Friday, June 22, 2012

Latest from: CleanTechnica

Latest from: CleanTechnica

Link to CleanTechnica

Maryland Going Green as Its Clean Energy Industry Expects Great Things

Posted: 22 Jun 2012 08:13 AM PDT

 
Maryland Clean Energy Industry

A recent industry survey in Maryland found that the state's clean energy industry is adding green jobs this year despite the national economy being slow overall. The clean energy industry is apparently doing rather well – in other words, let's stop trying to policy it to death, guys, and pay attention to how clean tech can create and sustain local jobs.

The survey was conducted by the Maryland Clean Energy Center, which has been online since 2008. The MCEC polled just under 200 businesses registered with the MCEC between May 1 and June 15 (most of which are headquartered in Maryland), and assessed economic impact, the state of the industry, the effects of current clean energy policy, and whether or not there's an opportunity for competitive electricity suppliers.

It Makes A Difference

Most of the businesses surveyed are currently fairly tiny – less than 25 employees, although there were a number with more than 100 – but nearly all of them are planning to maybe hire more people and definitely not let anyone go. MCEC Executive Director Kathy Magruder applauds the current state of small-business clean tech:

"Maryland's clean energy industry is a significant bright spot in this state's economy. Despite the overall national recession, our green economy is strong and growing fast."

The respondents also agreed with Magruder – most of them felt that Maryland was a great place for clean energy, with the state of the industry being pretty strong, or at least better than other states, and know that they can shop around for the greenest possible electricity supplier.

Pay Attention To The Little Things

Part of the Maryland's current success with its clean tech is definitely down to the industry in general managing to reach people in the right way; the vast majority of the respondents reported that their primary customers were homeowners and businesses (as opposed to, say, the government, or the military, or an entrepreneur).

Clean tech policy in Maryland, on the other hand, is apparently both super awesome and very frustrating – tax breaks have done great things to help a lot of these currently-small businesses to expand, but the vast majority of respondents weren't sure about policy at the federal level, the state level, or even the local level, and thought that could be problematic.

Most respondents also wanted more, more, more for the state's renewable energy portfolio standard, but a funny thing pops up here: most of the respondents hadn't reached out to their state delegate or senator on the issue. The takeaway there is to do something about it — if Maryland (or any other state) wants clean energy success, you (yes, you) need to go make it happen. So far, so good – let's make it better.

Questions or comments? Let us know below. For those of you who want to see the specific results, you can get all the graphs and stats by clicking here.

Source: Maryland Clean Energy Center 
Image Credit: Fletcher6


Control Your Bulbs with Your Smartphone

Posted: 22 Jun 2012 08:01 AM PDT

 
Home automation technology manufacturer INSTEON has introduced the world’s “first-to-market networked remote control dimmable LED light bulb.”

"For years, home automation has controlled light fixtures with plug-in lamp modules, wire-in switches and keypads. But, until now, no one has controlled the bulb itself. It's exciting to be the first to introduce a new product to the world," said Joe Dada, chief executive officer, INSTEON.

Link one INSTEON LED Bulb to as many controllers as you want—including keypads, motion sensors, door sensors or even your smartphone. Or, link multiple bulbs to a single controller and turn them all on or off at the same time.

The INSTEON LED Bulb is described by the manufacturers as being simple to set up, with intuitive control and easy linking to any INSTEON controller. The the bulb will obviously be controlled by a remote control, but it can also be controlled by a free app for iOS and Anrdoid smartphones or tablets, a must-have feature in today’s technology rich field.

The bulb is fully dimmable, can be used in any number of situations and set ups, and will retail for $29.99. A video demonstration was provided by INSTEON and can be seen in the YouTube video below.

Source: INSTEON


Japan vs Gertalia — A Solar Country Comparison

Posted: 22 Jun 2012 07:42 AM PDT

This short post will compare two countries to showcase what is possible with solar energy technology. The two countries in question are Japan and the fictitious nation of “Gertalia.”

Japan is of course a pioneer in solar technology. Perhaps the country will even become a rising star of solar energy once again after the Japanese government’s decision to adopt an aggressive Feed-in Tariff law modeled after the German example that will go into force on July 1st. There is little doubt that this decision will boost solar power installations tremendously, but the question is how much and how fast?

