Solar cells that can be printed directly onto roof steel and laptop bags are currently being developed in an effort to increase renewable energy sources.
Credit: University of Melbourne, David Jones
SYDNEY: Printable solar cells – which can be etched onto ‘plastic paper’ in much the same way as money – might soon be incorporated into the steel in your roof and feed directly into the grid.
Known as ‘organic photovoltaic cells’, they can be made from “basically any organic molecule that can absorb light and can be formulated into an ink,” said David Jones from the University of Melbourne’s Bio21 Institute and program coordinator of the Victorian Organic Solar Cell Consortium.
“These cells are going to change the way the public thinks about solar power,” said Jones. “We now need to take what we’ve done in the lab and do it at a much larger scale.”
Looking for an efficiency boost
The solar cells are made up of many layers of printed materials, with the active layer containing two different organic polymers stacked up top of each other – one that repels electrons and one that attracts them.
This sandwich design works to generate charge from sunlight, which is directed to another layer containing a printed electron.
Jones and his colleagues have shown that these cells can harness about 4 or 5% of the Sun’s energy – which is, unfortunately, less efficient than silicon solar cells currently on the market, which harness up to 20% of the Sun’s energy.
More cost efficient than silicon
But the printable cells are 100–150 nanometres thick and only around one centimetre wide, and because they can be printed side by side on cheap plastic, they have the potential to be more cost efficient than silicon solar cells.
With the use of recent funding from the Victorian Government, the scientists will work towards improving the commercial features of the technology, said Jones.
“With the grant we will need to improve efficiency and look at durability, because the amount of time that they last on your roof is obviously going to be important. We also need to learn how to print them fast."
Solar steel
While the group is hoping to have the cells available on small consumer items such as laptop bags within the next five years - a step that will allow them to continue durability testing the cells in the field - more long term plans are being put in place to incorporate the dyes into established industries.
“One of our partners is interested in printing solar cells directly onto their steel for roofs,” said Jones. This is part of a growing industry known as printed electronics, and could one day see solar cells not only printed by traditional printing companies, but also spray painted onto different fabrics and materials.
Andrew Blakers, the director of the Australian National University’s ARC Centre for Solar Energy Systems in Canberra said that while the consortium was getting a lot of momentum, it was still early days. “It’s too early to judge the commercial prospects of organic photovoltaics (OPV) in competition with silicon solar cells, solar thermal and photovoltaic concentrators, but OPV is well worth investigating."
<3
Brilliant