When Helly Scholten makes dinner, if she needs a tomato or squash or an onion, she heads upstairs–the top floor of her house is a 440-square-foot indoor vegetable garden. She starts cooking before the sun goes down, while warmth is still flooding through the glass walls of the kitchen downstairs. The entire home is wrapped in a greenhouse. Sitting on the edge of the Port of Rotterdam, Europe’s largest port–with a view of massive cranes