New York Times: The first eco-friendly billboard is coming to Times Square, entirely powered by the sun and the wind — but there is one small catch. When there`s no sun, and no wind? The $3 million billboard goes dark: there is no backup generator. ‘We think if that happens, it`s just fine,’ said Ron Potesky, a senior marketing vice president for Ricoh Americas Corporation, the office equipment and document-storage supplier that owns the sign. The billboard — traditionally called a …