High hopes have been pinned on Chinese consumers, whose potential purchasing power is deemed crucial to future global economic growth, even as many of their counterparts in rich countries are now busy reducing spending and paying off debts.

Yet, before China can transform itself into a consumer society, how it invests and produces will continue to matter more to global growth than how it consumes.

Fortunately, the rapid growth of Chinese investment in clean energy indicates that the world's fastest-growing major economy is becoming, perhaps somewhat surprisingly, the champion of green growth.

For those developed countries that have been reluctant to shoulder their due responsibilities in combating climate change, citing inadequate efforts from developing countries, they should take a look at a recent report by Ernst & Young which shows that China has overtaken the United States as the most attractive market for renewable energy investment.

According to the report, in the second quarter of 2010 alone, China spent about $10 billion on wind energy, or about half of the global total of $20.5 billion.

Though such a quarterly investment in wind power barely makes a dent in the huge energy-efficiency gap that exists between China and developed economies, it is still an impressive testament to the country's determination to go green.

As the world's most populous country, China is fully aware of the imminent energy and environmental challenges it faces. The country's per capita energy consumption is only one fourth of the US, but no Chinese policymaker has ever considered it a policy option to allow energy consumption to grow to the level it is in the US.

With an average per capital income equal to about one tenth that of rich nations, China has decided to do its utmost to embrace a low-carbon future. To help cut carbon emissions per unit of GDP by up to 45 percent of 2005 levels by 2020, China is trying to develop renewable and nuclear energy with the goal of increasing the share of non-fossil fuels in total primary energy consumption from 7.8 percent in 2009 to 15 percent by 2020.

It is such government enthusiasm to go green that has enabled China to surge ahead of the rest of the world in renewable energy.

Some Western companies, which for most of the past decade enjoyed a leading position in clean technology, will no doubt have been shocked by the rapid progress made by their Chinese counterparts. But instead of complaining they should ride on China's green investment boom while urging their own governments to elevate and fulfill their commitment to a low-carbon future.

Massive green investment is essential to any global deal to effectively fight climate change. And the world simply cannot afford to postpone pursuing green growth, no matter what negotiators in Cancun come up with. China has already made that commitment. Will rich countries do so too?