Toyota Motor Corp. said it was planning to sell around 15,000 of its hybrid-powered Prius models overseas next year, with the bulk of them going to North America. The Prius was the first mass-market hybrid-power car, going on the market in Japan in 1997. Hybrid-power cars combine a traditional gasoline engine with an electric motor to offer greater fuel efficiency and lower emission levels than conventional cars. The Prius will go on sale in the U.S. in July, with sales in Europe beginning in September. Pricing will be around $20,000.