Agence France-Presse: Japanese trading house Sojitz Corp. is planning to enter the solar power generation business through a 100 million dollar investment in a US firm, it was reported Thursday. Sojitz will take a minority stake in California-based Solar Power Partners Inc. The third-largest US solar power developer plans to build up to 10 solar farms by 2015, the business daily Nikkei reported. The move comes as the US solar power generation market is expected to grow by 40 percent under President …