"Gertalia" is obviously an imaginary country which is the result of squashing Germany and Italy together, something the earth has been working on for millions of years by pushing the tectonic plates in that direction.

Why compare Japan and "Gertalia"?

Because they "almost" have the same population, a similar-sized modern economy with a strong and diverse manufacturing base, and… they even look "slightly" similar on the map (needs a little imagination).

As you can see, both “countries” also consume about the same amount of electricity every year. They also have a very similar portion of conventional hydroelectric power production in their power generation mix. But when it comes to electricity generation from other renewable sources, they are worlds apart. In fact, in 2011, “Gertalia” produced more electricity from solar energy than Japan did from all non-hydro renewable sources!

A Different Look at Numer One, Two, & Three

Last year, Germany, Italy and Japan were the three leading countries when it comes to total photovoltaic power capacity. While being in third place doesn’t sound too bad, the Japan–”Gertalia” comparison paints a very clear picture, especially considering the fact that Japan was number one until 2004, even ahead of Germany by 30 MW!

 

 

Moving Forward

Japan certainly has a long way to catch up, but the aggressive FiT should be more than helpful. Considering that predictions of renewable energy growth tend to underestimate what’s possible, we might all be in for a surprise as to how fast Japan will crank up solar installations, especially when there is so much untapped renewable energy potential.

As for Gertalia, the near future is a bit uncertain. Earlier this year, the German and Italian governments proposed deep cuts to solar FiTs. On the other hand, both governments also faced resistance and had to paddle back on their cuts recently. While we might not see an additional 16.8 GW in Gertalia this year, it could still end up being in the territory of 10 GW.


Rio+20: More than 50 Countries, $50 Billion in Pledges for UN’s “Sustainable Energy for All”

Posted: 22 Jun 2012 07:36 AM PDT

Confounding pessimistic expectations, UN Secretary General Ban-ki Moon on the opening day of the Rio+20 UN Conference on Sustainable Development announced encouraging news regarding the UN’s “Sustainable Energy for All” program.

More than 50 governments have launched new clean energy strategies, while private investors have pledged to invest more than $50 billion to reach the program’s goal of doubling renewable energy production and energy efficiency gains while providing all people access to modern electricity services by 2030, The Chicago Tribune reports.

The UN Secretary General continues to lead the call for nations around the world to aggressively pursue the goal of making the transition from fossil fuels to cleaner, renewable energy resources. “I have often said that sustainable energy is the golden thread that weaves together the economy, the environment and equity,” he stated in his Rio+20 opening address.

Green Growth’s the Right Kind of Growth

“The argument is simple: when we invest in green growth, we benefit the economy and the environment. When we innovate clean technologies, when we reduce, recycle and even recover energy from waste, when we invest in education for advances in sustainability. Countries around the world see the benefit of this approach.”

Governed by an interrelationships that do not recognize national borders, the UN must be the organization that “provides the overarching framework for our efforts,” he added by recalling Danish Prime Minister Helle Thoming-Schmidt’s call on international leaders to enact a green transition.

It’s anticipated that the “Sustainable Energy for All” initiative will ultimately benefit more than 1 billion people. The benefits will be substantial and multifaceted, impacting the lives of everyday people, as well as businesses, in numerous ways, according to Secretary General Moon.

Some 1.3 billion people do not have access to electricity, while 2.7 billion rely on wood, dirty fuels or animal waste for cooking and heating, he noted.

“I would add that green growth means more than hope and confidence — it means jobs, innovation, cleaner air and more liveable cities. Green growth is central to why we are here in Rio: to lift people out of poverty and protect the global environment.”


Germany Moving Away from Solar Parks to Rooftop Schemes

Posted: 22 Jun 2012 07:13 AM PDT

According to a recent McKinsey study, more than half of all installed solar power generation capacity worldwide could be from rooftop setups under which people generate their own electricity, rather than buying it from a typical centralized power plant.

