Showing posts with label solar cells. Show all posts

2012-04-25

Berkeley's Highly Efficient Solar Cells also act like LEDs

New solar cell creates more electricity by lighting up - TECH.BLORGE.com

While solar cell efficiency is theoretically able to reach 33.5 percent efficiency, so far solar cells have only been able to reach 26 percent until now. Eli Yablonovitch, principal researcher and UC Berkeley professor of electrical engineering has developed a new solar cell that will achieve 28.3 percent efficiency and it does so by emitting light.

Source: New solar cell creates more electricity by lighting up - TECH.BLORGE.com

Berkeley Lab Research Sparks Record-Breaking Solar Cell Performances « Berkeley Lab News Center

“A great solar cell also needs to be a great Light Emitting Diode,” says Eli Yablonovitch, the Berkeley Lab electrical engineer who led this research. “This is counter-intuitive. Why should a solar cell be emitting photons? What we demonstrated is that the better a solar cell is at emitting photons, the higher its voltage and the greater the efficiency it can produce.”

Source: Berkeley Lab Research Sparks Record-Breaking Solar Cell Performances « Berkeley Lab News Center

LED-like Solar Cell Absorbs, Emits Light (photonics.com | Apr 2012 | Research & Technology)

Eli Yablonovitch and Owen Miller of UC Berkeley worked out the theory for the new solar cell efficiency. The monitor in the picture illustrates the new physics concept where increased light emission yields higher efficiency. (Image: Eli Yablonovitch)

“Fundamentally, it’s because there’s a thermodynamic link between absorption and emission,” said Owen Miller, a graduate student at UC Berkeley and a member of Yablonovitch’s group.

Designing solar cells to emit light, so that photons do not become “lost” within a cell, has the natural effect of increasing the voltage produced.

“If you have a solar cell that is a good emitter of light, it also makes it produce a higher voltage,” which would increase the amount of electrical energy that can be harvested from the cell for each unit of sunlight, Miller said.

Source: LED-like Solar Cell Absorbs, Emits Light (photonics.com | Apr 2012 | Research & Technology)

KW17 | UC Berkeley unveils LED-type PV cell - SolarServer

Prototype efficiency jumps from 26% to 28.3%

Alta Devices, co-founded by Yablonovitch, used the new concept to create a prototype solar cell made of gallium arsenide (GaAs), a material often used to make solar cells in satellites. The prototype broke the record, jumping from 26% to 28.3% efficiency.

The company achieved this milestone, in part, by designing the cell to allow light to escape as easily as possible from the cell – using techniques that include, for example, increasing the reflectivity of the rear mirror, which sends incoming photons back out through the front of the device.

Source: KW17 | UC Berkeley unveils LED-type PV cell - SolarServer

Related

2011-04-30

WYSIPS Photovoltaic Surface Charges Your Phone Without a Charger

The WYSIPS Company was formed in 2009. It is part of Sunpartner Group’s affiliates. It commercializes WYSIPS’® (What You See Is Photovoltaic Surface) patent.

Technology

WYSIPS technology is the combination of micro lenses with PV cells together on which we apply image stripes and transparent stripes. The lenses concentrate exterior light on the transparent parts to allow the PV cells to capture solar energy. The lenses transform the image for the observer depending on the programmable viewing angles.

The technology is protected by generic international patent. www.wipo.int

Collected from: SunPartner - La Technologie Wysips

WYSIPS Technology does not alter the structure of the surface:

WYSIPS Technology consists of a flexible transparent lenticular film onto which extremely thin photovoltaic strips (in the region of one micron) have been deposited, thereby creating a flexible photovoltaic film which, from some angles, becomes totally transparent. Bonded to an LCD screen, for instance, it transforms the digital image without altering its definition or brilliance.

