Inside one of the world's largest solar panel makers

Apr 03, 2016

Yingli supplied solar panels used for the Qinghai Wulan and Geermu project, the tallest and largest solar power project in the world.

One out of every ten solar panels sold across the world is produced by one company in China, operating under the brand name ‘Yingli Solar.'

One of the firm's satellite factories is located in Haikou, a city in Southern China's Hainan Province, in a large but unassuming complex.

Inside the factory, visitors get a peek into the intricate process of producing solar panels and get up-close with displays of a range of products such as toys, torches, bulbs and computer monitors.

The unassuming neighbourhood

Solar panels convert light energy from the sun into electricity through the photovoltaic effect. A typical solar power system requires a panel an inverter, a battery and connection wiring.

How solar panels are made

Polysilicon ingots or blocks of silicon are melted and sliced into wafers. Individual wafers are then sliced and subjected to a surface etching process.

The Precious stones used to make the silicon blocks are imported from Germany and South Korea.

The wafers are then cleaned, furnaced and layered with semiconductor around the entire outer surface of the cell.

An anti-reflective coating is applied to the top surface of the cell, and electrical contacts are imprinted on the surface of the cell.

Workers at the factory sort the cells according to type in adjacent rooms. Aluminum, glass or plastic material is layered the back of each cell, usual with the help of robots.

Inside the factory

Workers seen here sorting panels according to type

Each cell is electrically tested, sorted based on current output, and electrically connected to other cells to form cell circuits for assembly into solar panels.

Big firm

Yingli Solar was established in 1998 by a Chinese national named Liansheng Miaoa. In 2007, Yingli Energy Holding Company Ltd listed on the New York Stock Exchange.

In 2012, Yingli Green Energy reached a production capacity of 2,450 MW per year, making it the largest solar module manufacturer in the world in terms of module production capacity.

The company develops, manufactures, and sells solar modules under the brand name Yingli Solar in Germany, Spain, Italy, Greece, France, South Korea, China, Japan, Australia, and the US.

Yingli was sponsor of the 2014 FIFA World Cup. The firm has also been a sponsor of FC Bayern München and the U.S. Soccer Women's and Men's National Teams.

New technology

Yingli Solar manufactures both monocrystalline and multicrystallin silicon solar panels. The firm has since developed new technology to create a new, more efficient solar cell known as PANDA.

Polysilicon blocks

Silicon and polysilicon blocks

Officials at the plant say the new technology has increased the solar cells' rate of conversion of light into electricity from 15.4% to 19.2% by the end of 2015.

One of Yingli's most recent technologies is a type of solar panel designed to power the entire lighting system of a car.

Research into a variant of the technology to power car engines is underway at the firm, officials disclosed during the tour of the facility.

Solar power potential

Solar power belongs to a category of clean energy. By 2015, Yingli Solar had filed 1,730 patent applications pertaining to solar energy solutions and production of solar modules.

Yingli supplied solar panels used for the Qinghai Wulan and Geermu project, the tallest and largest solar power project in the world by 2011.

A solar car roof

To-date, the firm boasts of 14 GW of solar panels deployed in over 70 countries worldwide. Solar power has been used to power housing estates, industrial park, community shelters and agricultural projects, including the Dingzhou Guoxiang farm.

It is estimated that 10 GW of solar panels can produce 11 billion kilowatt hours of clean electricity, saving 4.4 million tonnes of standard coal and reduce 10.3 million tonnes of carbon emissions, equivalent to reforestation of 190,000 hectares.

China, the world's largest energy consumer targets to generate at least 230 million kilowatts from solar energy by 2020, as part of efforts to reduce reliance on coal.