en un "flare".

[NUMERATZI]

Esos gases los deberian usar ellos en un generador para producir surplus energy para que corra en riversa por el grid y energia electrica les pague.

[Ultramatic]

April 14, 2011
Duke Energy to Deploy 36-Megawatt Battery Storage System at Texas Wind Farm.



Duke Energy intends to store electricity generated at its Notrees Windpower Project in west Texas using an energy storage and power management system developed by Austin-based Xtreme Power.
In November 2009, Duke Energy announced plans to match a $22 million grant from the U.S. Department of Energy (DOE) to install large-scale batteries capable of storing electricity produced by the company's 153-megawatt (MW) Notrees wind farm, located in Ector and Winkler counties. After due diligence, Duke Energy chose Xtreme Power to design, install and operate a 36 MW-capacity Dynamic Power Resource(TM) system at the wind farm. When complete, the battery storage system will be one of the largest of its kind in the world and the largest at a wind farm.
This system will store excess wind energy and discharge it whenever demand for electricity is highest - not just when wind turbine blades are turning. In addition to increasing the supply of renewable energy during periods of peak demand, Xtreme's Dynamic Power Resource(TM) solution will help stabilize the frequency of electricity traveling throughout the power grid.
Duke Energy will work closely with the Energy Reliability Council of Texas (ERCOT) to integrate the wind power and battery storage solution into the state's independent power grid. The Electric Power Research Institute (EPRI) will advise the project team, collect data and help assess the potential for broader adoption of energy storage solutions throughout the industry. Results from the storage project at Duke Energy's Notrees wind farm will be shared publically through the DOE's Smart Grid Information Clearinghouse.

The DOE grant was made possible by the American Recovery and Reinvestment Act of 2009. In January 2011, DOE and Duke Energy agreed upon the terms and conditions of the grant. Duke Energy will elect to receive the matching funds for the energy storage and management solution once the company has completed its due diligence.
Duke Energy is targeting an in-service date for the battery storage system by late 2012. (4/14/11)
Links:
Duke Energy
http://www.duke-energy.com
Xtreme Power
http://www.xtremepower.com

http://www.green-energy-news.com/nws.../apr11018.html

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Solar-energy development slated for shuttered landfills

By : JOHN MARINO
marino@caribbeanbusinesspr.com
Edition: April 14, 2011 | Volume: 39 | No: 14

Effort promises dollars for municipalities; renewable energy to meet island’s new mandatory public policy; goal is to have first project operational next yearThe Environmental Quality Board (EQB) is leading a joint federal-commonwealth initiative that aims to develop solar-energy projects on shuttered landfills across the island.
The effort will contribute to a new public policy of the Gov. Luis Fortuño administration that requires that 20% of Puerto Rico’s power come from renewable sources by 2030 and also will make the most of what could be Puerto Rico’s most limited resource, its land, EQB President Pedro Nieves Miranda told CARIBBEAN BUSINESS in an exclusive interview.
“We are very excited about this initiative. We have received great support from federal and local agencies, as well as mayors,” Nieves Miranda said. “Once landfills close, very few do something productive. It’s time we rescue this resource and put it to use.”
Some 30 landfills were closed in Puerto Rico in the 1990s, and another five are in the process of closing or will be shuttered in the near future. Most are owned by cash-strapped municipalities.
Once closed, the landfills must be capped and maintained to meet federal standards, a burden that can cost several hundred thousand dollars a year, Nieves Miranda said. Solar projects could recoup those costs and also start making money for island towns.
Solar technology is being looked at in tropical Puerto Rico, and the infrastructure required is one of the few that can be built on land occupied by a shuttered landfill, the EQB chief said. For example, large excavations can’t be attempted on closed landfills without damaging their caps.
An interagency team has been doing site visits on landfills to study their geographical and solar characteristics, access to the island’s power grid and other technical issues to determine the viability of a solar project at each site.
The team is also exploring project financing and whether existing grants or incentives could help make the projects viable. The administration is looking to attract private industry to develop the solar projects, perhaps as public-private partnerships (PPPs) with municipal governments that own the landfills. The power would then be sold to the Puerto Rico Electric Power Authority (Prepa), or used by the municipality to supply its own needs or sell to third parties.
“At this point, a broad range of alternatives is being explored,” the EQB chief said. “Our focus remains on determining the viability of solar technology at each site.”
Solar projects probably won’t be viable at all sites, because of terrain, solar capture and other factors, and the size of the landfills varies greatly. Nieves Miranda estimated that a landfill solar project could deliver anywhere from four megawatts to 11 megawatts.
The goal is to have a project operational next year. So far, the EQB-led initiative has visited 10 landfills, and Aguadilla Mayor Carlos Méndez has expressed interest in such a project in his town.
http://www.caribbeanbusinesspr.com/c...=5142&ct_id=90

[InitiateRenew]

Originally Posted by NUMERATZI

eso SI es energia renobable. No un gasoducto Via Verde como dice fortuño.
Lo de verde fue para cogernos a todos de bobo.

Segunda vez que te pido por favor te limites a comentarios sobre el proyecto y no a criticas no constructivas en contra de cualquier cosa, grupo o persona en la cual no estas de acuerdo.

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Solar on the Water



Elvin Batz, an installer at SPG Solar, checks the pontoon structure and panels of a floating solar array in an irrigation pond in Petaluma, Calif.


By TODD WOODY

Published: April 19, 2011



PETALUMA, Calif. — Solar panels have sprouted on countless rooftops, carports and fields in Northern California. Now, several start-up companies see potential for solar panels that float on water.


