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Dye solar cell

Dye Solar Cell Industrialisation Conference
Dye Solar Cell Industrialisation Conference

Date: Tuesday, Sept 11 - Thursday, Sept 13, 2007
Venue: Olma Messen St.Gallen

The 3rd Generation Photovoltaics

The second International Conference on Industriali-sation of Dye Solar Cells is integrated with NanoEurope. The conference is once again sponsored by Dyesol Ltd, joint Platinum sponsor of NanoEurope 2007.

This conference brings together developers, industrial organisations, and government research organi-sations working on the challenges to introduce DSC into the broad solar power community. While the conference does not stress academic research it does include session on modelling and next generation DSC devices and designs (such as tandem devices).

The key features of the conference highlight:

Advances in long term performance
Module designs
Applications demonstrations
Module performance in real life conditions
Reliability proving
Cost reduction of materials
Manufacturing processes and equipment
Automation of manufacture
High volume manufacturing requirements
The conference will be a significant advantage to investors to obtain real data on DSC. Product designers and architects will gain insight into the reactive merits of DSC compared to classical photovoltaics. Researchers will gain understanding of the key industrial criteria to enable better direction of R&D. Students will benefit from an overview of all aspects of DSC.

Conference language: English
The entire program will be available in may 2007.

Organizers: DYESOL (www.dyesol.com) & NanoEurope

Olma Messen St.Gallen
Spluegenstrasse 12, CH-9008 St.Gallen, Switzerland
Phone: +41 071 242 04 44 Fax: +41 071 242 02 32
Email: info@nanoeurope.com
Posted by Kuppuswamy Kalyanasundaram at 8:17
DYESIK strikes deal to acquire control of GREATCELL SOLAR SA

Media Release (2 pages) ? 2nd October 2006

Acquisition of most of the equity in Swiss-based Greatcell Solar SA will reinforce
Dyesol?s IP portfolio and continue to build the strategic position Dyesol holds in
Europe and with EPFL.

The Board of Dyesol Ltd has approved in principle the option to acquire a majority
shareholding in the Swiss-based Greatcell Solar SA. Dyesol Ltd had, prior to
listing on the ASX, entered into an option deed to acquire the shareholding of
Gavin Tulloch and Tulloch Management Pty Ltd, representing approximately 51%
of the issued capital of the Swiss-based company Greatcell Solar SA (Greatcell).

This acquisition, which will be carried out by Dyesol?s wholly owned subsidiary,
Sustainable Technologies International Pty Ltd (STI), was conditional on due
diligence to be undertaken by Dyesol. In undertaking due diligence, the Board of
Dyesol concluded that it would be in the best interests of the Company and
shareholders to also acquire the second largest shareholding, enabling Dyesol
to move to approximately 99% control of Greatcell. The remaining 1% of shares would
be retained by three other shareholders to satisfy corporate shareholding
requirements in Switzerland.

The Company has reached an in-principle agreement with Greatcell?s second largest
shareholder for STI to acquire his holding of approximately 48% of the issued
capital of Greatcell, for a total consideration of 500,000 fully paid ordinary
shares in Dyesol Ltd, to be issued in two tranches, with each share issue subject
to agreed escrow periods. This transaction, when concluded, will result in less
than 1% dilution of existing shareholders. Both transactions are subject to all
necessary consents being obtained, and all regulatory requirements within
Australia and Switzerland being satisfied, prior to conclusion of the
transaction and issue of shares.

On conclusion of these transactions, Dyesol will have a presence in its own
right in Europe. The Greatcell operation is located in Lausanne, close to Ecole
Polytechnique Fédérale de Lausanne (EPFL), and Greatcell has enjoyed a rewarding
and collaborative relationship with EPFL over a number of years. It is Dyesol?s
intention to continue and expand this relationship. Greatcell has complementary
IP to the Dyesol IP portfolio and has expertise in the manufacture of specialised dyes currently used by Dyesol. Over the years, Greatcell has been involved in a
number of Collaborative European Community (EC) R&D programs associated with Dye
Solar Technology and materials development that have led to independent and
potentially valuable IP. This transaction is another step in Dyesol?s move to
become the leading player in Dye Solar Technology.

