>Not even fans to move the air around? Only in the hottest days when all room were occupied, as I no longer live there with my siblings, they no longer have fa

>Not even fans to move the air around? Only in the hottest days when all room were occupied, as I no longer live there with my siblings, they no longer have fans there. There was one bath-vent-like-fan before. >fully passive systems are awesome - though not always easy or possible. I wouldn't install this in the UK as gardens are tiny, full of concrete and air humidity is high. Works well in central Poland. >or larger loads, your exchanger will need to be large and buried deep. This might be another factor limiting application in cities. yes, you need trees around, and grass not concrete or bricks.