Collected from: Wysips - what you see is photovoltaic surface

YouTube - 2011 International CTIA WIRELESS: WYSIPS Charges Your Phone Without a Charger

WYSIPS's e-tech entry shows how their technology uses solar energy to charge your phone through a photovoltaic film on top of your phone screen. Watch WYSIPS' President Ludovic Deblois demo of their product.

Collected from: YouTube - 2011 International CTIA WIRELESS: WYSIPS Charges Your Phone Without a Charger

YouTube - Wysips Solar Charging Touchscreen

A first look at a solar charing touchscreen. Imagine being able to charge your phone continuously from the sun or from a nearby light.

Collected from: YouTube - Wysips Solar Charging Touchscreen

Related

2010-07-05

Highly Efficient Solar Cells using Hot Electron Transfer

University of Minnesota researchers clear major hurdle in road to high-efficiency solar cells

MINNEAPOLIS / ST. PAUL (06/17/2010) —A team of University of Minnesota-led researchers has cleared a major hurdle in the drive to build solar cells with potential efficiencies up to twice as high as current levels, which rarely exceed 30 percent.

By showing how energy that is now being lost from semiconductors in solar cells can be captured and transferred to electric circuits, the team has opened a new avenue for solar cell researchers seeking to build cheaper, more efficient solar energy devices. The work is published in this week’s Science.

A system built on the research could also slash the cost of manufacturing solar cells by removing the need to process them at very high temperatures.

Collected from: University of Minnesota researchers clear major hurdle in road to high-efficiency solar cells : UMNews : University of Minnesota

Quantum Dots Could Minimize Energy Loss in Solar Cells

Researchers from the University of Texas in Austin and the University of Minnesota in Minneapolis have discovered that hot electrons can be transferred from quantum dots to an electron acceptor. This process could, theoretically, be used to increase the conversion efficiency of solar cells to 66%.

In typical semiconductor solar cells, photons with energies above the semiconductor’s bandgap generate hot electrons, and much of the energy from the hot electrons is lost through heat before it can be captured and used for electricity.

Using these hot electrons requires slowing down how fast they cool, which quantum dots can do. Then the electrons must be captured and transferred. As detailed in Science, the researchers were able to observe transfer of hot electrons from colloidal lead selenide (PbSe) quantum dots to a titanium dioxide (TiO2) electron acceptor using time-resolved optical second harmonic generation.

Collected from: Solar Novus Today - Quantum Dots Could Minimize Energy Loss in Solar Cells

The University of Texas at Austin- What Starts Here Changes the World

Highly Efficient Solar Cells Could Result from Quantum Dot Research

Dr. Xiaoyang Zhu, professor of chemistry, has discovered a method to capture the higher energy sunlight that is lost as heat in conventional solar cells.

"There are a few steps needed to create what I call this 'ultimate solar cell,'" says Zhu, professor of chemistry and director of the Center for Materials Chemistry. "First, the cooling rate of hot electrons needs to be slowed down. Second, we need to be able to grab those hot electrons and use them quickly before they lose all of their energy."
[...]

Zhu's team has now figured out the next critical step: how to take those electrons out.

They discovered that hot electrons can be transferred from photo-excited lead selenide nanocrystals to an electron conductor made of widely used titanium dioxide.

"If we take the hot electrons out, we can do work with them," says Zhu. "The demonstration of this hot electron transfer establishes that a highly efficient hot carrier solar cell is not just a theoretical concept, but an experimental possibility."

Collected from: Highly Efficient Solar Cells Could Result from Quantum Dot Research | The University of Texas at Austin

XYZ Lab
Center for Materials Chemistry

Electron transfer Photovoltaics Interfacial Science

Photovoltaics: quantum dot interfaces
Semiconductor quantum dots (QDs) are emerging as key materials for light harvesting in next generation photovoltaics. QDs allow tunable optical absorption, solution processability, & potentially high efficiency. We are investigating the extraction of charge carriers from photoexcited QDs. In the example shown here, we use monolayer PbSe QD on TiO2(110) to provide the first experimental evidence of hot electron transfer from QDs to TiO2. Read more in publications 152 (just published in Science.)