Further information: Mrs Sylvia Tulloch (Managing Director Dyesol) DyesolNews@dyesol.com
Posted by Kuppuswamy Kalyanasundaram at 15:16
Wales to host first Dye Sensitized Solar Cell plant
October 18, 2006

John Walko / EE Times Europe

LONDON ? A recently established renewable energy company, G24 Innovations Ltd, is planning to build the first plant to make dye sensitized solar cells (DSSC) on a commercial scale at a facility in Cardiff, Wales . The eventual investment into producing the so called 'solar foils' could be between £60 million and £75 million and the project could create 300 jobs.

"We have the funds for the first phase of the project, which is to do a pilot plant and line capable of a capacity of about 25 Megawatts as well as install a coater. That would be an investment of about £20 million and be ready by early next year. The second phase would be substantially more ambitious and have a capacity of up to 200 Megawatts, and this would be ready by 2008," Paul Turney, CEO of G24 Innovations told EE Times Europe .

Turney said that while the project has "strong support" from the Welsh Assembly Government and local agencies, "we have not sought any financial assistance or grants as we need to move forward quickly and that may have held us back a little." He added the first phase is already on track and producing pilot quantities of the foils.

The technology for making the dye-sensitized solar cells come from a licensing deal with Konarka Technologies Inc (Lowell, Mass.), a specialist in photovoltaic technologies, and Ecole Polytechnique Federale de Lausanne. The original invention of the DSSC was done at the EPFL by Professor Michael Graetzel and his team in the late 1980s, and the technology has subsequently been enhanced by engineers at Konarka.

Much of the laminating machinery for the facility will come from Solarcoating Machinery GmbH (Dormagen, Germany), a spin off from Coatema Coating Machinery GmbH.

G24 Innovations' main backer is Renewable Capital, an investment and incubator firm specializing in green energy projects with headquarters Delaware, with minority shareholdings from EPFL, Konarka Technologies and Solarcoating.

DSSC is said to use a wider range of light spectrum than conventional solar cells, and thus generate power from all visible light sources and at relatively low levels of light intensity. The photovoltaic material produces energy through a process that Turney likens to photosynthesis in plants.

The DSSC modules are manufactured by printing a thin layer of titanium dioxide on to a layer of film and then, through the use of nanotechnology, further manipulating the film's atoms and molecules so as to generate electricity.

The process involves 'roll-to-roll' equipment similar to that used to make textiles and photographic films which is said to reduce costs dramatically compared with that for making traditional solar cells.

"Unlike traditional solar cells, we do not use silicon or heavy metals and the resulting material is perhaps a fiftieth the weight of normal solar cells," said Turney.

He added: "With the tremendous global explosion in the use of mobile electronic devices, there is a huge untapped market for our ground breaking technology."

Initial target markets for the DSSC include mobile phone chargers, especially for developing countries, and as a power source for consumer products such as MP3 players, laptops and handheld game consoles. The company will also target applications such as smart textiles and as the basis for novel building-integrated products that could provide the energy source for a part of a building.
Posted by Kuppuswamy Kalyanasundaram at 15:08
MIT Technology Review interview with Prof. M. Graetzel
Solar Cells for Cheap

Not everyone gets a solar cell named after them: but Michael Gratzel did. He says his novel technology, which promises electricity-generating windows and low manufacturing costs, is ready for the market.

By Kevin Bullis
Tuesday, September 12, 2006

Source: MIT Technologyreview.com

Michael Grätzel , chemistry professor at the Ecoles Polytechniques Fédérale de Lausanne in Switzerland, is most famous for inventing a new type of solar cell that could cost much less than conventional photovoltaics. Now, 15 years after the first prototypes, what he calls the dye-sensitized cell (and everyone else calls the Grätzel cell) is in limited production by Konarka, a company based in Lowell, MA, and will soon be more widely available.

