Who is the ultimate winner of photovoltaic power generation?

What is the technical route of China's future photovoltaic power generation, crystalline silicon or thin film? The first solar power company in the United States plans to build the world's largest photovoltaic power plant in Ordos, Inner Mongolia, and this debate has temporarily drawn a full stop.

At present, solar cells can be divided into three categories: silicon-based batteries, thin-film batteries and new batteries. New solar cells are made of expensive rare earths and they are mainly used in the aerospace field, so they are negligible. In the civilian market, silicon-based and thin-film batteries are still the mainstream.

Silicon-based batteries include monocrystalline silicon and polycrystalline silicon, of which polycrystalline silicon batteries dominate, and the technology is the most mature. China's first-generation photovoltaic cell module manufacturers, such as Suntech, Artes, Changzhou Tianhe and Tianwei Yingli, started from polysilicon and completed the overseas listing.

The most important feature of silicon-based batteries is their high photoelectric conversion efficiency, which can generally reach 14% to 19%, which is currently beyond the reach of thin-film batteries. Thin-film batteries are made of sensitized materials that are attached to the surface of glass, stainless steel, and other materials in a few microns. Although they were developed in the 1970s, due to the low photoelectric conversion efficiency, they have no conditions for large-scale promotion.

Silicon-based battery short board is also very obvious, one is the raw material cost is too high, the volatility is relatively large, since last year, polysilicon on the international market has staged a roller coaster market, disrupted the normal production and operation of some companies; In addition, the silicon industry It is a highly polluting and energy-consuming industry. From purification and casting to slicing and assembly, the entire process consumes a lot of power. China produces polycrystalline silicon batteries at the expense of high energy consumption and exports them to developed countries such as Europe and the United States. This production model has also been criticized.

Because of this, thin-film solar cells gradually move to the front desk.

The premise of large-scale commercial use of thin-film batteries is to increase the photoelectric conversion efficiency. Although the thin-film battery technology has developed by leaps and bounds in decades, but so far, no one thin-film solar cell company announced that the conversion efficiency of more than 10%, usually about 6%, Hebei Xinao photovoltaic claims its photoelectric conversion efficiency 8%, which is already the highest in the industry. Even so, it is only half of silicon-based batteries. However, thin-film batteries have become popular because of low power consumption, low cost, and cost advantages. Some polysilicon battery companies have also begun to introduce large-scale thin-film battery production lines.

More companies directly started manufacturing thin-film batteries, such as Tianwei Yingli of Baoding, Hebei, who invested 1.2 billion yuan to import 46.5 megawatts of thin-film battery production lines from abroad, and has just started mass production in August. Johnson & Johnson, headquartered in Shanghai, also set up a thin-film battery demonstration area in Nantong, Suzhou and other places.

A set of data can illustrate that in recent years, thin-film batteries have developed faster than silicon-based batteries: In 2006, the market share of thin-film solar cells was 8.2%, reaching 12% in 2007, and even more than 15% in 2008, and this year still Maintain a high growth trend.

“There are still misunderstandings about amorphous silicon cells in the market.” China Merchants Securities pointed out in a research report that “subjectively, the higher the conversion efficiency, the better the competitiveness of the company, but the actual situation is the level of conversion efficiency. In fact, it is relatively speaking, the key lies in the cost-effectiveness of the product. Even if the conversion efficiency is high, but the manufacturing cost is also high, there is no market for products with higher conversion efficiency.”

However, the prospects for thin-film batteries are also uncertain, especially in the context of the international polysilicon prices falling from 450 US dollars/kg to 50 US dollars/kg, the price advantage of polysilicon batteries highlights, if the polysilicon battery market is warming, it is likely that Means that the nightmare of thin film batteries has arrived. In fact, the rapid development of thin-film batteries in the past two years is an alternative that some companies cannot afford to pay for high polysilicon prices.

New energy such as photovoltaic power generation is encouraged by the state, but what kind of technical route China adopts to develop China's photovoltaic industry has been debated for several years. Silicon-based battery companies believe that polysilicon has the advantage of high conversion efficiency, and the technology is relatively more mature, but the film Battery companies believe that cost advantages determine that they should give priority to development.

The First Solar Company is the world's largest manufacturer of solar cells. The technology path used is thin-film batteries. In comparison, China's Wuxi Suntech focuses on silicon-based batteries, and its market share is giving way to rival First Solar. According to a research report issued by the China Investment Advisor on September 8, it is expected that the market share of the first solar company will increase from 7.5% to 12.8% in 2009, while Wuxi Suntech will slightly decrease from 7.3% to 6.9%.

The First Solar Company won the biggest ever order from China. For many Chinese PV companies, it means that the controversy has temporarily come to an end. Thin-film technology is more easily recognized by the market than crystalline silicon technology.