PV News: From June 4th to 6th, the 13th (2019) International Solar Photovoltaic and Smart Energy (Shanghai) Exhibition and Forum was officially opened in Shanghai. In the first day of the Exhibition, two giants of the photovoltaic industry, Tongwei (600438, SH) and Longi (601012, SH) held a strategic cooperation signing ceremony at the exhibition. The two sides signed a cooperation agreement on high-purity crystalline silicon and silicon wafer cooperation and agreed to support each other's advantageous industrial chain to develop and to achieve deep-level cooperation.