Grätzel is now working on taking advantage of the ability of nanocrystals to dramatically increase the efficiency of solar cells.

Technology Review asked him about the challenges to making cheap solar cells, and why new technologies like his, which take much less energy to manufacture than conventional solar cells, are so important.

Technology Review: Why has it been so difficult to make efficient, yet inexpensive solar cells that could compete with fossil fuels as sources of electricity?

Michael Grätzel: It's perhaps just the way things evolved. Silicon cells were first made for [outer] space, and there was a lot of money available so the technology that was first developed was an expensive technology. The cell we have been developing on the other hand is closer to photosynthesis.

TR: What is its similarity to photosynthesis?

MG: That has to do with the absorption of light. Light generates electrons and positive carriers and they have to be transported. In a semiconductor silicon cell, silicon material absorbs light, but it also conducts the negative and positive charge carriers. An electric field has to be there to separate those charges. All of this has to be done by one material--silicon has to perform at least three functions. To do that, you need very pure materials, and that brings the price up.

On the other hand, the dye cell uses a molecule to absorb light. It's like chlorophyll in photosynthesis, a molecule that absorbs light. But the chlorophyll's not involved in charge transport. It just absorbs light and generates a charge, and then those charges are conducted by some well-established mechanisms. That's exactly what our system does.

The real breakthrough came with the nanoscopic particles. You have hundreds of particles stacked on top of each other in our light harvesting system.

TR: So we have a stack of nanosized particles...

MG: ...covered with dye.

TR: The dye absorbs the light, and the electron is transferred to the nanoparticles?

MG: Yes.

TR: The image of solar cells is changing. They used to be ugly boxes added to roofs as an afterthought. But now we are starting to see more attractive packaging, and even solar shingles (see "Beyond the Solar Panel"). Will dye-sensitized cells contribute to this evolution?

MG: Actually, that's one of our main advantages. It's a commonly accepted fact that the photovoltaic community thinks that the "building integrated" photovoltaics, that's where we have to go. Putting, as you say, those "ugly" scaffolds on the roof--this is not going to be appealing, and it's also expensive. That support structure costs a lot of money in addition to the cells, and so it's absolutely essential to make cells that are an integral part.

[With our cells] the normal configuration has glass on both sides, and can be made to look like a colored glass. This could be used as a power-producing window or skylights or building facades. The wall or window itself is photovoltaicly active.

TR: The cells can also be made on a flexible foil. Could we see them on tents, or built into clothing to charge iPods?

MG: Absolutely. Konarka has a program with the military to have cells built into uniforms. You can imagine why. The soldier has so much electrical gear and so they want to boost their batteries. Batteries are a huge problem--the weight--and batteries cost a huge amount of money.

Konarka has just announced a 20-megawatt facility for a foil-backed, dye-sensitized solar cell. This would still be for roofs. But there is a military application for tents, and Konarka is participating in that program.

TR: When are we going to be able to buy your cells?

MG: I expect in the next couple of years. The production equipment is already there. Konarka has a production line that can make up to one megawatt [of photovoltaic capacity per year].

TR: How does the efficiency of these production cells compare with conventional silicon?

MG: With regard to the dye-cells, silicon has a much higher efficiency; it's about twice [as much]. But when it comes to real pickup of solar power, our cell has two advantages: it picks up [light] earlier in the morning and later in the evening. And also the temperature effect isn't there--our cell is as efficient at 65 degrees [Celsius] as it is at 25 degrees, and silicon loses about 20 percent, at least.

If you put all of this together, silicon still has an advantage, but maybe a 20 or 30 percent advantage, not a factor of two.

TR: The main advantage of your cells is cost?

MG: A factor of 4 or 5 [lower cost than silicon] is realistic. If it's building integrated, you get additional advantages because, say you have glass, and replace it [with our cells], you would have had the glass cost anyway.

