A national legislator has called for more preferential policies to help further tap the potential of hydrogen as China makes its low-carbon transition.

Aside from using the clean energy source as fuel for more types of vehicles and industries, measures should also be rolled out to have more of the gas utilized as a byproduct in some industrial sectors, said Zhang Tianren, a deputy to the National People's Congress.

Recognizing hydrogen as an energy that could help reduce carbon emissions, bolster energy safety and help stimulate economic development, many countries have been striving to develop the gas, according to Zhang.

By the middle of this century, hydrogen will create 30 million jobs and eliminate 6 billion metric tons of carbon dioxide emissions globally, he said, quoting a prediction from the Hydrogen Council. The council is a collaborative group consisting of energy, transport, industry and investment companies worldwide.

The production value of the hydrogen sector around the world by that time should be about $2.5 trillion, he added.

Zhang, who is also of chairman of the Tianneng Group, one of China's largest battery manufacturers, also stressed the great potential of hydrogen development in China.

According to the White Paper of Hydrogen Energy and Fuel Cell Industry in China, the production value of hydrogen industry will jump to 12 trillion yuan ($1.9 trillion) by 2050, he noted.

However, he also pointed out some problems that will hinder hydrogen from having a stronger role in the country's energy production efforts, and he called on the government to hammer out preferential policies accordingly.

"The country still lags in terms of core technologies and equipment for hydrogen energy development and hydrogen fuel cells," he said.

Zhang noted the "slow-paced" development of hydrogen fuel cell vehicles and a lack of policy support to extend the application of the gas to other sectors.

By the end of last year, the number of new energy vehicles across the country had reached 7.84 million, he said. Of those vehicles, however, only 8,400 were powered by hydrogen fuel cells.

"The hydrogen fuel cell vehicle industry is still in its early stages of development," he said. Lured into the market because of preferential policies and subsidies, companies have yet to make adequate investment into research and development of such vehicles.

Hydrogen is an alternative energy for some major carbon emitters, including the inland shipping, railway, chemical and smelting industries, he said. With no preferential policies in place, however, hydrogen hasn't been used much in these sectors.

Hydrogen is used as a byproduct in some industries, but in general such byproduct is simply discarded.

The production of 1 ton of caustic soda, for example, will usually generate nearly 23 kilograms of hydrogen as a byproduct. About 30 percent of that byproduct is discharged without being collected for utilization, he said. This means that roughly 300,000 tons of the gas was wasted in the caustic soda industry in China last year.

Zhang called for more efforts to collect such byproduct. He said the collection will not only reduce the cost of producing hydrogen but also make mass production of the gas possible.