By embracing advances in solar technologies, Tamil Nadu can continue to lead in this sector
Large-scale solar projects in Tamil Nadu have seen rapid growth in recent years. In the past five years, the cumulative installed capacity witnessed a four-fold increase to 4.4 GW, as of March 2021. Aiding this capacity addition is the State’s reasonably high insolation levels and matching solar potential, estimated at 279GW. The sharp decline in the prices for solar and resulting cost competitiveness is another factor. For instance, auction discovered solar bids reduced significantly, from ₹10.95 in 2010 to ₹1.99 by 2020. Additionally, in response to the ambitious national targets and to spur sector specific development, Tamil Nadu released the Solar Policy of 2019, aiming for 9GW of solar installations by 2023.
Types of technologies
To meet this target, the current capacity would need to be more than doubled. To do this, Tamil Nadu must keep up with market trends and incorporate innovations in the sector to improve efficiency and long-term reliability of solar power plants. ‘First-generation’ solar cells use mono-crystalline and multi-crystalline silicon wafers. While the former is made from a single crystal of silicon (of higher purity), the latter is made by combining several fragments. The efficiency of mono-crystalline panels is about 24%, while for multi-crystalline panels it is about 20%. Crystalline silicon technologies are one of the oldest in the market and occupy 95% of the global photovoltaic (PV) market. Mono-crystalline cells are dominant today. Although mono-crystalline panels are priced higher than multi-crystalline ones, the difference is diminishing and will soon attain parity. This would result in mono panels being preferred over multi due to their higher efficiency, greater energy yield and lower cost of energy.
Newer technologies incorporating crystalline silicon focus on bifacial solar cells, capable of harvesting energy from both sides of the panel. Bifacials can augment the power output by 10-20%. Within this, the Passive Emitter and Rear Contact technology is predicted to gain popularity. However, it is yet to achieve price parity for large-scale deployment. The thin film technologies developed later are classified as the ‘second generation’ of solar PVs. They are manufactured by depositing single or multiple layers of PV material on a substrate, typically plastic or glass. In addition to being used in solar farms and rooftops, thin films with their low thickness, light weight and flexibility are also placed on electronic devices and vehicles, power streetlights and traffic signals. Mainstream thin films utilise semiconductor chemistries like Cadmium Telluride with module efficiencies of around 19%. Other technologies include Amorphous Silicon and Copper Indium Gallium Di-Selenide. However, the efficiency of thin films is lower than that of crystalline silicon. This has affected their popularity and …….
Source: https://www.thehindu.com/opinion/op-ed/a-global-player-in-solar-power/article37079443.ece