Grant: Strategic Projects - Group

The growing need for clean and sustainable energy has signified sunlight as an abundant and distributed resource. However, this resource is heavily underused, mainly due to the high cost (>$2 per watt) and the low conversion efficiency (~19% for multicrystalline silicon) of today's photovoltaic (PV) panels. To reach a retail cost parity <$1 per watt for solar energy, novel solutions are required to cut manufacturing cost and to improve efficiency of PV devices. Silicon PV panels are finished with metallic fingers that collect the current and let the sunlight reach the device through the openings, but inevitably lead to ""shadowing effects"" over ~10% of the panel area. Amorphous silicon thin film PV devices are deposited on glass coated with transparent conductive oxides (TCOs) such as indium tin oxide (ITO). ITO is expensive, brittle and can only be deposited at high temperature (250C) without compromising on conductivity and transparency. The objective of this proposal is the development of a nature-inspired multiscale mesh of nanocomposite fibres (NCFs) for replacing metallic grids and TCO electrodes of PV panels so as to reduce the cost and efficiency losses associated with this electrode. A thin (<20 nm) mesh with embedded conductive nanostructures such as nanotubes (NTs) and nanowires (NWs) can carry a high current but absorb light negligibly (>90% transmission). Novel multiscale ordering and alignment in the structure of the mesh will be used (similar to veins of a leaf) to achieve desired conductivity levels while minimizing the amount of NWs and NTs needed. The NCF mesh will be deposited by an electrospinning process that is scalable to substrates including plastic in a roll-to-roll manufacturing system. Challenges for integration of the NCF mesh with Si and thin film PV panels will be addressed to achieve high-surface-area contacts. The proposed research will have short term impact on improving efficiency and cutting cost of well-established PV panels, and develops materials and processing technologies that will revolutionize manufacturing of future panels. This research is critical for strengthening Canadian industries in clean energy and nanotechnology and training of highly qualified personnel.