Auto parts makers attending Auto Components Shanghai 2010 have called for more government support after subsidies were offered to car manufacturers for rolling out new-energy vehicles.

Most parts makers said green cars would generate more demand for related parts. But these firms are concerned about high costs that prevent green technologies from being rapidly commercialized.

Zheng Yi, accounting manager in the sales department at Shanghai Valeo Automotive Electrical System Co, said the company's restart motor, which can cut fuel use by 5 percent, costs 40 percent more than a regular engine.

"Demand for green cars may pick up next year," Zheng said. "Companies can not absorb the costs without help. If the government doesn't help, the development of green car technologies will slow."

Auto parts makers are investing in green technologies as China wants to have 500,000 new-energy cars on the streets by 2012. The government has just announced it will offer up to 60,000 yuan (US$8,785) per vehicle in subsidies to electric car makers to help cut production costs.

Zheng said his company is negotiating with car makers to share the benefits.