China's economy might be No 1 in 2030

"There is a danger of underestimating the strength of the US economy and its ability to innovate. It will probably begin to grow again by 3 or 4 percent or even higher. If that happens and China slows down, it is going to take a while to catch up."

Duncan Innes-Ker, senior China analyst for the London-based Economist Intelligence Unit, argues that there would have to be significant improvements in China's business environment before China could make such a rapid advance.

"There needs to be major reform of the legal system and regulatory environment to put China on a level with developed countries."

He believes the Chinese economy faces significant future headwinds, particularly with its labor force shrinking by 11 percent from 798 million in 2013 to 718 million in 2030. He expects China to catch up with the US by 2023; but as to when it is double the size, he said is out of his forecasting range.

"Growth won't be easy in the coming two decades and I expect it to slow to 3.7 percent in the 2020s as the labor force shrinks. China has experienced the classic catch-up when it was easy to grow by just catching the low-gathering fruit. It now needs to up its game."

In China 2030, Hu takes the view China's State-owned enterprises, which dominate the major sectors of the economy, are a strength and not a weakness. He points out that 64 of the Fortune 500 companies are now Chinese State-owned enterprises and remain a driving force of the economy.

But Xu Bin, professor of economics and finance and associate dean at CEIBS in Shanghai, insists China's SOEs are actually a barrier to growth and that many ought to be privatized.

"There is little doubt that the success of the Chinese economy will be closely associated with the reform of the State-owned sector. Without a vigorous private sector, there is no future for the Chinese economy.