Improved Technology leads to less consumption of indium
New energy is not a new term in the past decades, and the promotion of new energy development such as solar energy has been included in the national strategy for many countries like China, Saudia Arabia and many others. Therefore, thin film solar, a strong competitive product to traditional silicon solar, is getting more important in the field of renewable energy. Copper Indium Gallium Selenium (CIGS) is one of the most important technology roadmaps among all the thin film solar technologies. It is mainly because CIGS has various advantages, such as ultra-light, flexible, high conversion efficiency, high weak-light power generation ability. And among the 4 elements (CIGS), indium (In) plays an important role in the technology.
As a rare earth element, indium is mainly used in the manufacture of low-melting alloys, bearing alloys, semiconductors and electric light sources. At present, 70% of indium is used as an indium tin oxide (ITO) sputter target for transparent electrode coating, while its annual demand is around 200 tons. A well-known application of ITO is iPhone’s touchscreen, which can magically sense when you touch the screen. Together with the wide use of indium and the rapid development of thin film solar energy, especially CIGS batteries in recent years, indium consumption has become a focus, as the proven reserve of indium is only 16,000 tons.
As the world’s largest thin-film power company, Hanergy expressed no worries to the limited indium reserve. “As the CIGS manufacturing and recycling technologies are advancing, 1GW CIGS batteries will only consume around 5 to 6 tons of indium, and CIGS is gradually reducing its relying on indium consumption,” said a Hanergy spokesperson.
In addition, increasing the proportion of gallium components or thinning of the battery film layer in the CIGS batteries can also effectively reduce the amount of indium consumption. This will lead to the reduction of indium use in thin-film solar battery manufacturing.
Over the last years, large state-owned enterprises such as CHN ENERGY Investment Group (formerly called Shenhua Group), China National Building Material Group, renowned private enterprises such as Hanergy Group and Jinjiang Group have unanimously invested more than RMB 47 billion (US$6.8B) in the thin film solar market since 2015.
It is caculated that the indium recovery rate in Hanergy’s production line is 98%, meanwhile the recovery rate of indium on solid waste produced by RC coating and the ineffective Web is 95%. What’s more, the increase of conversion efficiency rate and production yield rate of CIGS chip results in reducing demand for indium by about 15%.
While new energy companies continue to upgrade their technology to reduce the usage of indium, the improvement of mining, drilling, purification and recycling technologies also results in discovering more indium resources and proven indium reserves.
According to a report of Accenture, a renowned international consulting firm, by 2020, the global thin film solar energy development market will reach to RMB 1.14 trillion (US$1,658b), while the Chinese market will exceed RMB 200 billion (US$29B). In a future time when CIGS thin film industry enters a track of high-speed development, the era of green building, and low-carbon life will also come to real in short.