Every country has to do its utmost, to stop using fossil fuels and move towards renewable sources of energy. As the cost of the electricity produced from solar PV dropped to Rs 2 per kWh and lower than that of coal-based electricity, India has made significant progress in deploying solar. Yet, the country imports most of the solar panels from China and there is an urgent need to change this.
China is the leader in value chain
The manufacturing of crystalline silicon solar PV panels, which constitutes over 97 per cent of global production, involves four steps. The first is production of polysilicon. China’s capacity here is almost twice that of the world’s demand. This allows them to sell at any price, making polysilicon manufacturing unviable anywhere else. The second step is making wafers and crystals using the polysilicon. China’s manufacturing capacity just about matches current demand. As the demand grows, a chance to compete is possible here. The third step is manufacturing of solar cells using the crystals and the final step is making of the solar panels. Making of silicon solar-cells is an established technology involving high investment. Today few large companies in India are setting this up. It would however be difficult to compete with Chinese companies without protection. This final process involves minimal technology and has a low value-add. Some fifty odd solar panel manufacturers have emerged in India over the last few years. If China does not dump panels, they would be able to compete and manufacture for India, as well as look at exports.
RSOLEC to manufacture solar crystals and wafers in Chennai
India can seize the opportunity and emerge as an alternative to China in the manufacturing of solar crystals and wafers. Even though the process and the manufacturing set-up is well known, it is necessary to develop unique design of crystal puller internals known as the hot-zone, an optimal process for the hot-zone and the complementary process control algorithm necessary to grow crystals. This is accomplished periodically on the present technology platform. However, technologies under development, such as continuous czochralski and magnetic czochralski, help improve both quality and performance, and can also be implemented on the present manufacturing platform. This would enable manufacturers to reduce costs. Renaissance Solar and Electronic Materials (RSOLEC) has recently proposed to establish a facility in Chennai to manufacture solar crystals and wafers. Led by some highly experienced professionals in India, it has set up a subject matter expert council and an advisory council with very prominent technology-leaders across the world, with an aim to optimise the hot-zone design, process and control scheme. The objective would be to make solar PV crystals and wafers at a cost less than what the Chinese companies incur. Theoretically, there is a possibility to supply even to the Chinese manufacturers of solar-cells. Only with superior technology, design, process and control schemes, one can compete in the global arena. The company will set up the plant in near-future and has tied up with IITM Research Park for research and development activities.
First Solar is the only alternative to existing technology
While it is the silicon solar-PV technology that is primarily used for solar power generation all over the world, there has been a lone company in the United States, First Solar, which has kept the flag flying with an alternate technology to manufacture and deploy Cadmium Telluride (CdTe) based solar panels. Early work on this technology was carried out by an IITM alumnus in the United States. First Solar advanced the technology and started making panels, which could compete with the silicon PV panels, both in terms of costs as well as the percentage of solar irradiation it captures (called energy efficiency of the solar panels). With high R&D cost to enhance energy efficiency of silicon solar-PV panels and Chinese manufacturers dominating the market with cheaper alternatives, it is often believed that CdTe panels would not be able to compete. However, CdTe captures more sunlight during mornings and evenings (low sunlight hours), and works better at higher temperatures. This is typically the case in tropical countries like India, with lower degradation in efficiency over the years. The net result is that CdTe solar panels over its lifetime provides as much, if not higher energy as compared to the silicon based solar PV panels. Recognising this, India did woo First Solar to set up a panel manufacturing plant in Chennai and the production started in 2023. It has set up its R&D at IITM Research Park and is now collaborating with Indian researchers to enhance its technology.
Perovskite, the next gen technology
With RSOLEC and First Solar, we have two flag bearers that would help India to compete with China in terms of technology for solar PV, especially as it aims to use this to enhance its power generation capacity from the current value of 73.3 GW to 500 GW over the next decade or so. At the same time, India needs to pursue aggressive R&D in Perovskite, the emerging and the next generation solar PV technology, particularly for use as a second layer over silicon or CdTe panel to further enhance its energy efficiency.
Solar PV is one of the most important technologies for India as it takes on the rising threats of climate change. While deployment using imports is welcome, India’s large demand makes it imperative to pursue its own R&D and technology. IITM Research Park recognises this crucial role and through its 10X programme aims to develop commercially viable technologies in this arduous fight against climate change, striving to keep India in leading this charge ahead.
