A Princeton civil and environmental engineering student has a vision for an environmentally sustainable building which takes adaptive architecture to the next level through the development of a shape shifting façade.

Denisa Buzatu is designing and prototyping a structure that shades the façade of a building by folding and adapting its shape in response to sunlight. She describes it as ‘electrical origami.’                

The design makes use of a seamless surface comprising eight individual triangle pieces. Along the edge of each triangle is a wire that contracts when current is applied but returns to its original shape when the current is cut. Each wire can be activated individually or collectively by a microcontroller, enabling the surface to fold in hundreds of different formations.                       

The overall shape of the structure is incredibly flexible, yet the individual parts are rigid. This allows them to be composed of any material, from acrylic to solar panels.

By integrating a combination of solar panels and sensors that monitor the amount of sunlight hitting a building, the modules will flatten automatically during sunny periods to simultaneously collect energy and shade the structures. Using a small part of the collected energy, the module then folds away when the sun is shrouded by clouds.

origami“The overall goal has been the design of a structure that is architecturally pleasing while also practical from a structural and environmental point of view,” said Buzatu.

In the United States, buildings account for about 40 per cent of all energy usage, including 75 per cent of electricity use. In Australia, households currently spend approximately $15 billion per year on electricity and gas bills.

“If adaptive architecture technology is integrated into buildings as they are being designed, it has the potential to cut the energy consumption of buildings in half,” Buzatu said.

Currently, most adaptive architecture technology and approaches rely on complex mechanical systems to enable shape transformation. This can be difficult to build and expensive to maintain. Buzatu’s folding face and microcontroller approach is simpler while being sustainable and energy efficient.

As fixed shading devices are only effective for at best half of the day, the rest of the time they block out valuable daylight. The cost to construct them in terms of time and resources can be extensive, so there is financial as well as environmental incentive for adaptive façades. This can be assessed using whole building energy modeling.

“This is a fairly complex process, however, when responsive components are involved, as is the case here,” said Mathieu Meur, managing director of Meinhardt Façade Technology. “Also, project-specific models need to be developed, as each building is different in terms of mechanical equipment, façade design, building shape and orientation, operating schedule, occupancy, internal electrical loads and heat sources, all of which affect the overall building energy consumption.”

There are a number of past and current efforts in adaptive architecture of varying success.

For instance, there are a number of revolving houses built in Europe, where a house's angular position is adjusted to make the most of available sunlight and heat in winter, and to minimize heat load in summer.

Designer Patrick Marsilli’s revolutionary solar structure, for example, also includes optional integrated solar panels to store energy as well as several possible ecological options for better energy efficiency.

revolv04The Institut du Monde Arabe in Paris, designed by Jean Nouvel and completed way back in 1980, also includes a prominent adaptive façade with a series of metal irises that open and close automatically using photosensors to regulate the amount of light penetrating the building envelope.

facade - move1“Another possible reference, closer to the approach suggested by Buzatu, would be the Al Bahar Towers in Abu Dhabi,” said Meur. “This building façade features large folding sunshades (in the semblance of traditional Arabic mashrabiya), the position of which can be individually controlled to optimize the amount of light and heat entering the building.”

The screen reduces solar gain by around 50 per cent and reduces the building’s need for energy-draining air conditioning.