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"Solar clothe offers moveable power"

"However, the surface area of clothing, at the current level of efficiency, is probably only enough to power tiny sensors, rather than personal electronic equipment.

"We are looking more towards a tent or tarpaulin sized solar panel that can be rolled up and transported easily."He said that improvements in cell efficiency - perhaps offered by the latest crystalline silicon nanotubes - might allow a patch on the back of a jacket, or the side of a bag, to power a laptop or trickle-charge a mobile."I can certainly see this happening in the future."

Cheaper cells

While a breakthrough in this area would potentially produce convenient and moveable solar power, other UK scientists are hunting ways to cut down the cost, so that solar power becomes a more affordable option.Most of the cost comes from the silicon itself, particularly when used in thick, crystalline layers.

Solar cells on the move, powering a coolbox

Dr Alison Walker, a theoretical physicist from the University of Bath, believes that avoiding silicon altogether may be one solution.She is working so-called Grätzel Cells, invented in the 1990s by an Austrian scientist, which use far cheaper titanium dioxide instead.Particles of titanium dioxide are coated with a photosensitive dye, and suspended between two electrodes in a solution containing iodine ions.When this dye is exposed to light energy, some of its electrons jump on to the titanium dioxide particles, which then are attracted to one of the electrodes.

At the same time, the iodine ions transport electrons back from the other electrode to replenish the dye particles.This creates a flow of electrons around the circuit.Researchers say it is only slightly less efficient than a silicon-based cell - and as its principal ingredient is cheap, it represents a potentially affordable technology for developing countries.

“Photovoltaic textiles could positively increase the number of applications available to solar technology

The relatively recent advent of thin-film polymer solar photovoltaics opened up many new uses and new markets for solar energy. The same could be possible through a new partnership aiming for the commercialization of woven, photovoltaic fabrics which could create their own electric energy.

The international collaboration, known as the Photovoltaic Fibers and Textiles Based on Nanotechnology program, is the result of a new partnership between the Massachusetts-based solar upstart Konarka Technologies and Switzerland’s Ecole Polytechnique Fedrale de Lausanne (EPFL). The two expect to yield the first fully integrated woven photovoltaic (PV) material. Such material will allow for tighter integration of power generation capabilities into devices, systems and structures beyond what they say is possible with polymer thin films.

“Photovoltaic textiles could positively increase the number of applications available to solar technology by extending integration to objects made from fabrics, such as garments, tents or coverings,“ said Daniel Patrick McGahn, executive vice president and chief marketing officer, Konarka. “We’ll be able to offer to the marketplace practical new products, such as wearable power generation for mobile electronics made from the solar fabric.“

As part of its ongoing research and development activities, Konarka has already demonstrated it can produce a working PV fiber. To weave a fabric, Konarka and EPFL will optimize the strength, thickness and electrical performance of the PV fiber.
In addition, the team will work to interweave fibers so as to maximize the performance of the textile without compromising the fibers’ integrity. The goal is to produce a fabric sample with at least a four percent efficiency rating. Typical polymer, or plastic-based, thin film PV has an efficiency of approximately 8 percent, solaraccess.com reported.

“This unique solar fabric represents a leap forward for photovoltaic technology,“ said Russell Gaudiana, Konarka’s vice president of research and development. “It will enable power generation capabilities to be woven in rather than applied. For example, we’re able to incorporate our light-activated power plastic onto tenting materials, such as canvas or nylon. Using the fiber, the tent’s base material becomes photovoltaic.“

The consumer market may not exactly be in a hurry to buy PV tents, but the US military just might. The military has taken a recent interest in portable solar PV power as a means to power their increasingly high-tech ground divisions while lowering their needs for a liquid fuel infrastructure.Already numerous contracts have explored the use of PV tents but the approach has been focused largely on the application of thin film sheets over tent and building structures (See Iowa Thin-Films photograph above).
A woven PV tent, however, would represent a completely new direction for this application.

The EPFL team is led by Dr. Jan-Anders Manson, the director of the Laboratory of Composite and Polymer Technology, who is well known for his work as the scientific coordinator for the EPFL-Alinghi Project, which designed the yacht that won the 2003 Americas Cup.The undertaking is expected to last one year and is funded by the Swiss Commission for Technology and Innovation (CTI). CTI promotes the rapid conversion of state-of-the-art laboratory findings to marketable products through cooperation between educational institutions and industry.

This new endeavor further deepens Konarka’s close relationship with the university. In 2002, Konarka became the first company in the United States to license Dr. Michael Gratzel’s dye-sensitized solar cell technology, which augmented its own intellectual property. Since then, Dr. Gratzel has served as a senior scientific advisor to the Company, helping it to commercialize its light-activated plastic power.

Konarka’s new partnership aims to develop woven PV material for such uses as military PV tents. Here, a tent from Iowa Thin Films includes strips of thin film PV applied to the top. Konarka’s approach would allow the fabric iteself to generate power.

SYDNEY, Australia -- Fancy this: clothing that generates solar power,

By Stewart Taggart Stewart Taggart | Also by this reporter
02:00 AM Mar, 18, 2002 EST

SYDNEY, Australia -- Fancy this: clothing that generates solar power,
fabrics that beep if you risk athletic injury and bed sheets that monitor your heartbeat and physiological health.Welcome to the world of "intelligent polymers," a chemical research frontier that could revolutionize textiles.

At its simplest, intelligent polymers are plastic strands that can carry electricity, altering their conductivity in response to stretching, heating or sunlight. By weaving these into clothing, and measuring changes in the current passing through them, any number of new applications are possible.

The groundbreaking research in this area occurred back in the 1970s when U.S. and Japanese researchers stumbled across the discovery that, in certain circumstances, plastic could act as a conductor, rather than an insulator, of electricity. But it's only been in the past five years that researchers have looked aggressively at incorporating these polymers into things such as clothing.

The first prototype thus far has been the "knee sleeve," a training device tested last year on Australian professional athletes to reduce knee injuries. It fits over the knee like an open-ended sock.When the fabric is stretched, indicating a harmful movement of the knee, the altered electrical charge within the sleeve's polymers triggers a detachable buzzer. That tells the athlete he's got bad habits and risks anterior cruciate ligament (ACL) damage, according to Julie Steele, a biomechanics researcher at the University of Wollongong, where the device was designed.

Nearly 70 percent of such injuries come from landing the wrong way from jumps. They can sideline athletes in sports such as basketball, football and rugby for a year or longer and cost millions of dollars to treat, Steele said.