Germany already has half of the world’s photovoltaic solar power generation capacity, and it has been aggressively pursuing solar power with great success (as our regular readers are well aware).

“Those companies who survive the current consolidation wave will experience a bright future. Especially the rooftop segment and downstream business models are expected to drive the industry forward,” stated Tobias Rothacher, photovoltaic industry expert at Germany Trade & Invest in Berlin.

The global solar industry is struggling with the fact that solar panel costs are being driven down by increased competition and economies of scale, causing their prices and profit margins to fall.

However, worldwide solar power generation capacity is expected to increase by another 400 GW to 600 GW.

“Germany has supported own consumption of solar power for years. The coming grid parity era is ushering in an era of new business opportunities. We expect Germany to continue to be the top business location, as innovations and industry standards are developed here,” according to Tobias Rothacher.

Rooftop Solar Schemes Have Potential Reliability and Cost Benefits (when you look at the big picture)

In rooftop solar schemes, solar panels are spread out over a much larger area than they would be at a typical solar power plant, at which they are normally squeezed into the smallest possible space.

Clouds are able to cover more solar panels during one pass-over if they are closer together. Spreading solar panels out over a larger area means that fewer of them will be shaded by clouds and the overall system’s power production will not decrease nearly as much.

 

 

About the cost benefit: the more solar panels there are spread over a good distance, the greater the reliability, and the less solar panels will need to be backed up with either natural gas generators or batteries, both of which are costly in multiple ways.

Source: PR Newswire 
Photo Credit: h080


IKEA to Use Rooftop Solar Power Plants in China

Posted: 22 Jun 2012 07:05 AM PDT

 
In addition to the other announcement I just posted about, IKEA has announced that, as part of its goal to use only renewable energy to power its buildings, it will partner with the Chinese clean energy company Hanergy to install solar panels on IKEA buildings in China.

ikea china store

Once complete, the solar project is expected to provide 10% to 15% of the power requirements of IKEA’s buildings in China, and 100% of the power required by its distribution centres. This is expected to reduce carbon dioxide emissions by 6,000 tons per year.

This project is even extended to IKEA’s suppliers.

"IKEA has a long-term commitment to use 100 percent renewable energy to power our buildings and this is an important and significant step towards reaching that goal. Not only will we harness the sun to help power our stores and other buildings across China, but we will also extend the scope of the project over the coming year to our supply base across the country; enabling them to utilise an affordable and reliable supply of clean energy," said Steve Howard, Chief Sustainability Officer, IKEA Group.

Worldwide, more than half of IKEA’s energy comes from renewable energy powered generators, primarily wind turbines and solar panels.

"Our partnership with IKEA is an exciting opportunity to promote the smart use of thin-film solar technology as a reliable, clean and alternative source of energy. In the current context of high electricity demand, such initiatives have the potential to relieve pressure on the national grid, support our clients' business and preserve the environment," said Li Hejun, Chairman of Hanergy.

IKEA is not only shifting to renewable energy, though. It is also reducing the energy usage of its stores, which is another integral part of reducing its environmental footprint.

Source: Business Wire
Image Credit: IKEA China store via testing / Shutterstock.com


IKEA US Solar Plans Near 89% with Two More Installations Proposed

Posted: 22 Jun 2012 06:58 AM PDT

 
IKEA, a very large retailer of low-cost household furniture, has announced plans to install solar panels on two more of its United States locations, both of which are distribution centres in the eastern section of the country.

Installation will commence this summer on the IKEA distribution centres in Perryville, Maryland, and Westampton.

The two distribution centres will have a combined 4.92 MW (4,920 kW) of solar electricity generation capacity. The 34,000+ panels are to facilitate the avoidance of 4,509 tons of carbon dioxide, which is the equivalent of removing 802 cars from roads, or providing clean energy to 510 homes annually.

This project is one of many IKEA clean energy projects that we have written about, and IKEA certainly is committed to this whole renewable energy goal that it set. It wants to obtain all of its energy from renewable sources, especially solar and wind, and it is on a fast track to achieving that goal.

An annual power generation of 5,933,200 kWh (5,293.2 MWh or 5.293 GWh) is expected from this project.