TR: How close is that to being competitive with electricity from fossil fuels?

MG: People say you should be down to 50 cents per peak watt. Our cost could be a little bit less than one dollar manufactured in China. But it depends on where you put your solar cells. If you put them in regions where you have a lot of sunshine, then the equation becomes different: you get faster payback.

TR: Silicon cells have a head-start ramping up production levels. This continues to raise the bar for new technologies, which don't yet have economies of scale. Can a brand-new type of cell catch up to silicon?

MG: A very reputable journal [Photon Consulting] just published predictions for module prices for silicon for the next 10 years, and they go up the first few years. In 10 years, they still will be above three dollars, and that's not competitive.

Yes, people are trying to make silicon in a different way, but there's another issue: energy payback. It takes a lot of energy to make silicon out of sand, because sand is very stable. If you want to sustain growth at 40-50 percent, and it takes four or five years to pay all of the energy back [from the solar cells], then all of the energy the silicon cells produce, and more, will be used to fuel the growth.

And mankind doesn't gain anything. Actually, there's a negative balance. If the technology needs a long payback, then it will deplete the world of energy resources. Unless you can bring that payback time down to where it is with dye-cells and thin-film cells, then you cannot sustain that big growth. And if you cannot sustain that growth, then the whole technology cannot make a contribution.

TR: Why does producing your technology require less energy?

MG: The silicon people need to make silicon out of silicon oxide. We use an oxide that is already existing: titanium oxide. We don't need to make titanium out of titanium oxide.

TR: An exciting area of basic research now is using nanocrystals, also called quantum dots, to help get past theoretical limits to solar-cell efficiency. Can dye-sensitized cells play a role in the development of this approach?

MG: When you go to quantum dots, you get a chance to actually harvest several electrons with one photon. So how do you collect those? The quantum dots could be used instead of a [dye] sensitizer in solar cells. When you put those on the titanium dioxide support, the quantum dot transfers an electron very rapidly. And we have shown that to happen.

TR: You are campaigning for increased solar-cell research funding, and not just for Grätzel cells.

MG: There's room for everybody.

I am excited that the United States is taking a genuine interest in solar right now, after the complete neglect for 20 years. The Carter administration supported solar, but then during the Reagan administration, it all dropped down by a factor of 10. And labs like NREL [National Renewable Energy Laboratory in Golden, CO] had a hard time surviving. But I think there is going to be more funding.
Posted by Kuppuswamy Kalyanasundaram at 8:05
Press reports: Newswire today /March 2006
Nanowires Could Lead to Improved Solar Cells

Honolulu, HI, United States, 03/06/2006

With an increased focus on alternative sources of cheap, abundant, clean energy,
solar cells are receiving lots of attention. Researchers are now on the brink of improving
the efficiency of solar cells through nanowires.

The dye sensitized solar cell (DSSC) is one of the most important developments in
photovoltaics in the last two decades. Excitonic solar cells, such as organic, hybrid organic
and inorganic solar cells are promising devices for inexpensive, large-scale solar energy
conversion. DSSCs are an exciting variant of the most efficient and stable of the excitonic
photovoltaic devices.

Untreated TiO2 absorbs light only in the UV region, but when the surface becomes modified
with dye molecules, these can absorb light in the visible range and then transfer the excited
electron to the particle. Back in 1991, Graetzel et. al came up with the methodology to
dye-sensitize colloidal TiO2 film as a way to fabricate low-cost, high-efficiency solar cells

Central to today's DSSCs is a thick titanium dioxide (TiO2) nanoparticle film that provides
a large surface area for the adsorption of light-harvesting molecules. One drawback of
nanoparticle DSSCs is their reliance on trap-limited diffusion for electron transport, a slow
mechanism that can limit device efficiency, especially at longer wavelengths.

