Energy & Power
Rochester researchers awarded $1.5 million to develop plastic solar concentrators
By Anthony Capkun
September 8, 2015 – University of Rochester researchers have been awarded $1.5 million to develop a technology that could reduce the cost of electricity from solar power; specifically, the technology would replace the area that needs to be covered with solar panels with less-expensive, plastic solar concentrators and fewer solar cells.
Led by prof. Duncan Moore and research engineer Greg Schmidt, the Rochester team will develop a planar light guide using micro-optics to capture, orient and concentrate direct sunlight onto a single photovoltaic (PV) cell. Using plastics, their light guide will concentrate sunlight so that fewer expensive PV cells will be needed.
“The most-efficient PV cells are very expensive—up to $50,000 per square metre,” said Moore. “If we could concentrate the sunlight 500 times, we’d need fewer of these cells, as the solar concentrator would cover the bulk of the area. This would mean the cost would be $100 per square metre.”
The team’s system will be very thin (less than 3-mm thick) and lighter than similar, existing panels. This will also help reduce the cost, as it will be easier to move the whole system to face direct sunlight.
“With this grant, we will be aiming to produce the next generation solar concentrator—one that will be cheaper to make and can be produced at a larger scale,” said Moore, adding that his team already has an early prototype that demonstrates the potential of the technology.
The team has already identified a potential commercial use. “One advantage of using our approach is that our planar light guide is translucent, so any light that is not concentrated into the PV cell will go through the material,” said Moore. “This is of interest to architects, as it provides a material that will be letting light through at the same time as helping produce electricity from solar energy.”
The team holds five patents for its approach to solar concentrators. The group produces an array of small plastic lenses—each about the size of a pen tip—on the surface of the material. These focus the light a certain depth below the surface of the material, where there are air ‘bubbles’ of a specific shape. These act like prisms, guiding the light along the material to the edge. The PV cells only need to be placed along one edge of the material, where the light guide formed by the tiny air prisms concentrates the sunlight.
Moore’s team will work with three partner companies—RPC Photonics, ORAFOL and ARZON—to develop these designs to be commercially viable.