Guess where Asia's fastest-growing clean tech industry is

China's commitment to a greener future has been cast into the spotlight this week as heavy smog engulfs its capital city, spawning puns from 'Grayjing' to 'Airpocalypse,' but new data offer proof of the mainland's dedication to clearer skies.

China boasts the higher number of fastest-growing clean technology companies in Asia-Pacific, according to a new Deloitte report released on Thursday.

Every year, Deloitte ranks the 500 fastest-growing technology, media and telecommunications firms across the region based on percentage revenue growth rates. This year, clean technology was the third leading industry with more than 48 companies on the list, out of which 27 were Chinese.

The results come as President Xi Jinping reaffirmed Beijing's dedication to reducing greenhouse gas emissions at a closely-watched climate change conference in Paris this week. He also stressed any agreement inked at the summit should respect the rights of developing countries to grow their economies as they continue to industrialize.

"China shines in clean energy," Paul Sallomi, Deloitte's vice chairman and global technology, media, telecommunications industry leader, told CNBC.

While it will take a long time for the nation to see clearer skies following decades of industrialization, the government's environment policies are encouraging, he said.

Beijing has pledged to reduce carbon intensity by 60 to 65 percent by 2030 compared to 2005 levels, a goal it submitted to the United Nations ahead of this week's summit. On top of that, President Xi Jinping's administration is also widely expected to unveil new measures aimed at curtailing carbon emissions and support the development of renewable energy.

"There are three critical ingredients to a cleaner future: the regulatory environment, incentives regulators provide for the developer community to innovate and the innovators themselves," Sallomi noted.

"I think China has more tools than California did when it started on the same journey 30 years ago."

Indeed, the world's second-largest economy has deep pockets when it comes to funding its ambitious climate targets, having spent more than $90 billion on low-carbon energy last year, nearly double the U.S.'s $50 billion spend, according to think-tank World Resources Institute.

Deloitte's report also cemented China's role as Asia's overall tech leader. The mainland dominated the rankings geographically, with 139 companies on the list and six in the top ten.

South Korean gaming firm Devsisters was ranked Asia's fastest-growing tech firm, followed by Chinese hardware maker Wuhan Hi-Target Digital Cloud Technology and Australian software company Prospa. The top 500 names this year averaged a revenue growth of 415 percent, higher from last year's average growth of 405 percent.

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