To improve electron transport in these solar cells, while maintaining the high surface area
needed for dye adsorption, two researchers have designed alternate semiconductor
morphologies, such as arrays of nanowires and a combination of nanowires and nanoparticles,
to provide a direct path to the electrode via the semiconductor conduction band. Such
structures, that increases the rate of electron transport, may provide a means to improve
the quantum efficiency of DSSCs in the red region of the spectrum, where their performance
is currently limited.

The paper is titled "Dye-sensitized solar cells based on semiconductor morphologies with
ZnO nanowires" and will be published in the March 23, 2006 edition of Solar Energy
Materials and Solar Cells. Professor Eray Aydil from the University of Minnesota, co-author
of the paper together with Jason Baxter from the UC Santa Barbara, explained to Nanowerk:

"Detailed research into the way DSSCs work has shown that transport and recombination
of electrons in the nanoparticle TiO2 network are coupled. Researchers from NREL have
shown that this interdependency may be due to transport limited recombination; that
is any increase in transport rates also result in an increase in the recombination rate
with no net change in the cell performance."

"However, the use of single crystal nanowires may allow electron transport via extended
states in the conduction band rather than by a series of hops between trap states" says
Aydil. Thus the interdependency between the transport and recombination may be
removed in the case of nanowire DSSCs.

In addition, if nanowires achieve electron transport rates that are significantly faster
than transport rates in nanoparticle films, significant flexibility in choosing the hole-transport
medium could be gained since faster recombination rates could be tolerated. "One could
also make thicker films and increase optical density in the regions of the solar spectrum
where the dye absorption decreases" says Aydil. "These possibilities are the driving force
behind pursuing nanowire-based dye sensitized solar cells."

By Michael Berger, Copyright 2006 Nanowerk LLC

Posted by Kuppuswamy Kalyanasundaram at 11:00
DSSC is in the list of Emerging Research Fronts
Emerging Research Fronts

From the database of "Essential Science Indicators", ESI Thompson has compiled
a list of, Emerging Research Fronts and
by a comparison of the data sets for the current period of May 2000-April 30, 2006,
and the previous period of March 2000-February 28, 2006 (sliding 6-year period).

ESI Special Topics is an editorial component of Essential Science Indicators

Dye sensitized solar cell appears in this list of August 2006, see

Posted by Kuppuswamy Kalyanasundaram at 10:54
Press reports: Green Car Congress
Aisin Seiki and Toyota Developing Dye-Sensitized Solar Cells for Cars and Homes

16 May 2006

Aisin Seiki, perhaps better known as a transmission manufacturer, has worked with
Toyota Central R&D Labs Inc. to develop dye-sensitized solar cells (DSC)?photoelectro-
chemical cells also known as Graetzel cells.

Because dye-sensitized solar cells are made of low-cost material and do not require an
elaborate apparatus for manufacture, they are around 60% cheaper to make than
conventional silicon-based products.

In addition to being less costly, DSCs can generate electricity in even weak light. Moreover,
since the solar cells can be adjusted in terms of both transparency and color, they can be
designed for attachment to windows in cars and homes, or given a mirror-like reflective
surface as well as patterned with marbling.

Toyota and Aisin Seiki earlier developed two prototype of DSC modules to meet different
artistic and architectural designs, which the companies displayed during the Aichi
EXPO 2005.

Aisin Seiki reportedly is now evaluating the durability and heat characteristics of the
solar cell with the goal of having a practical version ready in four to five years for
applications in cars and homes, according to the Nihon Keizai Shimbun.

Honda Motor is also entering the market for solar cells designed for use in households
and vehicles. The company is building a ¥10-billion (US$86.5-million) factory to begin
mass production in fiscal 2007 of solar cells made an inexpensive thin-membrane
non-silicon metal compound developed by Honda engineering.

The Honda solar panels, first announced in 2002, feature a light-absorbing layer formed
by a compound made of copper, indium, gallium and diselenium (CIGS). Other companies
working with CIGS cells include Shell Solar and Würth.

