Detail from Piero della Francesca’s “Virgin and Child Enthroned with Four Angels” In the hometown of Renaissance painter Piero della Francesca, the Tuscan borgo of Sansepolcro, the Kilowatt Festival, in its 20th year, examines how contemporary performance can foster “urban regeneration.” This year’s theme, “Excess of Reality,” entrusts performance with reformulating “a forgotten ethic of ...