US Energy Secretary Jennifer Granholm got an up-close look at the opportunities of offshore wind power on a ferry tour of the Block Island wind farm Friday, then discussed the challenges the industry faces at a roundtable discussion at a Quonset Development Corporation building here. “It’s such an amazing time, and we cannot squander it,” Granholm said at the roundtable. “I keep saying your hair has to be on fire.” Rhode Island, she said, is doing that. “Your hair is so on fire, you have a hat on,” she told the state’s acting energy commissioner, Chris Kearns, who was wearing...