College of southern California scientists show us a more efficient use of graphene solar panels
Can you imagine people powering their cellphone or music/video device while jogging under the sun?
A University of Southern California team has produced flexible transparent carbon atom films that may have great potential for a new breed of solar cells.
Inside a paper recently published in the journal ACS Nano, researchers stated that organic photovoltaic (OPV) cells have been proposed as a means to achieve cheap energy due to their ease of manufacture, light-weight, and compatibility with flexible substrates.
This work indicates that graphene, an extremely 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 many years, it has only been studied extensively since 2004 because of the impracticality of manufacturing it in high quality and quantity.
The University of southern California team has produced graphene/polymer sheets ranging in sizes nearly 150 square centimeters that in turn may 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 power provided by sunlight on a sunny day is approximately 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 could 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 development of graphene-based ultracapacitors for use in electronics and various fields.
Prof. Ruoff says batteries are relatively slow, they can store energy but take time to charge up, and then they distribute energy slowly, in time.
Ultracapacitors can be charged very quickly, within seconds, and discharge rapidly, but, right now, they’re not able to store very much electrical energy.
The development of stable and cheaper ultracapacitors should be a key step in using wind or solar-generated power, particularly if researchers can discover ways to enable capacitors to store energy longer, which is not yet possible.
Even with their current storage capacity, the graphene devices could provide quick energy when needed in certain situations on the eco-friendly way.
They may be used, for example, to absorb heat generated in braking a vehicle or train, and store it for a short time, and then use it for the electrical needs of the vehicle (i.e. starting the car or acceleration)
About the Author – Sophia H. Walker writes for the solar powered battery charger blog, her personal hobby web log devoted to tips to help people save electricity using solar power for small instruments.