After standing dormant for 34 years, the Bankside Power Station was reborn last month. The onetime oil-fired, soot-spewing electric power plant, shut down and then converted into the Tate Modern, the world’s most popular contemporary art museum, is back producing energy again. Its roof has been coated with solar panels, which soak up the sun’s rays even on a cloudy London afternoon and help illuminate the avant-garde works in the galleries below. But rather than a shiny vision of modernity, the solar installation may become a sad remnant of a lost future. […]