U.S. companies are hustling down to Mexico to build power plants to supply energy-starved California, and Mexican environmentalists aren’t happy about it. Mexican officials and the power companies say that the economic benefits of the new plants will outweigh the pollution they add to the air. Alejandro Calvillo, director of Greenpeace Mexico, counters that the environmental costs are unacceptable and the U.S. has no right to export more of its dirty industry problems to Mexico.