ZHOUSHAN, July 14, 2016 (Xinhua) -- Workers test the 500 KV polyethylene submarine cable in Zhoushan marine power transmission technology research center in Zhoushan, east China's Zhejiang Province, July 14, 2016. China's first domestically produced 500 KV polyethylene submarine cable is under final test and will be used for the transmission line project from Ningbo to Zhoushan. (Xinhua/Xu Yu)