Scientists at Sandia National Laboratories in the US have developed tiny glitter-sized photovoltaic cells that could turn a person into a walking solar battery charger.
The tiny cells could turn a person into a walking solar battery charger if they were fastened to flexible substrates molded around unusual shapes, such as clothing.
The solar particles, fabricated of crystalline silicon, hold the potential for a variety of new applications.
They are expected eventually to be less expensive and have greater efficiencies than current photovoltaic collectors that are pieced together with 6-inch- square solar wafers.
The cells are fabricated using microelectronic and icroelectromechanical systems (MEMS) techniques common to oday's electronic foundries.
Sandia lead investigator Greg Nielson said the research team has identified more than 20 benefits of scale for its microphotovoltaic cells.
These include new applications, improved performance, potential for reduced costs and higher efficiencies.
"Eventually units could be mass-produced and wrapped around unusual shapes for building-integrated solar tents and maybe even clothing," said Nielson.
This would make it possible for hunters, hikers or military personnel in the field to recharge batteries for phones, cameras and other electronic devices as they walk or rest.
Such microengineered panels could have circuits imprinted that would help perform other functions customarily left to large-scale construction with its attendant need for field construction design and permits.
According to Sandia field engineer Vipin Gupta, "Photovoltaic modules made from these microsized cells for the rooftops of homes and warehouses could have intelligent controls, inverters and even storage built in at the chip level."
"Such an integrated module could greatly simplify the cumbersome design, bid, permit and grid integration process that our solar technical assistance teams see in the field all the time," he said.
Solar concentrators - low-cost, prefabricated, optically efficient microlens arrays - can be placed directly over each glitter-sized cell to increase the number of photons arriving to be converted via the photovoltaic effect into electrons.
The small cell size means that cheaper and more efficient short focal length microlens arrays can be fabricated for this purpose.