Researchers from Glasgow Caledonian University (GCU) have developed a novel optical concentrator which, at a cost of just £1 each, can be used in windows to capture energy from the sun to generate electricity and ambient light within the home.
The square-ended prisms catch light at a range of different angles, channelling the energy to photovoltaic cells (which convert light to electricity) to generate four times more electricity than cells alone could produce.
Using a grid of concentrators and cells within a double-glazed window could have a significant impact on reducing energy consumption in the home, producing electricity that can be used throughout the building with the resulting environmental benefits.
GCU researchers, led by Dr Roberto Ramirez-Iniguez, have now patented the solar concentrator and the design algorithm for the production of new optical elements for building integrated photovoltaic systems.
Research has involved software simulation, 3D printing and moulds, leading to the production of commercially viable prototypes.
The concentrator is capable of providing gain on two planes. Such a concentrator can act as a static system which tracks the sun’s angle to best capture solar energy throughout the day and from season to season.
The team has researched a variety of different materials and has found a mass production technique which would allow each concentrator to be produced for less than £1 each.
Further, the optical structure has 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 and the entrance aperture and concentrator profile have been optimised to redirect sunlight to the exit aperture and to the PV material.
The innovative optical element could also be used to collect visible and infrared radiation in applications such as sensing and optical wireless communications.
Dr Ramirez-Iniguez said:
“There has been lots of research into 2D and 3D concentrators, which tend to be designed for a single field-of-view value. 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 Ramirez-Iniguez is also investigating low energy consumption illumination sources based on beam shaping optics.
In their effort to reduce electricity bills and to fulfil their commitment to reducing CO2 emissions, councils across the UK have proposed to replace energy inefficient lights with energy efficient solutions based on LEDs.
However, some LED-based streetlights fail to produce a footprint that complies with relevant national and international standards.
Working with Optical Antenna Solutions, GCU secured £25k from the Energy Technology Partnership (ETP) as part-funding for a PhD studentship to explore the use of non-imaging optics in combination with LEDs.
The project will design and evaluate an optimised low energy consumption LED-based illumination system for installation on lamp posts above six meters.
Pictured is Dr Ramirez-Iniguez with one of the prisms