By adding gold nanoparticles to organic photovoltaic panels, a research team from UCLA, China, and Japan have increased the solar efficiency. By using the plasmonic effect, where the metal helps absorb more sunlight, the team pushed the overall light to energy output efficiently from 5.22 to 6.24, for a 20% increase. The construction places a gold layer between two light absorbing subcells, called a tandem polymer solar cell. Their method of layering has sidestepped all past difficulties of adding metal nanostructures into devices.

The success of the plasmonic effect of gold nanoparticles will lead to future development of polymer solar cells. The interlayer structure is being considered for other materials and "opening up opportunities" for higher efficiency, milt-stack, tandem solar cells. However, with gold currently at $1,800 USD per oz, the gains in efficiency may be diminished by manufacturing costs.

The project lead is professor Yang Yang of UCLA's Henry Samueli School of Engineering and Applied Science and director of the Nano Renewable Energy Center at UCLA's California NanoSystems Institute. The research team includes Xing Wang Zhang from the Key Lab of Semiconductor Materials Science at the Institute of Semiconductors at Beijing's Chinese Academy of Science and Ziruo Hong from the Graduate School of Science and Engineering at Japan's Yamagata University.

Three people, alone, changed organic solar cells forever.

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Starting out as a joke about a beer chilling bikini, Andrew Schneider from New York University has created a solar power bikini that actually works. A melding of textile work and electrical engineering, 1" x 4" photovoltaic thin film solar cells have been sewn together with conductive thread. The power is then funneled through a 5V regulator and terminated into a standard female USB port. A thin connector bridges between the top and bottom of the suit to collect all power to one source. The overall power output is enough to charge a single MP3 player or cell phone, mostly due to the fact that overall surface area is rather skimpy. Although geared towards education, the Solar Bikini is currently being sold through the Solar Coterie website. Each one is custom, only $200 USD , so act fast.

Keep in mind, the number one issue with solar cells, even with thin film, is the buildup of heat in the cells themselves. Also, with the conductive thread, this suit can not get wet at all. So, no swimming or sweating allowed.

To actually deliver his original joke of cooling a beer, a male version of the solar suit will be made into a pair of board-shorts. The solar collector, with more surface area, will be able to charge a device as well as power a Peltier cooling device for chilling one drink.

Will these ever be able to enter the water? Schneider is hard are work to make it happen.

Eavesdropper

Pictures via Andrew Schneider

A recent research project wants British soldiers to wear solar photovoltaic cells and a thermoelectric system to harness light or heat for 24/7 power. The goal is to lighten the packs soldiers carry by 50% and reduce the number of return trips to the base for recharging. An added benefit of the system is that after the various sources absorb all the energy across the electromagnetic spectrum, the soldiers will appear less obvious to infra-red surveillance equipment.

This project is a collaboration between the University of Glasgow and Strathclyde, Leeds, Reading, Loughborough, and Brunel Universities. Funding support is also coming from The Defense Science and Technology Laboratory (DSTL) and the Engineering and Physical Sciences Research Council (EPSRC). Many different disciplines are at work on this project, including chemists, material science, process, electrical, and design engineers. As you can see, everyone is quite serious about this endeavor.

Solar PV will harness light in the day, and thermoelectric devices will take over the same task at night. "Advanced" storage schemes will be used to store excess energy while still providing continuous power. Side note; the thermal harvesters should run 100% of the time. Daytime heat and the active soldier will generate much more power than in the evening, but the team will discover this soon.

Professor Ducan Gregory of Glasgow said they are planning to have a prototype within 2 years. He hopes the technology will filter into other categories, like medical transportation, satellites, or other space applications.

Good luck, see you all in 2 years.

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Two years after the hurricane Katrina disaster in New Orleans, Louisiana, Brad Pitt toured the area and noticed most of the 4000 homes that were destroyed were not fixed, and the area abandoned. He promised the families he met there that he would "Make It Right." Like many, Pitt was let down by the lack of governmental help in the wake of the disaster. After meeting with local community groups and families Pitt established the "Make It Right Foundation," a non-profit organization set to build 150 green, affordable, high-quality homes that were closest to the levee breach, the lower 9th ward.

Bill Clinton and Brad Pitt at the ground breaking in 2008

Make It Right broke ground in 2008, and since then have completed 70 homes. 21 local, national, and international architects designed the new homes, and donated the plans to the project. The designs have many green attributes. The homes feature a 2.7 to 3.0 kilowatt solar PV system, low-VOC paints, carpets, and other finishes, and recycled materials are used throughout. Metal roofs are used to reduce heat gain, it is hot down there, and capture rain water. Some feature green roofs. All internal materials are certified by Forest Stewardship. The homes have tankless waterheaters, Energy Star Rated appliances and light fixtures. The windows and doors have "low-e" coatings, to help reduce heat flow into the home.

