Researchers at Glasgow Caledonian University have developed a solar concentrator technology for glazing that connects to solar photovoltaic cells and is able to generate up to four times the power of conventional solar PVs.
The devices cost just £1 each to produce and are arranged in a grid across a window or skylight. Each one is made up of several square-ended prisms that catch sunlight in different angles and channel the energy into PV cells.
The GCU researchers, led by senior lecturer Dr Roberto Ramirez-Iniguez, have patented the technology and its application for building integrated PV. Companies in Malaysia and the Middle East interested in developing it into a commercial product have already contacted the team.
"What is innovative about this design is the geometry which allows maximum gain on both planes. It is also compact and reduces the amount of PV cell material needed and, therefore, the cost of the system."
Dr Roberto Ramirez-Iniguez, Glasgow Caledonian University
The researchers claim that using a grid of concentrators and cells within a double-glazed window could have a significant impact on reducing energy consumption in the home, also generating ambient light as a by-product.
Dr Ramirez-Iniguez commented: “There has been lots of research into two dimensional and 3D concentrators. What is innovative about this design is the geometry which allows maximum gain on both planes. It is also compact and reduces the amount of PV cell material needed and, therefore, the cost of the system.”
Although the concentrator is a static system, it effectively tracks the sun’s path to optimise solar energy capture throughout the day and from season to season. Its optical structure has also been designed to take into account the fact that the sun’s path deviation from summer to winter is far less than the deviation from sunrise to sunset. The entrance aperture and concentrator profile have been optimised to redirect sunlight to the exit aperture and to the PV material.
“The devices can be attached to any type of PV cell, what the concentrator does is to increase the irradiance at the PV cell surface. Solar energy conversion efficiency is dependent on the type of cell used and not on the concentrator,” said Dr Ramirez-Iniguez.
Development of the technology involved software simulation, 3D printing and moulds, which led to the production of commercially viable prototypes. A variety of different materials was tested before
a mass production technique was discovered that would allow each concentrator to be produced for less than £1 each.
The team claims the optical element could also be used to collect visible and infrared radiation for applications such as sensing and optical wireless communications. As part of his research, Dr Ramirez-Iniguez is also investigating low energy consumption illumination sources based on beam shaping optics.
