我国西部天然气资源十分丰富，占全国天然气总资源量的75%、探明储量的80%，已累计探明储量达13 110×10⁸m³,西部地区已有能力长期稳定年外输气150×10⁸m³。西气东输塔里木天然气有决定意义，目前正在评价的新发现的两个大型气田预计可迅速新增天然气探明储量约5 000×10⁸m³。这些气田储量丰度大，单井产量高，采气成本低。东部长江三角洲地区经济发达，能源短缺，自给率仅为13%，目前能源消费构成中煤炭占76%，城市环境污染严重，是天然气消费的巨大市场。预计2010年天然气需要量253×10⁸m³。西气东输有两个方案，一是塔里木气单独东输，开始年输量100×10⁸m³，第八年开始增加至150×10⁸m³；二是西部诸盆地联合东输，开始年输量150×10⁸m³，第八年开始增加至230×10⁸m³。两个方案均有经济效益，以联合东输方案优点较多。天然气在上海门站每立方米的销售价为1.2～1.3元，是很有竞争力的。项目一旦启动，对东部及西部地区均会带来巨大的好处。

The west of China is very rich in natural gas resources. It has 75% of total natural gas resources and 80% of the proven reserves in China. The total proven reserves of natural gas in the west of China have reached 1 311 billion cubic meters, which makes it capable to provide 15 billion cubic meters of natural gas each year over a long period of time. Such abundant natural gas reserves in Tarim Basin make it economic to transport natural gas from the west to the east of China. It is expected that the two large natural gas fields, which were recently discovered and evaluated, will rapidly increase the area s proven reserves of natural gas by about 500 billion cubic meters.Gas fields in the area have good characteristics such as large reserves per square kilometre, high, output per gas well and low production costs. On the other hand, the economy in the Yangtze River Delta in east of China has already been developed. The Yangtze River Delta faces lack of energy with only 13% of self-sufficiency. At the current stage, 76% of the overall energy consumption is provided by coal which causes serious environmental pollution in the cities. With increasing demand for environment protection, natural gas has a great potential in energy markets. It is estimated that the demand for natural gas will be 25.3 billion cubic meters by the year 2010. There are two options for transporting natural gas from the west to the east. One option is only transporting natural gas produced by the Tarim Basin to the east. The annual transporting volume of the natural gas will be increased from 10 billion cubic meters in the first year to 15 billion cubic meters in the 8th year. The another option is transporting natural gas produced by several basins in the western area to the east.The annual transporting volume of natural gas will be increased from 15 billion cubic meters in the first year to 23 billion cubic meters in the 8th year. The second option has many advantages compared with the first one although both options have reasonably good economic returns. The selling price of the transported natural gas at Shanghai gate terminal is very competitive at 1.2〜1.3 RMB per cubic meter. Once the project to transport natural gas from the west to the east is commenced, it will bring significant benefits for both eastern and western areas.