Collected from: Welcome to the Zhu research group

Sources

Solar Novus Today - Quantum Dots Could Minimize Energy Loss in Solar Cells
http://www.solarnovus.com/index.php?option=com_content&view=article&id=937:quantum-dots-could-minimize-energy-loss-in-solar-cells&catid=52:applications-tech-research&Itemid=247
University of Minnesota researchers clear major hurdle in road to high-efficiency solar cells : UMNews : University of Minnesota
http://www1.umn.edu/news/news-releases/2010/UR_CONTENT_211711.html
Highly Efficient Solar Cells Could Result from Quantum Dot Research | The University of Texas at Austin
http://www.utexas.edu/news/2010/06/17/quantum_dot_research/
Welcome to the Zhu research group
http://zhu.cm.utexas.edu/index.html

Hot electrons could double solar cell efficiency - tech - 24 June 2010 - New Scientist
http://www.newscientist.com/article/dn19084-hot-electrons-could-double-solar-cell-efficiency.html
Highly efficient solar cells could result from quantum dot research
http://www.sciencedaily.com/releases/2010/06/100617143930.htm
Initiative for Renewable Energy and the Environment | Institute on the Environment | University of Minnesota
http://environment.umn.edu/iree/index.html
News : CEMS : University of Minnesota
http://www.cems.umn.edu/activities/news/index.php?id=265
CEMS : University of Minnesota
http://www.cems.umn.edu/
Welcome to the Zhu research group
http://zhu.cm.utexas.edu/
The Ultimate Solar Cell?
http://www.alternative-energy-news.info/ultimate-solar-cell/
Hot-Electron Transfer from Semiconductor Nanocrystals -- Tisdale et al. 328 (5985): 1543 -- Science
http://www.sciencemag.org/cgi/content/abstract/328/5985/1543

2010-05-09

Solar Cells Printed on Paper

MIT researchers print solar cell on paper

Vladimir Bulovic, director of the Eni-MIT Solar Frontiers Research Center, holds a solar cell printed onto a piece of paper to spell MIT. This is the first paper solar cell, according to MIT and Eni.

Quantum dots

The paper solar cells are one of many avenues being pursued around nanoscale materials at the Eni-MIT Solar Frontiers Center. Layers of these materials could essentially be sprayed using different manufacturing techniques to make a thin-film solar cell on a plastic, paper, or metal foils.

[...]

MIT is focusing much of its effort on quantum dots, or tiny crystals that are only a few nanometers in size. A human hair is about 50,000 to 100,000 nanometers thick.

By using different materials and sizes, researchers can fine-tune the colors of light that quantum dots can absorb, a way of isolating good candidates for quantum dot solar cells.

Collected from: MIT researchers print solar cell on paper | Green Tech - CNET News

Nanoscale layers promise to boost solar cell efficiency

MIT experts are developing novel solar cells that call for multiple layers of nanoscale materials tuned to capture specific wavelengths, or colors, of light. One way they achieve such tuning is by using quantum dots, tiny chunks of material whose absorption color changes with particle size. To prepare the samples shown above, the researchers chemically synthesized colloidal suspensions of quantum dots in inert solvents. By carefully selecting and controlling the quantum-dot size, they produced samples with markedly different colors.

Depositing the nano layers
[...]
Using their novel printing methods, the researchers have created stacked nanostructured PVs. They can layer the nanomaterials on flexible substrates such as rollable plastic or metal foils, or they can deposit them on conventional silicon-based PVs to form “tandem” structures with boosted efficiency. Because of the crystalline nature of silicon, meshing it with other crystalline semiconductors is not easy. Nanomaterials, on the other hand, work fine because they are created in an optically active form before being deposited on the silicon. As a result, the researchers can use simple room-temperature processes, such as printing of nanostructured inks, stamping, or silk screening.

