electricity production in the Yangtze River Delta area. The capacity of the pipeline is of natural gas annually. The cost of the pipeline was US$5.7 billion. By the end of 2007, the capacity was planned to be upgraded to . For this purpose, ten new gas compressor stations will be built and eight existing stations are to be upgraded. Connections The West–East Gas Pipeline is connected to the Shaan-Jing pipeline by three branch pipelines. The long Ji-Ning branch between the Qingshan Distributing Station and the Anping Distributing Station became operational on 30 December 2005. Source of supply The pipeline is supplied from the Tarim Basin oil and gas fields in Xinjiang province. The Changqing gas area in Shaanxi province is a secondary gas source. In the future, the planned Kazakhstan-China gas pipeline will be connected to the West–East Gas Pipeline. Starting from 15 September 2009, the pipeline is also supplied with coalbed methane from the Qinshui Basin in Shanxi. West–East Gas Pipeline II Construction of the second West–East Gas Pipeline started on 22 February 2008. The pipeline with a total length of , including of the main line and eight sub-lines, will run from Khorgas in northwestern Xinjiang to Guangzhou in Guangdong. Up to Gansu, it will be parallel and interconnected with the first west–east pipeline. The western part of the pipeline is expected to be commissioned by 2009, and the eastern part by June 2011. The capacity of the second pipeline is of natural gas per year. It is mainly supplied by the Central Asia-China gas pipeline. The pipeline is expected to cost US$20 billion. The project is developed by China National Oil and Gas Exploration and Development Corp. (CNODC), a joint venture of China National Petroleum Corporation and PetroChina. West–East Gas Pipeline III Construction of the third pipeline started in October 2012 and it is to be completed by 2015. The third pipeline will run from Horgos in western Xinjiang to Fuzhou in Fujian. It will cross Xinjiang, Gansu, Ningxia, Shaanxi, Henan, Hubei, Hunan, Jiangxi, Fujian, and Guangdong provinces. The total length of the third pipeline is , including trunkline and eight branches. In addition, the project includes three gas storages and a LNG plant. It will have a capacity of of natural gas per year with operating pressure of . The pipeline will be supplied from Central Asia–China gas pipeline's Line C supplemented by supplies from the