Already, 144 solar panels sit atop pontoons moored on a three-acre irrigation pond surrounded by vineyards in Petaluma in Sonoma County. Some 35 miles to the north, in the heart of the Napa Valley, another array of 994 solar panels covers the surface of a pond at the Far Niente Winery.
“Vineyard land in this part of the Napa Valley runs somewhere between $200,000 and $300,000 an acre,” said Larry Maguire, Far Niente’s chief executive. “We wanted to go solar but we didn’t want to pull out vines.”
The company that installed the two arrays, SPG Solar of Novato, Calif., as well as Sunengy of Australia and Solaris Synergy of Israel, are among the companies trying to develop a market for solar panels on agricultural and mining ponds, hydroelectric reservoirs and canals. While it is a niche market, it is potentially a large one globally. The solar panel aqua farms have drawn interest from municipal water agencies, farmers and mining companies enticed by the prospect of finding a new use for — and new revenue from — their liquid assets, solar executives said.
Sunengy, for example, is courting markets in developing countries that are plagued by electricity shortages but have abundant water resources and intense sunshine, according to Philip Connor, the company’s co-founder and chief technology officer.
Chris Robine, SPG Solar’s chief executive, said he had heard from potential customers as far away as India, Australia and the Middle East. When your land is precious, he said, “There’s a great benefit in that you have clean power coming from solar, and it doesn’t take up resources for farming or mining.”
Sunengy, based in Sydney, said it had signed a deal with Tata Power, India’s largest private utility, to build a small pilot project on a hydroelectric reservoir near Mumbai. Solaris Synergy, meanwhile, said it planned to float a solar array on a reservoir in the south of France in a trial with the French utility EDF.
MDU Resources Group, a $4.3 billion mining and energy infrastructure conglomerate based in Bismarck, N.D., has been in talks with SPG Solar about installing floating photovoltaic arrays on settling ponds at one of its California gravel mines, according to Bill Connors, MDU’s vice president of renewable resources.
“We don’t want to put a renewable resource project in the middle of our operations that would disrupt mining,” Mr. Connors said. “The settling ponds are land we’re not utilizing right now except for discharge and if we can put that unproductive land into productive use while reducing our electric costs and our carbon foot footprint, that’s something we’re interested in.”
Mr. Connors declined to discuss the cost of an SPG floating solar array. But he noted, “We wouldn’t be looking at systems that are not competitive.”
SPG Solar’s main business is installing conventional solar systems for homes and commercial operations. It built Far Niente’s 400-kilowatt floating array on a 1.3-acre pond in 2007 as a special project and has spent the last four years developing a commercial version called Floatovoltaics that executives say is competitive in cost with a conventional ground-mounted system.
The Floatovoltaics model now being brought to market by SPG Solar is the array that bobs on the surface of the Petaluma irrigation pond.
“We have been able to utilize a seemingly very simple system, minimizing the amount of steel,” said Phil Alwitt, project development manager for SPG Solar, standing on a walkway built into the 38-kilowatt array.
“With steel being so expensive, that’s our main cost,” Mr. Alwitt said.
Long rows of standard photovoltaic panels made by Suntech, the Chinese solar manufacturer, sit tilted at an eight-degree angle on a metal lattice fitted to pontoons and anchored by tie lines to buoys to withstand wind and waves.
The array, which is not yet operational, will be hooked up to a transmission line through a cable laid under the pond bed. Mr. Alwitt said that when the array is completed, 2,016 panels would cover most of the pond’s surface and generate one megawatt of electricity at peak output.
He noted that the cooling effect of the water increased electricity production at the Far Niente winery by 1 percent over a typical ground-mounted system.


SPG Solar executives said an environmental engineering firm that evaluated its technology concluded that water evaporation under the floating arrays decreased by 70 percent. The companies also say that their systems inhibit destructive algae growth by blocking the sunlight the algae need to grow.


David L. Sedlak, a professor of civil and environmental engineering at the University of California, Berkeley, agreed that the floating solar power plants could prove useful in controlling algae.
“Irrigation ponds have the potential to become algal sources and algae can cause all sorts of issues,” said Dr. Sedlak, co-director of the university’s Berkeley Water Center. But he said he doubted that stemming evaporation would be a big selling point for floating solar panels since irrigation ponds did not lose that much water to evaporation.
Solar entrepreneurs had hoped to persuade the California State Water Project to cover the 400-mile California Aqueduct with photovoltaic panels. The panels could then generate electricity in the canal that irrigates the agricultural empire of the Central Valley and helps supply water to 25 million Californians.
Solaris Synergy, the Israeli firm, claims that installing its floating solar arrays on the aqueduct could produce up to two megawatts of electricity per mile. And SPG Solar executives said they held preliminary discussions with state officials about putting solar panels on the aqueduct.
“We think there’s a huge potential,” Mr. Robine said.
Ralph Torres, deputy director of the state water project, said he had recently spoken with Solaris, the latest of many companies that he said had approached his agency over the years about installing solar panels.
“You would really have to anchor these solar arrays so they wouldn’t float away,” Mr. Torres said. “If you do spring a leak and have to go in quickly these panels would be in the way and you might damage or destroy them when responding to an emergency.”
“A better application would be on a reservoir,” he added.
That is Sunengy’s strategy. Mr. Connor said the company was looking to developing countries to turn hydroelectric dams and village reservoirs into giant batteries.
“Any solar power you generate on the dam allows you to feed the transmission line and save water in the dam for use on rainy days or at night,” he said.
Sunengy’s plan would deploy rafts of solar units that use a plastic lens to track the sun and concentrate sunlight on small photovoltaic cells that use less expensive silicon than conventional cells. In high winds, the lens stows under the water.
“If you have a drought on a hydroelectric dam, your asset is dead,” Mr. Connor said. “If you have solar power on that dam, you can continue to generate electricity.”



http://www.nytimes.com/2011/04/20/bu...anted=2&ref=us