"We are excited at the opportunity to increase our U.S. solar presence further with solar energy systems atop these two east coast distribution centers," said Mike Ward, IKEA U.S. president.

IKEA currently has 17 U.S solar system installations, and the two new systems mentioned above will increase its combined generation capacity to 38 MW (38,000 KW).

"With only 44 locations nationwide, we try to contribute whenever and wherever possible to creating a better everyday life for the many. These plans for installing solar panels on the roofs of two additional distribution centers demonstrate that our sustainable commitment extends beyond just stores, into all facets of the retail operations."

Source: Business Wire
Photo Credit: ICMA Photos


My First Solar Panel

Posted: 22 Jun 2012 06:39 AM PDT

 
Over the past few years I have been learning about solar panels, and power plants in general. My next step towards becoming a solar panel expert was the purchase of a 10-watt multicrystalline silicon solar panel. The short circuit voltage is up to 20 volts.

My First Solar Panel

Its efficiency is 10%, meaning that a square meter of these panels generates 100 watts of electric power during sunny weather, assuming typical solar irradiance of 1,000 watts per square metre.

I thought I’d write a bit about my experiences experimenting with this solar panel and what I’ve learned.

The Manufacturer Didn’t Lie

I was delighted to see that the panel generated the full 10 watts of power mentioned by the manufacturer when I took it outside in typical sunny weather. I conducted multiple tests in weather of varying degrees of cloudiness. During one cloudy morning test, when the sun was barely noticeable through the clouds, the panel generated about 40% of its rated generation capacity.

During another test in which the sun was not visible at all, it generated 25% of its nameplate (generation) capacity, 2.5 watts.

Importance of Panel Tilt and Cell Shading

Tilt

During most of my tests, the panel actually generated the most electricity when facing straight upwards, because of the sun’s position. Depending on the sun’s position, the panel will need to be tilted, and sometimes it needs to be pointed straight upwards. The power generated by the panel did vary considerably as I changed its position, so this is clearly important.

As always recommended, if you buy solar panels, ensure that they are placed where it is most sunny, and for the longest periods of time. If you can set up an affordable solar tracker, good for you. These maximize power yield.

Cell Shading

This is one of the most important issues. Never shade a single cell of a solar panel (not even a little). Solar panels are usually made of a string of solar cells connected in series. I demonstrated this with my panel too.

If you are installing your own solar system, I would connect as few panels in series as possible to minimize the effect of this. But, don’t be deceived by the severity of this issue — if you place your panels in a section without shade, this is rarely going to be an issue, unless something splatters on the panel, in which case you would rinse it off.

During winter, you can use a roof rake to remove snow from your solar panels (if you live in a snowy climate).

To be more specific about the above, the first solar cell in the circuit generates electricity, it flows through the second cell, then the third, fourth, etc, until it exits the final cell and is used to charge batteries.

If you shade any of these cells, the electrical resistance of that cell obstructs the flow of current through the entire solar panel, and  reduces the power output of the entire panel significantly.

Rinse off your solar panels periodically (even if it is a just some fruit on them). This maximizes power production.

I will continue to test this solar panel and use it to charge my USB electronics and other science projects for now.


Meet Airwave, from Nest

Posted: 22 Jun 2012 06:30 AM PDT

 
From the people who brought you the world’s sexiest-looking thermostat comes Airwave, a new feature of the Nest Learning Thermostat that purports to be able to reduce air-conditioning runtime up to 30%.

Nest brought out the sexy Nest Learning Thermostat last year to great acclaim, and many in the green and tech communities have followed the company with avid interest. Now, Nest is trying to help you save on your air conditioning by introducing Airwave.

Click to view in PDF

Nest also demonstrated on its site the ins and outs of Airwave:

To understand Airwave, you need to understand your AC.

Your air conditioner is made up of two energy consuming parts: the compressor and the fan. The compressor uses a lot of electricity while the fan uses very little.

Other thermostats keep the air conditioner running until your target temperature is reached, then turn it off. They ignore the fact that the compressor coils can generate cold air for 5-10 minutes after the compressor is off.

Nest's exclusive Airwave technology takes advantage of this fact.

