China, the most coal-reliant country in the world, will face a few hard decades to raise its clean energy to 50 percent by 2050 but the prospects are good, a senior climate change expert said on Monday.

Among a diversified package of energy solutions, nuclear power will play a key role in the long term, which is expected to account for about 15 percent of China's energy consumption by 2050, according to Du Xiangwan, chairman of China's National Climate Change Expert Commission.

"The country will face a critical transformation period in the next 20 to 40 years," Du said in an exclusive interview with China Daily.

China must explore multiple solutions in addressing its energy issues, given the vast size and population of the country, he said.

China remains the largest coal consumer in the world, with more than 70 percent of its consumption dependent on coal.

China's GDP growth has held steady at about 10 percent for many years - in which 3 to 4 percent was created at the expense of the environment, he said.

"It's the country's urgent inner demands to transfer to clean energies (and) we need economic growth, but at a high-quality level," Du said.

Although this undertaking would be long and strenuous, Du said he was "optimistic".

Nuclear energy is deemed as one of the most important solutions for China's energy challenges.

Du, who is also the director of the nuclear science and technology institute at Peking University, said that the most important precondition regarding nuclear security and radiation issues have already become controllable.

China currently has 28 nuclear reactors under construction - more than the world's total being built.

Besides aggressive efforts in China, the country has taken part in International Thermonuclear Experimental Reactor, an international project to design and build an experimental fusion reactor based on the "tokamak" concept. Nuclear fusion is considered the energy of the future.

"Nuclear will be one of the key energy pillars and is designed to account for about 15 percent of China's energy consumption by 2050," Du added.

China will increase its nuclear power capacity by 70 to 80 megawatts by 2020 - at which time nuclear power will increase from its current level of about 1 percent to some 4 percent in energy supply.

The country, so far, has made great progress in equipment manufacturing, and has attached great importance to cultivating talent.

More than 40 Chinese universities, for example, graduate young students majoring in nuclear power and engineering.

Natural gases - which are relatively cleaner compared with coal and oil - will have great potential in China and are expected to reach 10 percent by 2050, Du said.

These include conventional natural gases and also coal-seam gas, shale gas and gas hydrate, Du added.

However, China has a long way to go in achieving technological breakthroughs to reach a commercial scale, he said.

Efforts including a national smart grid development and energy efficiency enhancement in rural areas are also important elements.

Agenda for 2011-2015 China is considering putting climate change legislation on its legislative agenda during the 12th Five-Year Plan period (2011-2015), said Xie Zhenhua, the country's top climate officer. The country already has a set of laws and regulations related to energy conservation, renewable energies, environmental protection and so on, said Xie, who is also the deputy director of China's National Development and Reform Commission. During the next five years, incentives, taxation policies and market tools will also be adopted to help reach the country's binding targets on carbon intensity, non-fossil fuel consumption and forest protection. China has already set up several environmental exchanges in Beijing, Shanghai and Tianjin, where some pilot carbon offset programs are already under way, according to Xie. The Standing Committee of the National People's Congress has already passed a resolution on combating climate change in August 2009. According to the resolution, China will adhere to "the basic framework" set up at the UN Framework Convention on Climate Change (UNFCCC), signed by more than 150 countries in 1992 - and the Kyoto Protocol, agreed on in 1997 by most of the international community, setting binding targets for developed countries to reduce carbon dioxide emissions, along with the principles of UNFCCC-endorsed "common but differentiated responsibilities". ???????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????? Li Jing