Spectral filters could boost the performance of concentrated photovoltaic thermal systems

A concentrated photovoltaic thermal system is a hybrid system that combines concentrated photovoltaic and solar thermal technology and could help increase the share of renewables in the energy mix. A major drawback of the technology is that when the intensity of the solar radiation increases, so does the temperature, which compromises the electrical efficiency of the photovoltaic cell. 

Funded by the Marie Skłodowska-Curie Actions programme, the NANOSPLIT project aims to design entirely new nanofluid-based spectral splitters to significantly improve the electrical efficiency of the cell. These splitters will filter out wavelengths that are not absorbed by the cells and thus create excess energy wasted as heat.

The deficient utilisation of the full solar spectrum for power generation in conventional hybrid CPV/T technologies leads to a detrimental decrease in PV cell efficiency due to elevated temperatures. The aim of this research is to break entirely from conventional design principles and to develop a novel nanofluid spectral splitter (NSS)-assisted hybrid CPV/T collector which will benefit from a step-change improvement in electrical efficiency via the optical filtering of spectral wavelengths that are inefficiently utilised by the PV cells in the form of heat, enabling the delivery of high-temperature heat and enhancing the life of the PV cells. 

Plasmonic nanofluid acting as the NSS will be used for visible light harvesting, while the high grade heat generated by the splitting process will be stored in a thermal storage and utilised directly in domestic or commercial applications. The NANOSPLIT project is highly interdisciplinary and covers process engineering, chemistry (nanomaterials synthesis), physics (PV), energy engineering (solar collector design, development), mechanical and chemical engineering (thermal storage and power generation). 

The host supervisor, Prof. Christos Markides, has world-leading experience in waste-heat recovery and utilisation and solar energy technologies. He will provide expert training and support for design and development of the innovative hybrid PV/T concept, while, Dr. Sandesh Chougule, a leading Indian researcher, will bring his knowledge on the novel application of nanofluids in solar spectral beam splitting to the host(s). 

In addition, design of concentrating collectors will support NANOSPLIT through a planned secondment. The high-quality two-way transfer of knowledge required for this project will ensure that research goals are achieved, whilst also presenting a great opportunity to accelerate the academic career of the researcher. Completion of NANOSPLIT will lead to significant economic and societal impacts on the EU and world.

Coordinator

• IMPERIAL COLLEGE OF SCIENCE TECHNOLOGY AND MEDICINE

Start date: 1 November 2021 - End date: 31 October 2023