Reuters: Exelon Corp, the largest nuclear power operator in the United States, on Monday became the latest U.S. power company to say it will leave the Chamber of Commerce over that group’s opposition to the climate bill. “The Chamber and other groups think climate legislation will be bad for the economy,” an Exelon spokeswoman said. “We think it’s going to be good for the economy.” Exelon’s top executive John Rowe said in a speech on Monday that the company would not renew its …