KTH, the Royal Institute of Technology has set up this new greenhouse cupola at the Berga agricultural college. I visited during the annual open-house weekend. This is a
aquaponic system. There's a fish tank in there. The water from the tank will be used to grow the tomato plants that are growing in sand.The water is cleaned as it goes through the sand and then back to the fish tank again. There are only two greenhouses like this one in Sweden today. In the future we will probably see them everywhere in the cities, up on the roofs. It is an interesting concept. No pollution from this greenhouse. The only thing added is water and fish fodder. The greenhouse will be heated by a heat exchange system, using a heat pump. The light will come from LED lamps.