BEIJING - The Chinese government has established a goal of having green buildings account for 30 percent of new construction projects by 2020, according to an official document released Sunday.

The document, which was jointly released by the Ministry of Finance and the Ministry of Housing and Urban-Rural Development, marks the first time for China to set a goal for the development of green buildings.

The move underlines China's intent to speed up the development of energy-efficient construction following other documents published earlier this year aimed at the same goal.

According to the document, the government will speed up the sector's development by increasing policy incentives and improving industry standards, as well as promoting technological progress and the development of related industries.

The document also specifies a goal of bringing China's building energy consumption ratio closer to that of developed countries by 2020.

Different from ordinary buildings, green buildings require construction projects to save as much energy, land, water and materials as possible throughout their life cycle to protect the environment and reduce pollution, according to an evaluation standard for green buildings released by the Chinese government in 2006.

Analysts said the move indicates that the "green construction" sector will be an economic breakthrough in terms of spurring growth and play a large role in the country's energy-saving efforts.

It will leverage a green market with trillions of yuan, as developing green buildings will effectively drive the growth of new building materials, new energy and related service sectors, said Zhang Shaochun, deputy minister of the Ministry of Finance.

The property sector possesses a strong ability to boost downstream industries. It is responsible for 50 percent of the country's steel consumption and 60 percent of cement consumption, Zhang said.

China's construction sector is estimated to account for more than 30 percent of total social energy consumption by 2020, becoming a major energy user.

But energy consumption can be effectively lowered by constructing green buildings. A preliminary study showed that an amount of energy equal to 45 million tons of standard coal can be saved by building energy-efficient buildings during the 2011-15 period, according to Zhang.

"The document indicates that the country's green construction sector is moving into a fast development phase, and shows the government's resolve to speed up energy-saving and emission-reduction efforts," said Wang Youwei, deputy head of the China Association of Building Energy Efficiency.

Wang said the room for developing energy-efficient buildings is huge, as the total combined floor area of China's existing energy-efficient buildings amounts to less than 40 million square meters.

The construction of energy-efficient buildings will be subsidized according to a three-tier grading system specified in the 2006 evaluation standard, the document said.

First-tier buildings will make their builders eligible a subsidy of 80 yuan ($12) per square meter, while second-tier buildings will qualify for 45 yuan per square meter.

The document also aimed to apply green construction standards to all government-funded public welfare projects and the low-income housing projects by 2014.

The document said more of these projects will be energy-efficient, with the goal of building more than 1 billion square meters of energy-efficient floor space by 2015.

The government will take concrete measures to strengthen fiscal support and prioritize funding to encourage the construction of green buildings in those projects, Zhang said.