Conversion targets
According to Bulović, first-principles calculations suggest that if they do everything exactly right using a single nanostructured layer on top of silicon, they should achieve 15 percent efficient conversion—somewhat better than today’s commercial PVs. But if they combine multiple layers that are good at absorbing differing parts of the spectrum, theory says that they should get up to 25 percent power conversion.

Collected from: MITEI | Nanoscale layers promise to boost solar cell efficiency

Laboratory of Organic Optics and Electronics is forging the future of Solar Cell Technology and Quantum Dot Lighting using nanotechnology and quantum chemistry expertise

Collected from: MIT EECS - EECS Prof. Vladimir Bulovic and EECS grad students develop Quantum Dot lighting--the light of the future

Sources:

Related:

2009-10-08

Solar shingles

clipped from en.wikipedia.org

Solar shingles

Solar shingles, also called photovoltaic shingles, are photovoltaic cells designed to look like conventional asphalt shingles. There are several varieties of solar shingles, including shingle-sized solid panels that take the place of a number of conventional shingles in a strip, semi-rigid designs containing several silicon solar cells that are sized more like conventional shingles, and newer systems using various thin film solar cell technologies that match conventional shingles both in size and flexibility.

clipped from dvice.com

Dow Powerhouse solar panels look like ordinary rooftop shingles

Dow Solar Solutions figured out a way to make solar panels look just like regular roofing shingles. Dow is launching these Powerhouse Solar Shingles next year, claiming they'll be 30 to 40% cheaper than other solar panels that look like roofing tiles. The company said the shingles will be more than 10% efficient, but cost around 15% less on a per-watt basis.

clipped from www.dailytech.com
Dow Puts Traditional Panels to Shame With New Solar Shingle

The new shingles use a thin film of copper indium gallium diselenide (CIGS) to capture solar energy. As a result, the cells which are encased in molded plastic are relatively flexible, unlike their photovoltaic cousins. And while these elements (such as indium) are quite expensive in bulk, they're used extremely sparingly, keeping costs low.

clipped from www.jetsongreen.com

Dow Unveils Impressive New Powerhouse Solar Shingle (with Photos)

clipped from www.dowsolar.com

Product Overview

What will the benefits of the BIPV Shingle be?

Lower system cost

Improved aesthetics

Easier installation

Long-lasting performance

Sources:

Transparent Flexible Solar Cells

clipped from www.nytimes.com

Solar Tech: Not Just on the Roof Anymore

PHOTOVOLTAIC cells are already a familiar sight on rooftops. But one day, miniature cells may also be found in more unconventional places: power-generating windows, car sunroofs or even awnings.

clipped from www.ecofriend.org

Eco Tech: Semitransparent solar cells to begin a new era of solar electronics

John A. Rogers, a professor of material science and engineering, has developed a new technology which enables solar cells to be printed on many materials, making them flexible and efficient at the same time.

The technology is based on the use of ultrathin, semitransparent cells enabling developers to print cells on plastic rolls that could be unfurled for dozens of uses or stamped onto fabric for energy-generating shirts.

clipped from www.youtube.com

clipped from rogers.mse.uiuc.edu

Rogers Research Group

We seek to understand and exploit interesting characteristics of 'soft'
materials, such as polymers, liquid crystals, and biological tissues as well as hybrid combinations of these materials with unusual classes of inorganics, such as nanoribbons, wires and platelets.

Sources:

Solar Power Textile

Embedding solar cells in textile is a fascinating technological challenge with promising prospects like solar power from clothes, curtains, bags, shelters and more.

Solar Textiles

Clipped from: Solar Textiles: Coming Soon (We Hope) to Clothing Near You : TreeHugger

We think the piezoelectric backpack is a pretty cool concept for generating your own electricity just by walking around, not to mention various other solar bags, but a new development stands to revolutionize the way that we interact with solar power in our everyday lives: solar textiles.

