Professor Chongwu Zhou and his team of researcher at the University of Southern California produced flexible transparent carbon atom films that have great potential for a new breed of solar cells suitable to be integrated into garments.
Graphene OPV (organic photovoltaics) has been on the research agenda for a couple of years as means to transport electronics from hard substrate PCB (Printed Circuit Board) to soft, flexible substrates suitable to be wrapped around curved surfaces or even in clothing.
Professor Zhou’s lab reported the large scale production of graphene films by chemical vapor deposition three years ago. In this process, the USC engineering team creates ultra thin graphene sheets by first depositing carbon atoms in the form of graphene films on a nickel plate from methane gas.
These OPV films convert solar radiation to electricity, but not as efficiently as silicon cells like in rigid or the flexible solar cells commercially available today.
The power provided by sunlight on a sunny day is about 1000 watts per square meter. ‘For every 1000 watts of sunlight that hits a one square meter area of the standard silicon solar cell, 14 watts of electricity will be generated,’ says Lewis Gomez De Arco, a doctoral student and a member of the team that built the graphene OPVs.
Organic solar cells are less efficient; their conversion rate for that same one thousand watts of sunlight in the graphene-based solar cell would be only 1.3 watts. It is not as bad as this numbers suggest. Assuming this technology can be further developed into volume production with reasonable low costs, large areas could be covered with OPV films which are not suitable for rigid, planar surfaces.
OPV solar cell technology is yet another promising step into wearable power technologies of the future but as most of these developments at research stage, it will take a (very) long time until one of these hot technologies will make it into the commercial consumer market.