Flexible Solar Moves One Step Closer to Mass Market With DaZheng

A 10 year old Chinese startup, DaZheng, has become the first firm worldwide to produce large, flexible perovskite solar panels at scale, with a promised efficiency of 21%. Traditional flexible thin-film solar cells are limited by expensive raw materials and complicated manufacturing processes, which lead to the high cost and limited applications. The new flexible perovskite solar cells from DaZheng are quite promising, owing to their low-cost and simpler fabrication processes. Moreover, they have higher efficiencies and better stability. Fabricated using a combination of the wet-chemistry method and PVD deposition method based on a roll-to-roll production line, a technology first demonstrated by researchers in Japan, DaZheng has taken it to mass production levels now.

DaZheng Micro-Nano Technologies claims to have invested 80 million yuan ($11.8 million) to build the  production line with an annual capacity of 10 megawatts in China’s Jiangsu Province, which hosts some of the largest PV suppliers. The 40 cm by 60 cm panels will be cut into smaller pieces and shipped to smartphone and tablet makers in China.

DaZheng now plans to invest a further 200 million yuan to expand its annual production capacity to 100 MW.

Perovskite solar cells are lightweight, but initially had a power conversion efficiency of around 10% — about half that of silicon cells. Perovskite materials generally have a typical perovskite crystal structure (ABX3). Those perovskite materials suitable for optoelectronic devices are composed of organic or inorganic groups at the A, B, and X sites, of which the semiconductor properties can be tuned by adjusting the composition. Their absorption coefficient is much higher than that of silicon owing to their direct bandgap, while a 500-nm thick perovskite film could absorb most of the visible light. In photovoltaic applications, photon-induced excitons have a longer life, which results in high defect tolerance and low purity requirements as 98%. Simultaneously, the perovskite film can be prepared by the solution method below 130 ℃, which is far lower than that of crystalline silicon. Therefore, the complexity of the production equipment, the cost of materials, and the fabrication energy consumption of perovskite solar cells are far lower than those of silicon-based solar cells and other existing photovoltaic technologies.

Being flexible, they open up a whole new segment of potential use cases, be it windows, walls or even large vehicles and other areas.

DaZheng, by mass producing them for large panels has managed to bring down the price differential with silico cells to 3x, and is confident it can bring it further down to 2x. At that price, or effectively the silicon cell price of say, 2015, the possibilities will be endless to use flexible solar.