The wind blows over the whole world and everywhere the local building tradition has developed methods in the course of time to protect against the negative effects of the wind. But protection against the wind is only an important design factor in areas with high wind speeds, in the more moderate areas it is more of a friend than an enemy. For centuries the wind has been used to generate energy and to cool and ventilate buildings in a natural way. A lot of those traditional techniques were left unused after the industrial revolution. The last decades they return in several forms.
The
energy of the wind can be used, by means of windmills, to drive tools
that for example grind grain or pump water. Nowadays it is no longer necessary
to directly use this energy, which can be converted into electricity,
transported and temporarily stored. Windmills come in many forms, but
nowadays they are often very big to efficiently generate energy. Besides
a few interesting exceptions, they therefore (still) don’t play a
roll in the current architecture.
The wind can be used to create airflows in a building and with that make natural ventilation possible. The best known traditional example is the wind towers of Hyderabad, that rise above the buildings and brings fresh air in the buildings by means of openings that are directed to the wind. Especially in areas with a dominating wind direction the power of the wind can be used as a ventilation motor. By using the lower pressure area that is created as the wind blows along a building, air can be sucked from the building. Even lower pressure can be achieved by letting the wind blow along a curved roof or façade.
But even if the external wind isn't used, then air transfers within the building must still be stimulated. The air must be refreshed and in many circumstances air is used as a means to spread heat or coolness through the building. For years that was achieved by mechanical means, but that isn’t necessary. By using temperature differences and by using the characteristic that warm air rises (the chimney effect) an airflow for ventilation, heating and/or cooling can be started. The knowledge about this so-called natural ventilation is old, even the termites know about it. With modern measuring- and research techniques the airflow can be controlled better and better. We relearn how to play with the wind.
pv