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University of southern California experts suggest us a more powerful use of graphene photovoltaics

Can you imagine people powering their cellphone or music/video device while jogging in the sun?

A University of Southern California team has produced flexible transparent carbon atom films that may have great potential for a brand new breed of solar cells.

Inside a paper recently published by the journal ACS Nano, researchers stated that organic photovoltaic (OPV) cells have been proposed as a method to obtain cost effective energy due to their ease of manufacture, light weight, and compatibility with flexible substrates.

The new work suggests that graphene, a highly conductive and highly transparent type of carbon made up of atoms-thick sheets of carbon atoms, has high potential to fill this role.

While graphene’s existence has been known for decades, it has only been studied extensively since 2004 due to the difficulty of manufacturing it in high quality and in quantity.

The University of southern California team has produced graphene/polymer sheets ranging in sizes up to 150 square centimeters that in turn can be used to create dense arrays of flexible organic photovoltaic (OPV) cells.

These organic photovoltaic (OPV) devices convert solar radiation to electricity, but not as efficiently as silicon cells.

The energy provided by sunlight on a sunny day is about 1,000 watts per meter square, for every 1,000 watts of sunlight that hits a square meter part of the standard silicon solar cell, 14 watts of electricity will be generated, Organic solar cells are less efficient; their conversion rate for that same 1,000 watts of sunlight in the graphene-based solar cell would be only 1.3 watts.

But what graphene organic photovoltaic (OPV) lack in efficiency, can potentially be compensated by its lower price and, greater physical flexibility.

Researchers think that it may eventually be possible to cover with inexpensive solar cell layers extensive areas like newspapers, magazines or power generating clothing.

In the meanwhile Prof. Ruoff and his colleagues of the mechanical engineering department at the University of Texas at Austin, are studying the basic science in the introduction of graphene-based ultracapacitors for usage in electronics and other fields.

Prof. Ruoff says batteries are relatively slow, they can store energy but require sometime to charge up, and then they distribute energy slowly, over time.

Ultracapacitors can be charged rapidly, within seconds, and discharge quickly, but, right now, they’re not able to store very much electrical energy.

The development of stable and cheaper ultracapacitors is seen as a key step in using wind or solar-generated power, especially if researchers can find methods to enable capacitors to store energy longer, that is not yet possible.

Even with their current storage capacity, the graphene devices could provide quick energy when needed in certain situations on the environmentally friendly way.

They can be used, as an example, to absorb heat generated in braking an automobile or train, and store it for a short time, and employ it for the electrical needs of the vehicle (i.e. starting the car or acceleration)

Check out Sophia’s solar battery charger blog, her personal hobby web site focused entirely on tips to help individuals save energy using solar energy for small devices.

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