JINAN (Shandong) • Western countries have been looking into putting solar panels on roads for years. The Chinese have done it, installing panels on a downhill section of a highway in Shandong province.
On a smoggy afternoon, log carriers and oil tankers roared down a highway in Jinan and hurtled around a curve at the foot of a hill.
"If it can pass this test, it can fit all conditions," said Mr Li Wu, chairman of Shandong Pavenergy, the company that made the plastic-covered solar panels that carpet the road. If his product fares well, it could have a major impact on the renewable energy sector and on the driving experience as well.
The experiment is the latest sign of China's desire to innovate in, and dominate, the increasingly lucrative and strategically important market for renewable energy.
The country already produces three-quarters of the solar panels sold globally. China's leaders in solar road development are Pavenergy and Qilu Transportation.
The two companies are working together in Jinan with Pavenergy making panels for Qilu, a large, state-owned highway construction and management company that operates the highway.
The surface of these panels, made of a complex polymer that resembles plastic, has slightly more friction than a conventional road surface, according to engineering professor Zhang Hongchao at Tongji University in Shanghai, who helped develop Pavenergy's road surface.
The main Western rival to Pavenergy and Qilu is Colas, a French road-building giant that has developed 25 experimental solar roads and parking lots, mostly in France but also in Canada, Japan and the United States. Colas has been leery of putting solar panels on high-speed roads like the Chinese highway because of safety concerns. Professor Zhang, however, said the panels were completely safe.
Generating electricity from highways and streets, rather than in fields and deserts packed with solar panels, could conserve a lot of land. Those advantages are particularly important in heavily populated China, where demand for energy has risen rapidly.
And because roads run through and around cities, the electricity could be used practically next door to where it is generated. That means virtually no power would be lost in transmission.
Solar roads could also change the driving experience.
Electric heating strips can melt snow that falls on them while light-emitting diodes embedded in the surface can provide illuminated signage to direct drivers and alert them to traffic hazards.
Such roads are finally becoming viable. Thanks in large part to soaring Chinese production, a solar panel now costs a tenth of what it did a decade ago.
Still, a litany of outstanding challenges means the wide deployment of solar roads is a long way off.
For one, they are less efficient than rooftop solar panels at converting the sun's light into electricity.
Solar roads are also more expensive than asphalt. It costs about US$120 (S$160) a sq m to resurface and repair an asphalt road each decade.
By comparison, Pavenergy and Colas hope to be able to bring the cost of a solar road to US$310 to US$460 a sq m with mass production.