How Airwave works.

Airwave turns the compressor off a few minutes before reaching your target temperature. It then runs the fan alone till it reaches the temperature you want.

What makes Airwave a Nest exclusive is its ability to learn exactly how much cooling can be done with the compressor off. Only Nest automatically shuts off your compressor at the right time to maximize your savings.

Will Airwave work in my house?

While Airwave requires the humidity level inside your home to be low, it works throughout the US – even in areas with high outdoor humidity. This is especially true if your home is relatively new and well-insulated.

The reason Airwave doesn't activate in high indoor humidity is to keep you comfortable. If it's very humid, Nest will run your compressor throughout your cooling cycle to lower the humidity and prevent mold.

When does Airwave activate?

Nest automatically turns on Airwave when interior humidity falls below a certain level. This level is calculated by Nest to be optimal for your home.

When Airwave activates you'll see it on Nest's display.

Source: Nest


New Mathematical Approach Could Simulate Materials for Solar Cells and LEDs

Posted: 22 Jun 2012 06:18 AM PDT

 
Some more cool cleantech news from the MIT News Office:

Disordered materials, such as this slice of amorphous silicon (a material often used to make solar cells), have been very difficult to model mathematically. New mathematical methods developed at MIT should help with such modeling. Image: wikimedia commons/Asad856

A multidisciplinary team of researchers at MIT and in Spain has found a new mathematical approach to simulating the electronic behavior of noncrystalline materials, which may eventually play an important part in new devices including solar cells, organic LED lights and printable, flexible electronic circuits.

The new method uses a mathematical technique that has not previously been applied in physics or chemistry. Even though the method uses approximations rather than exact solutions, the resulting predictions turn out to match the actual electronic properties of noncrystalline materials with great precision, the researchers say. The research is being reported in the journal Physical Review Letters, published June 29.

Jiahao Chen, a postdoc in MIT's Department of Chemistry and lead author of the report, says that finding this novel approach to simulating the electronic properties of "disordered materials" — those that lack an orderly crystal structure — involved a team of physicists, chemists, mathematicians at MIT and a computer scientist at the Universidad Autónoma de Madrid. The work was funded by a grant from the National Science Foundation aimed specifically at fostering interdisciplinary research.

The project used a mathematical concept known as free probability applied to random matrices — previously considered an abstraction with no known real-world applications — that the team found could be used as a step toward solving difficult problems in physics and chemistry. "Random-matrix theory allows us to understand how disorder in a material affects its electrical properties," Chen says.

Typically, figuring out the electronic properties of materials from first principles requires calculating certain properties of matrices — arrays of numbers arranged in columns and rows. The numbers in the matrix represent the energies of electrons and the interactions between electrons, which arise from the way molecules are arranged in the material.

To determine how physical changes, such as shifting temperatures or adding impurities, will affect such materials would normally require varying each number in the matrix, and then calculating how this changes the properties of the matrix. With disordered materials, where the values of the numbers in the matrix are not precisely known to begin with, this is a very difficult mathematical problem to solve. But, Chen explains, "Random-matrix theory gives a way to short-circuit all that," using a probability distribution instead of deriving all the precise values.

The new method makes it possible to translate basic information about the amount of disorder in the molecular structure of a material — that is, just how messy its molecules are — into a prediction of its electrical properties.

"There is a lot of interest in how organic semiconductors can be used to make solar cells" as a possible lower-cost alternative to silicon solar cells, Chen says. In some types of these devices, "all the molecules, instead of being perfectly ordered, are all jumbled up." These disordered materials are very difficult to model mathematically, but this new method could be a useful step in that direction, he says.

Essentially, what the method developed by Chen and his colleagues does is take a matrix problem that is too complex to solve easily by traditional mathematical methods and "approximates it with a combination of two matrices whose properties can be calculated easily," thus sidestepping the complex calculations that would be required to solve the original problem, he explains.

Amazingly, the researchers found that their method, although it yields an approximation instead of the real solution, turns out to be highly accurate. When the approximation is plotted on a graph along with the exact solution, "you couldn't tell the difference with the naked eye," Chen says.