2 of the finished homes. They look amazing.

Other interesting features include kevlar reinforced windows, advanced framing and engineered wall sections, all to withstand up to 130mph hurricane winds. And all the homes are built 6 to 8 feet off the ground to help in case of another flood.

Brad Pitt and Microsoft's Bing have pledged, together, $10 million dollars in matching funds for the project. For more information and links to donate, go to the Make It Right webpage.

I just found out about this program, and I am definitely going to donate.

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Nippon Telegraph and Telephone Copt (NTT), Toyko Japan, combines photovoltaic and thermal harvesting in the same container with an added benefit of up to 50% increase of current output. Sanyo Semiconductor Co's silicon PV cells are housed in a water-tight, transparent, enclosure in a staggered stair like configuration. This setup can provide power normally. However NTT fills the container with water, the water then refracts and reflects the light in such a way that the PV cells current output increases up to 50%. The PV cells absorb the visible light, while the water inside absorbs the infrared. The water is then heated and can be pumped out to be used.

The water has a similar effect like the "FUSION" film I wrote about in another post, but seems to have a greater effect. The film is cheap, while the NTT water enclosure is not. So, for now the water option will remain in the research lab. My question is, how deep does the water have to be to provide that effect?

I hope to see more from NTT.

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HyperSolar, has made a breakthrough in magnification of light on their solar panels, resulting in an increase in solar energy output. They plan to take the 1 cm thick solar product and place then right on top of existing, and aging, flat solar panels. The purposed increase of light magnification, 400%, reduces the number of solar cells inside of a panel which in turn reduces the cost. Though, I would wager that people would want to put the HyperSolar panels next to existing one. Even the smaller amount of energy from the old equipment is a little bit more you could harvest.

Tim Young, CEO of hyper solar, touts the new product, "Unlike current concentrated photovoltaic solutions that require bulky mirrors or lenses and sun tracking mechanisms, the HyperSolar concentrator will be a thin and flat self-tracking solar concentrator that conventional solar manufacturers can use in conventional flat solar panels. A HyperSolar concentrator is a concentrator like no other with a multi-billion square feet opportunity. Every square foot of solar panel demand is an opportunity to reduce the number of expensive solar cells by incorporating a square foot of HyperSolar."

See more at their site.

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EDF Group and Solaris Synergy have developed a new solar system that floats on existing bodies of water. Geared towards usage in constructed pools used for industrial or agricultural purposes. The panels are capable of producing 200kW each. These panels will be inexpensive silicon cells. But wait, these overheat right? Not an issue. As an added benefit they are cooled by the water they are floating in, which in turn make the panels more efficient. Also, the panels allow oxygen to pass through easily. This is to keep the water from stagnating. The companies have presented prototypes at the 4th International Eilat-Eilot Renewable Energy Conference. A 9 month test will be conducted at a hydro-electric plant in southern France later this year.

Zero

Solar cells are a key technology in the drive toward cleaner energy production. Unfortunately, solar technology is not yet economically competitive and the cost of solar cells needs to be brought down. One way to overcome this problem is to reduce the amount of expensive semiconductor material used, but thin-film solar cells tend to have lower performance compared with conventional solar cells. Yuriy Akimov and Wee Shing Koh at the A*STAR Institute of High Performance Computing (Singapore) have now improved the light conversion efficiency of thin-film solar-cells by depositing aluminum particles on the cell surface. Metallic nanoparticles can direct light better into the solar cell and prevent light from escaping. In conventional ‘thick-film’ solar cells, the nanoparticles would have little effect because all the light is absorbed by the film due to its thickness. For thin films, however, the nanoparticles can make a big difference. Their scattering increases the duration the light stays in the film, bringing the total absorption of light up to a level comparable with that for conventional solar-cells. The researchers modeled the light absorption efficiency of solar cells for various nanoparticle materials and sizes. In particular, they compared the properties of silver versus aluminum nanoparticles. In most studies on the subject, silver particles have been preferred. These have optical resonances in the visible part of the spectrum that are even better at focusing the light into the solar cell. Unfortunately, there is a tradeoff: the optical resonances also cause the absorption of light by the nanoparticles, which means the solar cell is less efficient. In the case of silver, this resonance is right in the key part of the solar spectrum, so that light absorption is considerable. But not so for aluminum nanoparticles, where these resonances are outside the important part of the solar spectrum. Furthermore, the aluminum particles handle oxidation well and their properties change little with variations in shape and size. And more importantly, their scattering properties are robust in comparison with silver nanoparticles.

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