Solar Power Clothing

Clipped from: Smart designed Solar power Clothing - Solar-Tie, University, Carolina, Textile, Apparel, Management, Department, Technology, Digital, Besides - talk2myShirt

A a team at North Carolina State University came up with a brilliant idea how to make use of digital textile printing to incorporate unusual components into a design by printing fabric that matches the pattern of the component.

As an example of how digital textile printing can be used to make the solar panels invisible is the solar jacket and the solar tie.

Clipped from: JTATM - North Carolina State University

APPLICATION OF DIGITAL TEXTILE PRINTING TECHNOLOGY TO INTEGRATE PHOTOVOLTAIC THIN FILM CELLS INTO WEARABLES

[...]
The solar panels were attached using ‘liquid stitch’ adhesive, which eliminated the concern of accounting for a fastener in the design of the digitally printed pattern. The dot of solder used to connect the circuitry to the solar panels was a close color match to the connection bus adhered to the solar panels and was not visually distracting.
[...]
The tie was tested by a user for performance in a typical business environment. The trial consisted of wear during five business days and storage in a closet. During the trials, there were no safety infringements with respect to electrical shock. A visual inspection of the insulated wire revealed no degradation of the insulation after the trials. The wires maintained their ability to conduct electricity without resistance.

Solar Textile

Clipped from: Research — SOEL

Research

Solar energy and energy efficiency

Clipped from: Solar textile — SOEL
Solar textile
We're developing processes to make fiber solar cells that can be woven into textile. [...]

We're developing processes to make fiber solar cells that can be woven into textile.

Textile Based Solar Cells

Clipped from: Toward textile-based solar cells: SPIE Newsroom: SPIE.org

A fiber-based organic photovoltaic may form the building block of cost- effective, energy-harvesting textiles.

The large yellow square represents an area of land that would need to be covered with 10% efficient solar cells to satisfy the national energy demand. In comparison, the arrow points to a small red square whose relative area represents the worldwide area of solar cells currently manufactured and installed. The area of the fabrics image represents the total square meters of textiles imported to the United States. The bottom right image shows the fiber-based organic solar cell, photographed near a penny for size comparison.

Clipped from: Max Shtein — Materials Science and Engineering, University of Michigan

Max Shtein Assistant Professor

Current Nanomaterials Research Projects
[...]
Fiber-Based Organic Solar Cells
[...]

2008-08-25

Large Scale Solar Power Projects

Some big established Japanese companies are putting new efforts in emerging solar power technologies: Mitsubishi Chemical sees opportunity to produce thin film solar cells and Sanyo recently opened an Advanced Development Center to concentrate on developing thin film technology.

Solar Energy Technology

Clipped from: Solar Energy Technologies Program: Thin Films

Thin films of special photovoltaic material can produce solar cells with relatively high conversion efficiencies, while using much less material than crystalline silicon cells. The key materials or technologies that we will discuss are amorphous silicon (a-Si), copper indium diselenide (CIS) and its alloys, and cadmium telluride (CdTe). We also will discuss thin films that use a multijunction design.
[...]
To learn more about PV materials, see:

Crystalline Silicon
Modules

Silicon Cells
Clipped from: Solar Energy Technologies Program: Crystalline Silicon

The solar cell is the basic building block of a photovoltaic system. Individual cells can vary in size from about 1 cm (1/2 inch) to about 10 cm (4 inches) across. This crystalline silicon cell was manufactured by Siemens Solar Industries.
Modules
Clipped from: Solar Energy Technologies Program: Photovoltaic Modules

This PV and wind system contains 8 - 120 watt PV modules that are used for power at a Colorado home

Thin Film Projects

Clipped from: Solar Thin Film Technology Attracts Big Players in Japan | Solar Feeds Solar Thin Film Technology Attracts Big Players in Japan

Thin film solar technology has attracted interest from venture capitalists because of its higher efficiency, lower use of limited silicon, and more easily automated production processes. Now, established Japanese players in the solar arena are getting in the thin film game, followed by companies in China and India, as reported in Renewable Energy World.

