The power shortages spawned by the Tohoku quake and tsunami are expected to continue this summer and maybe even longer, leaving companies whose production lines are already affected unsure how they will cope in the long term.

Renesas Electronics Corp., a major semiconductor maker, has production sites in Takasaki, Gunma Prefecture, and Kai, Yamanashi Prefecture, that have not been able to operate due to the power outages implemented by Tokyo Electric Power Co.

"For the wafer treatment process, a 24-hour electricity supply is generally needed," said Renesas PR officer Makie Uehara.