While mathematicians have used such methods in the abstract, "to our knowledge, this is the first application of this theory to chemistry," Chen says. "It's been very much in the domain of pure math, but we're starting to find real applications. It's exciting for the mathematicians as well."

The incredible accuracy of the method, which uses a technique called free convolution, led the team to investigate why it was so accurate, which has led in turn to new mathematical discoveries in free probability theory. The method derived for estimating the amount of deviation between the precise calculation and the approximation is new, Chen says, "driven by our questions" for the mathematicians on the team. "It's a happy accident that it worked out as well as it did," he adds.

"Our results are a promising first step toward highly accurate solutions of much more sophisticated models," Chen says. Ultimately, an extension of such methods could lead to "reducing the overall cost of computational modeling of next-generation solar materials and devices."

David Leitner, a professor of theoretical and biophysical chemistry and chemical physics at the University of Nevada at Reno who was not involved in this work, says the potential practical impact of this research "is great, given the challenge faced in calculating the electronic structure of disordered materials and their practical importance." He adds that the key test will be to see if this approach can be extended beyond the one-dimensional systems described in this paper to systems more applicable to actual devices. "Extension to higher dimensions is critical in assessing the work's significance," he says.

Such calculations "remain a big challenge," Leitner says, and further work on this approach to the problem "could be very fruitful."

In addition to Chen, the team included MIT associate professor of chemistry Troy Van Voorhis, chemistry graduate students Eric Hontz and Matthew Welborn and postdoc Jeremy Moix, MIT mathematics professor Alan Edelman and graduate student Ramis Movassagh, and computer scientist Alberto Suárez of the Universidad Autónoma de Madrid.


Wind Powered Cargo Ship Sails Like a Luxury Yacht

Posted: 22 Jun 2012 03:59 AM PDT

B9 cargo ship uses wind powerA futuristic wind powered cargo ship is in the works, and it sports sails modeled after one of the largest luxury yachts in the world, the Maltese Falcon. If it proves successful, the new B9 cargo ship could usher in a new era of fossil fuel–free technology at a critical time for the shipping industry, which is facing the prospect of soaring greenhouse gas emissions as the global import-export market trends upwards.

Shipping cargo with wind power

The B9 is the brainchild of Ireland-based B9 Shipping, part of the B9 Energy group. The rigid sail design actually predates the Maltese Falcon; called Dyna-rig, the foundational technology dates back to the 1960′s.

The advantages of Dyna-rig over canvas sail are numerous. Aside from durability, the electronically operated system requires no rigging lines or hand operation, and it responds quickly to changing wind conditions.

B9 Shipping notes that the Maltese Falcon has crossed the Atlantic twice and has achieved a top speed of 24.9 knots using a Dyna-rig system.

Sailing on biogas

B9 Shipping also notes that the Maltese Falcon only uses its sails about 61 percent of the time. The yacht’s auxiliary power is provided by biogas, and that’s where the B9 Energy group will come in.

B9 plans to manufacture biogas for the cargo ship primarily from a food waste stream, which will power an “off-the-shelf” Bergen gas engine from Rolls Royce.

 

Next steps to wind-powered cargo ships

The University of Southampton's Wolfson Unit for Marine Technology and Industrial Aerodynamics will be conducting a detailed series of studies as work on the new ship progresses, including economic feasibility as well as performance studies on various hull shapes.

The final design will also take into account the work flow of the shipping industry — namely, loading and unloading cargo.

However, if B9 wants to produce the world’s first fleet of commercially viable wind powered cargo ships, it better get a move on. Last year a company called Eco Marine Power unveiled a rigid sail design for cargo ships that incorporates solar panels, and just last month the University of Tokyo proposed a design for cargo ships powered with low cost metal sails.

Image: Courtesy of B9 Shipping

Follow me on Twitter: @TinaMCasey


All-Carbon Solar Cell Harnesses Infrared Light

Posted: 22 Jun 2012 03:13 AM PDT

 
Here’s some fun and exciting news from researchers at MIT about a new type of photovoltaic device that can harness the heat radiation that most solar cells ignore. Enjoy! (The news was received via email, but it has also been published at the MIT News Office.)