Mitsubishi
Clipped from: Mitsubishi Corporation
August 14, 2008
Large-scale Photovoltaic (PV) demonstration project in Brunei Darussalam

Clipped from: Mitsubishi Corporation Announces Large-scale Photovoltaic (PV) Demonstration Project in Brunei Darussalam - MarketWatch

Mitsubishi Corporation Announces Large-scale Photovoltaic (PV) Demonstration Project in Brunei Darussalam

In this demonstration project, a PV system with nominal capacity of 1.2 MW, currently the largest in South-East Asia, will be installed at Seria Power Station in Belait District. With the utilization of this PV system, EDPMO, the Department of Electrical Services and MC will jointly carry out verification tests and evaluations over a period of three (3) years after commissioning. This will be the first installment of a large-scale PV system in Brunei Darussalam.
Clipped from: Brunei Aspires To Be First In The World To Run Purely On Solar Energy - DigitalJournal.com: The Power of Citizen Journalism

SANYO
Clipped from: SANYO Electric Co., Ltd. Global
Clipped from: SANYO -SOLAR ARK-

The Solar Ark, a unique, ark-shaped, solar photovoltaic power generation facility, offers activities to cultivate a better appreciation of solar power generation, and thereby of both ecology and science. This 315m-wide, 37m-tall facility is located in Gifu Prefecture, in the geographical center of Japan, and can be seen from the JR Tokaido bullet train, which runs past on an adjacent railway track.
Stationed at the center of the Solar Ark is the Solar Lab, a museum of solar energy and one of the more unusual museums in the world. A unique, hands-on, outdoor light exhibition will be launched here in 2005, for the first time in Japan. In the future, expect a variety of interesting things to emanate from here.

Clipped from: SANYO to Establish 'Advanced Photovoltaics Development Center' | News Releases | SANYO Electric Co., Ltd. Global

SANYO to Establish 'Advanced Photovoltaics Development Center
In the Gifu Plant-where the Solar Ark stands as a monument and symbol for a clean energy society

Tokyo, December 5, 2007-SANYO Electric Co., Ltd. (SANYO) announced today that it will establish a new 'Advanced Photovoltaics Development Center' within its Gifu Plant in Japan. The plant, located in Anpachi, Gifu prefecture, houses the Solar Ark, a large-scale solar power generation facility that stands as a monument to the world of SANYO's commitment and efforts to create a clean energy-based society.

Pages

2012-04-25

2011-04-30

Technology

2010-07-05

University of Minnesota researchers clear major hurdle in road to high-efficiency solar cells

Highly Efficient Solar Cells Could Result from Quantum Dot Research

XYZ Lab Center for Materials Chemistry

Electron transfer Photovoltaics Interfacial Science

2010-05-09

MIT researchers print solar cell on paper

Nanoscale layers promise to boost solar cell efficiency

Depositing the nano layers

Conversion targets

Laboratory of Organic Optics and Electronics is forging the future of Solar Cell Technology and Quantum Dot Lighting using nanotechnology and quantum chemistry expertise

2009-10-08

Solar shingles

Dow Powerhouse solar panels look like ordinary rooftop shingles

Dow Unveils Impressive New Powerhouse Solar Shingle (with Photos)

Product Overview

What will the benefits of the BIPV Shingle be?

2009-05-02

2008-08-31

Solar Textiles

Solar Power Clothing

Solar Textile

Research

Solar energy and energy efficiency

Solar textile

Textile Based Solar Cells

Current Nanomaterials Research Projects

2008-08-25

Solar Energy Technology

To learn more about PV materials, see:

Silicon Cells

Modules

Thin Film Projects

Mitsubishi

SANYO

XYZ Lab
Center for Materials Chemistry