Reuters: Japanese oil distributor Showa Shell Sekiyu KK plans to build one of the world’s biggest solar panel plants as it seeks new revenues amid weak gasoline sales, a source close to the matter said on Wednesday. Showa Shell is considering a plan to spend roughly 100 billion yen (US$943 million) to build a solar plant with an annual capacity of 1,000 megawatts, said the source, who spoke on condition of anonymity. The plant, to go online in 2011, would be equivalent to solar …