Posted by Kuppuswamy Kalyanasundaram at 10:48
Press reports: ABC Australia Science News
Green leaves inspire solar cells

Anna Salleh /ABC Science Online)
Monday, 4 September 2006

Synthetic molecules that mimic chlorophyll in plants may one day form the basis
of highly efficient solar cells, say Australian researchers. Professor Max Crossley's molecular
electronics group at the University of Sydney recently presented its research at the
International Conference on Porphyrins and Phthalocyanines in Rome.

"Nature has evolved this very efficient process, over millions of years, for harvesting
light and then converting it into energy," says Crossley. "We're trying to mimic aspects of
natural photosynthesis." Dense arrays of chlorophyll molecules in leaves are responsible
for converting light energy to electrical energy and then to chemical energy.

Critical to this function of chlorophyll is the pigment porphyrin, which is attached to a
central magnesium ion. Crossley and team have made a synthetic form of chlorophyll that
performs the first part of that process, converting light energy to electrical energy.

As in nature, when a large number of these synthetic molecules are arranged in a
dense array they act in concert to efficiently collect photons of light. "There has to be
a lot of them because if there was only one it would be a very inefficient process,"
says Crossley.

for full details see;
Posted by Kuppuswamy Kalyanasundaram at 10:22
Press reports: Nanotechnology News
World's First Rechargeable Long-Life Solar Cell

31st August 2005

Solaris Nanosciences has demonstrated a completely rechargeable dye sensitized
solar cell (DSSC or Graetzel Cell) creating the lowest manufacturing cost, long-life
photovoltaic system in the world. DSSCs which are based on low cost materials
and simple construction, have to date suffered from limited operating lifetimes due
to the degradation of the sensitizer dyes.

Solaris' nontoxic chemical process allows the degraded dye in already installed DSSCs
to be removed and replaced with new dye, restoring the performance of the original
solar cell. "This low cost process, which can be performed by the existing base of heating
and air conditioning businesses, requires less than thirty minutes and takes the operating
life of these photovoltaics (PV) beyond that of silicon to over 30 years," said
Nabil M. Lawandy, CEO of Solaris Nanosciences. Lawandy also stated, "Not only can
we replace the original dye, but we have shown that newer, more efficient dyes,
resulting from ongoing efforts worldwide, can be used in recharging. This effectively
allows for efficiency upgrades over the life of the installed system."

The recharging process and its performance were independently confirmed at the
Swiss Federal Institute of Technology Lausanne where DSSCs were invented by
Professor Michael Graetzel.

Solaris plans to develop a large scale prototype of its rechargeable solar cell for testing
at the National Renewable Energy Laboratory (NREL) and with corporate partners to
explore the distribution of this new PV technology through the building and construction

for details see
Posted by Kuppuswamy Kalyanasundaram at 10:11
Conf. on Plastics Electronics
2nd International Plastics Electronics Conference
October 24 & 25, 2006
Sheraton Hotel & Conference Center, Frankfurt airport

The 2nd Plastic Electronics Conference & Showcase offers scientists, researchers
engineers, developers and business executives an international forum to discuss
the latest achievements in research, development and manufacturing of
market-oriented applications in organic electronics.

Parallel symposium Photovoltaics October 24, 2006
Chairman and moderator: Dr. Christoph Brabec (Chief Technology Officer
Konarka Austria R&D FmbH, Linz, Austria)

Future concepts and technologies for high performance dye sensitized
photovoltaic technologies
paper by Dr. Jan Kroon (Programme Manager Organic thin film PV
ECN Energy Research Centre of the Netherlands, Petten, Netherlands)

High performance materials for organic/hybrid dye sensitized photovoltaics
paper by Prof. Dr. Shuji Hayase (Dept of Biological Functions & Engineering,
Graduate Schoolof Life Science & System Engineering Kyushu Institute of Technology,
Fukuoka, Japan)

conf site:

Prof. Michael Graetzel serves as the Chairman of the Scientific Advisory Board
for the "The Plastic Electronics Foundation".
Posted by Kuppuswamy Kalyanasundaram at 10:08
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