Background
Panels implementing silicon-based solar cells currently dominate the PV market. Their module efficiency is circa 17-19% and cost around $1 (between £1.70 to £1.10 in the UK [1]) per watt depending on the silicon version. More efficient solar panels (40%)[2] come at higher cost ($300 per watt), and such technologies are only implemented in specific roles. However, recently – Insolight – a Swiss start-up, has developed a new CPV panel that implements both technologies to create a more efficient and low-cost PV module[3].
Concentrated solar photovoltaic [4]
Insolight Concentrator Photo Voltaic panel
The CPV module developed by Insolight uses planar optical micro-tracking to focus the sunlight beams on an array of highly efficient solar cells. This system can adjust depending on the time of the day and season. The multi-junction cells used can harness energy from a broader spectrum of light thanks to the implementation of materials such as of gallium arsenide and gallium indium phosphide. Such solar cells are very costly to produce. However in the Insolight module, cells cover only 0.5% of the surface, cutting costs significantly.
The panels were tested at the IES-UPM-Universidad Politécnica de Madrid under CSTC (Concentrator Standard Test Conditions) conditions and recorded a module peak efficiency of 29%. The modules were also tested in real-life conditions for a whole year on a pilot installation at the Swiss Institute of Technology in Lausanne and successfully endured heat-waves, winter conditions and storms.
Insolight is partnering with solar manufacturers to licence the technology and plan an industrialization strategy for large-scale production. Insolight’s CEO expects the module to be on the market by 2022[5]. Mass production can cut costs to $0.30 per watt[3] and the module can reduce electricity costs by 30%[5]. Insolight panels are designed for sunny conditions, however they can be coupled with standard PV panels to gather diffused sunlight in cloudier conditions.
Conclusion
Conventional solar panels are reaching maturity and new approaches to increase energy yield and reduce costs should be explored. Concentrated solar power might be a valuable solution to achieve these targets. There are however other solar PV technologies on the horizon, one of which is perovskite solar cells. It is expected that cells made with perovskite material will be highly efficient, flexible and extremely inexpensive.
References
[1] Solar photovoltaic (PV) cost data, Gov.UK, date: 31st May 2018, accessed: 04th April 2019.
[2] Champion Module Efficiencies, NREL, date: 2018, accessed: 04th April 2019.
[3] A highly efficient rooftop solar panel based on space technology, The Economist, date: 30th March 2019, accessed: 04th April 2019.
[4] Robins home to Southeast’s first-of-its-kind solar technology, date: 18th December 2009, accessed: 04th April 2019.
[5] Insolight Technology, Insolight, accessed: 04th April 2019.
