When I was in Germany about 100 years ago - ok the 80s - they had metal shutters that rolled down to cover the windows. The shutters were outside but could be controlled from the inside. The could be closed tight, cutting off all light/most of the air, or left slightlty open, letting in some light and air. Even in the almost closed position the window would still be covered from weather damage.

Never saw them before or since, but think I would get some for the house if I needed them / could figure out where to get them.