The prototype pavilion consists of 17m-tall steel cylinders (using 80% recycled steel), with inner surfaces overgrown with ivy. At the top, funnels draw air into the cylinders. When temperatures reach 27°C, ventilators activate and propel the air down into the cylinders and through dampened cellulose panels, creating a cloud of water vapor and reducing the temperature of the falling air by 8-12°C. The pavilions therefore offer both shade and cool air. Because the design functions best at high temperatures and low humidity, it is ideal for – and transferable to – most Mediterranean cities. The designers expect the temperature under the pavilion to be 10-15°C cooler than the surrounding area.

Benefits

The pavilions are quick to assemble, and reassemble; they are low maintenance; they can be planned to fit in with the urban environment; and other features such as energy-efficient lighting can be incorporated. The prototype pavilion in Madrid also has symbolic value that should not be underestimated. The Ecological Boulevard establishes a landmark and reference point in the newly-developed area, creating a sense of place and identity. The air tree pavilion with its futuristic look achieves this – it has been given names locally like “el arbolito” and “the rocket”.

Installed as temporary supports, the air-trees will be used only until air-conditioned spaces are no longer needed, when the area becomes “fixed”, and trees within the concourse are fully established. When a sufficient amount of time has passed, these devices should be dismantled, leaving remaining spaces that resemble forest clearings. The air tree is a light structure, easily dismantled and energetically self-sufficient, that only consumes what it is capable of producing by means of systems designed to capture and use solar photovoltaic energy.

Project progress

All three pavilions of the project have now been built:

• Air Tree: a light structure, easily dismantled and energetically self-sufficient, that only consumes what it is capable of producing by means of systems designed to capture and use solar photovoltaic energy.
• Media Tree: an open structure to multiply resident-selected activities. Installed in the non-city as temporary prostheses, they will be used only until air-conditioned spaces are no longer needed, when the area becomes “fixed”.
• Lucid Tree: these light features shall be dismantled after the urban fabric strengthens, leaving remaining spaces that resemble forest clearings.

From Madrid to Shanghai

The success of the project is currently featured in the Madrid Pavilion of the Shanghai Expo. The “Air Tree” with its different technical layers supports multiple final configurations and a myriad of intermediate positions (opaque, translucent, transparent, bright, interactive, open, etc.). Different textiles for video projections allow an unlimited combination of scenarios adaptable to the needs of visiting citizens. Its appearance can be transformed over the daily cycle, as well as monthly throughout the year. By sensors it is connected in real-time with the climatic conditions of Shanghai, constantly adopting the optimal physical configuration and energy consumption to generate climatic comfort for the citizens.

Ventilation inside the Air Tree is provided through a big fan of 7.3m diameter, suspended by a tensegrity structure in the center of the space, at a height of 11.5m. Through a telescopic system the fan can be lowered several meters to be located closer to the visitors. The exact position and speed at each moment is determined according to the climatic conditions of the environment that are monitored continuously in the surroundings of the structure.

Project background

This focused on the development of a bioclimatic design of a boulevard in Madrid’s metropolitan periphery with an approach that is functionally flexible in enabling programmatic variety, yet the formal expression is architecturally specific. The project received funding from the European Commission “LIFE 2002” - Environment (ENV/E/000198) program for urban development innovation.

The project sought to contribute to the environmentally and socially sustainable urbanization of the UE1 sector of Vallecas in Madrid’s south-east. Conventional urban planning for the boulevard that forms UE1’s main axis would have led to a solution typical for many recent residential areas in Madrid’s outskirts: a 550m long and 50m wide stretch of pavement and poor vegetation, symmetrically lined by two-lane traffic and parked cars, bordered by 17m high residential building blocks and exposed to wind, dust and summer temperatures that can peak at 40°C.

The objective was to evoke the Mediterranean spirit of outdoor public life through a contemporary urban design project for an open space in the newly developed district of Madrid. Ecosistema Urbano proposed to line a semi-pedestrianized boulevard with pavilions that would act as “air trees”, providing shade, ventilation and vegetation, whilst functioning as “social activators” - bringing people outdoors – in the yet-to-be-built neighborhood.