As a pioneering entrepreneur in China's environmental protection industry, Wen Yibo is no doubt upbeat about the prospects for his company. But a major hurdle now facing the 44-year-old is how to raise capital for business expansion.

"Access to capital is a serious bottleneck constraining the growth of start-up companies in low-carbon industries," said Wen, head of Sound Group, a Beijing-based environmental protection company specializing in wastewater treatment.

"We cannot afford to raise funds in the capital markets due to investor demand for high returns, and banks are usually reluctant to lend to technology-intensive companies that lack tangible collateral," he said.