URUMQI - About 38.7 billion cubic meters (bcm) of natural gas was piped from Central Asia to China through a major energy project last year, the project operator said Friday.

The amount represents a 13.4 percent annual increase as China imported more to meet rising demand for clean energy.

The China-Central Asia pipelines have sent 203.2 bcm of natural gas to the world's second-largest economy over the past eight years.

As China's first overland cross-border gas project, it is key to China's efforts to improve its energy mix and ensure its energy security. It provides around 15 percent of the country's annual natural gas consumption.

The pipelines are made up of three routes with a combined annual capacity of 55 bcm. The first route went into operation in December 2009. The pipelines pass through countries such as Uzbekistan and Kazakhstan.

The project has benefited over 300 million people in China.