Showa Shell Sekiyu K.K. is considering selling shares in a solar-panel unit to fund an expansion of its renewable energy business and cut reliance on fuel sales.

Shares in Showa Shell Solar K.K. may be sold either in Japan or overseas, Chairman Shigeya Kato said in an interview in Tokyo on Monday. The funds may be used to build a fourth factory, probably in the Middle East, to make panels that convert sunlight into electricity, he said. Kato didn't say how much money may be raised or when the proposed initial public offering may be held.

The unit of Royal Dutch Shell PLC aims to enlarge its share of the global solar-panel market to at least 10 percent by March 2015 from the current 1 percent, and diversify from refining as Japan's petroleum demand declines because of its shrinking population and increased energy conservation.