An atomic-force microscope image of a layer of single-walled carbon nanotubes deposited on a silicon surface, as the first step in manufacturing the new type of solar cell developed by an MIT team. Individual nanotubes can be seen in the image. Photo: Rishabh Jain et al

CAMBRIDGE, MA. — About 40 percent of the solar energy reaching Earth's surface lies in the near-infrared region of the spectrum — energy that conventional silicon-based solar cells are unable to harness. But a new kind of all-carbon solar cell developed by MIT researchers could tap into that unused energy, opening up the possibility of combination solar cells — incorporating both traditional silicon-based cells and the new all-carbon cells — that could make use of almost the entire range of sunlight's energy.

"It's a fundamentally new kind of photovoltaic cell," says Michael Strano, the Charles and Hilda Roddey Professor of Chemical Engineering at MIT and senior author of a paper describing the new device that was published this week in the journal Advanced Materials.

The new cell is made of two exotic forms of carbon: carbon nanotubes and C60, otherwise known as buckyballs. "This is the first all-carbon photovoltaic cell," Strano says — a feat made possible by new developments in the large-scale production of purified carbon nanotubes. "It has only been within the last few years or so that it has been possible to hand someone a vial of just one type of carbon nanotube," he says. In order for the new solar cells to work, the nanotubes have to be very pure, and of a uniform type: single-walled, and all of just one of nanotubes' two possible symmetrical configurations.

Other groups have made photovoltaic (PV) cells using carbon nanotubes, but only by using a layer of polymer to hold the nanotubes in position and collect the electrons knocked loose when they absorb sunlight. But that combination adds extra steps to the production process, and requires extra coatings to prevent degradation with exposure to air. The new all-carbon PV cell appears to be stable in air, Strano says.

The carbon-based cell is most effective at capturing sunlight in the near-infrared region. Because the material is transparent to visible light, such cells could be overlaid on conventional solar cells, creating a tandem device that could harness most of the energy of sunlight. The carbon cells will need refining, Strano and his colleagues say: So far, the early proof-of-concept devices have an energy-conversion efficiency of only about 0.1 percent.

But while the system requires further research and fine-tuning, "we are very much on the path to making very high efficiency near-infrared solar cells," says Rishabh Jain, a graduate student who was lead author of the paper.

Because the new system uses layers of nanoscale materials, producing the cells would require relatively small amounts of highly purified carbon, and the resulting cells would be very lightweight, the team says. "One of the really nice things about carbon nanotubes is that their light absorption is very high, so you don't need a lot of material to absorb a lot of light," Jain says.

Typically, when a new solar-cell material is studied, there are large inefficiencies, which researchers gradually find ways to reduce. In this case, postdoc and co-author Kevin Tvrdy says, some of these sources of inefficiency have already been identified and addressed: For instance, scientists already know that heterogeneous mixtures of carbon nanotubes are much less efficient than homogeneous formulations, and material that contains a mix of single-walled and multiwalled nanotubes are so much less efficient that sometimes they don't work at all, he says.

"It's pretty clear to us the kinds of things that need to happen to increase the efficiency," Jain says. One area the MIT researchers are now exploring is more precise control over the exact shape and thickness of the layers of material they produce, he says.

The team hopes that other researchers will join the search for ways to improve their system, Jain says. "It's very much a model system," he says, "and other groups will help to increase the efficiency."

But Strano points out that since the near-infrared part of the solar spectrum is currently entirely unused by typical solar cells, even a low-efficiency cell that works in that region could be worthwhile as long as its cost is low. "If you could harness even a portion of the near-infrared spectrum, it adds value," he says.

Strano adds that one of the paper's anonymous peer reviewers commented that the achievement of an infrared-absorbing carbon-based photovoltaic cell without polymer layers is the realization of "a dream for the field."

The work also involved MIT graduate students Rachel Howden, Steven Shimizu and Andrew Hilmer; postdoc Thomas McNicholas; and professor of chemical engineering Karen Gleason. It was supported by the Italian company Eni through the MIT Energy Initiative, as well as the National Science Foundation and the Department of Defense through graduate fellowships to Jain and Howden, respectively.

