JOIN US TONIGHT (Tuesday night) on the WGN NEWS at 9PM--We take you to the Byron Nuclear Power Plant and look at the rising demand for electricity in the years ahead Illinois leads all other U.S. states in the percentage of electricity generated by nuclear power. Anywhere from 50 to 80% of the Chicago area's electricity comes from nuclear depending on the day and time of year--and that's been true for years. In fact, the first nuclear power plant in Illinois--the Dresden Generating Facility near