Written by David Chandler, MIT News Office


Japanese Solar Boom? Toshiba Announces 100-MW Solar PV Plant Near Fukushima

Posted: 21 Jun 2012 11:27 PM PDT

Japanese electronics industry giants, power utilities and solar energy companies worldwide have been anticipating the introduction of a renewable energy Feed-in Tariff (FiT) that will subsidize the cost of developing solar, wind, marine, geothermal and other renewable energy resources by allowing providers to pass on costs to consumers. They weren’t disappointed, as the Japanese government’s FiT rates — due to go into effect in July — came in higher than expected, particularly in the case of solar.

Toshiba on Wednesday announced it will invest some 30 billion yen ($373.5 million) in building solar photovoltaic (PV) fields in Minami Soma near Fukushima, the disaster-stricken area on Japan’s northeastern coast. At a rated capacity of 100 MW, Toshiba’s solar PV project surpasses the 70-MW solar project announced by Kyocera, IHI Corp., and Mizuho Corporate Bank as the largest planned installation in the country.

 

One of the advantages of solar PV is that it’s modular, scalable nature. In stark contrast to centralized, mass-market coal, nuclear, and natural gas power plants, solar PV plants can be built and brought on-line incrementally, in stages. Toshiba expects to begin building its 100 MW this year, with first power coming on-line in 2014.

Japan to Retake 1st Place among Solar PV Markets?

The Japanese government recently announced a solar FiT of 42 yen (53 cents) per kWh that power utilities will pay from electricity generated by solar energy. Larger than expected, industry observers are saying the solar FiT will propel Japan past Italy and Germany as the world’s largest market for solar PV.

It’s estimated that Japan’s solar FiT will create a $9.6 billion market. The higher-than-expected solar FiT is intended to boost the amount of electricity produced by solar and other renewable energy resources enough to make up for the closure of Japan’s nuclear power plants, which have been shuttered since the Fukushima disaster.

Nuclear power had accounted for 21% of Japan’s electricity. Shutting the plants down has led to worries, at times fanned in the media, that power shortages were imminent. Japan’s turned to imported fossil fuels to make up the shortfall over the short-term, as well as strong energy efficiency efforts, but it’s looking to broaden and diversify its domestic energy base as quickly as possible to avoid the added costs — economic and environmental — of continued reliance on imported fossil fuels.

No doubt, nuclear and fossil fuel industry participants and advocates will fan public fears and pressure politicians to favor conventional energy resources, but Japan would do right by turning to solar and other clean, renewable energy resource development for long-term sustainability and energy security, as would every nation.


World’s Largest Wind Farm Commissioned

Posted: 21 Jun 2012 03:58 PM PDT

 
Recently, the United Kingdom’s wind industry celebrated the world’s largest offshore wind farm, and switched it on. The Walney wind farm is the name. It comprises 102 turbines and has an electricity generation capacity of 367 MW, enough to provide power for about 320,000 homes.

largest offshore wind farm

The wind project was led by a joint venture between Danish energy giant DONG, UK utility SSE, and investment group OPW.

“DONG Energy is delighted that our record-breaking project is now fully operational, providing clean energy from the UK’s abundant wind resources directly into the grid,” said Benj Sykes, DONG Energy’s director of operations for UK wind power.

“Walney is the first project in the UK to be backed by institutional investors before it was built — a confidence justified by the speed and efficiency of the construction. It shows our commitment to offshore wind development in the UK and to driving down costs.”

 

 

Another sign of progress: DONG energy announced that the project was completed in record-breaking time. All turbines and cables were installed in five and a half months.

Jim Smith, SSE’s managing director for renewables, said the project was “a great example of how much offshore wind has matured as an industry in a relatively short time,” adding that it would now play a role in curbing the UK’s carbon emissions and enhancing its energy security for years to come.

This is an impressively large project. however, it will be quickly surpassed by larger ones, such as the 388-MW West of Duddon Sands project and the whopping 630-MW London Array.

Source: BusinessGreen 
Image Credit: Walney wind farm via Moggy443


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