It's no exaggeration to say that Renzo Piano is one of the most unanimously respected architects in the world of architecture. With an oeuvre that blends respect for context, lightness and technology to create environmentally conscious and aesthetically pleasing structures, his approach combines advanced materials with traditional techniques. In projects of various scales, the Genoese architect maintains an essential thread: the implementation of passive architectural strategies, highlighting the importance of these methods for sustainability and energy efficiency. This is often made explicit in his sketches, as an initial concern, and clearly comes through in the finished works. Here are some examples of iconic projects developed by his office in recent decades.
The Shard, London
One of Piano's most famous projects, this skyscraper incorporates passive design elements along with a number of engineering feats. The building features a double façade, which improves natural ventilation and reduces the need for artificial cooling. This outer layer of glass allows solar gain to be controlled, while the inner layer provides thermal insulation, significantly reducing the building's energy consumption. The façade also has an intelligent blind control system that dynamically adjusts throughout the day, ensuring that they are only used when and where necessary, optimizing the balance between natural light and thermal comfort. This maximizes the entry of natural light, reducing dependence on artificial lighting and improving occupant comfort.
A unique aspect of The Shard's design is the fact that the outer glass panels do not meet, leaving spaces between them. These spaces facilitate the constant flow of air around the building, naturally regulating the internal temperature without the need for extensive mechanical ventilation systems. Some floors also incorporate winter gardens, which are naturally ventilated through strategically placed openings. These act as thermal buffers, improving the building's insulation and providing pleasant, naturally lit spaces for occupants. Natural ventilation in these areas reduces the need for mechanical cooling, contributing to the building's overall sustainability.
The project also uses an innovative approach for heat management. The excess heat generated by the office spaces is reused to heat the hotel and apartment spaces within the building, minimizing energy waste. Any excess heat that cannot be used is naturally dissipated through a radiator located at the top of the building, preventing overheating and maintaining a balanced internal climate.
California Academy of Sciences, San Francisco
The project for the California Academy of Sciences in San Francisco is another example of the innovative use of passive design strategies and energy efficiency systems. Large glass windows and skylights strategically placed throughout the building maximize natural lighting and improve cross-ventilation, without allowing the entry of direct sunlight during the hottest months of the year. Overall, 90% of the occupied spaces have access to natural light and external views. Another element is the iconic landscaped slab, covered with native plants, which provides natural insulation and reduces the urban heat island effect. It also facilitates rainwater collection, promotes biodiversity and prevents rainwater runoff from carrying pollutants into the ecosystem.
Another important component is ventilation. The museum's central plaza is under a huge glass roof that opens at night to allow fresh air into the building. On the main public floor, an automated ventilation system takes advantage of Golden Gate Park's natural air currents to regulate internal temperatures through louvers on all four sides of the building. These open and close throughout the day and night, providing fresh air and cooling the building. The museum also uses underfloor heating, a key component of its energy efficiency. Pipes embedded in the concrete floors carry hot water, heating the spaces where people move around. This system reduces the building's energy needs by around 10% annually.
Tjibaou Cultural Center, New Caledonia
The Tjibaou Cultural Center is an exemplary model of passive design adapted to the local climate; in this case, that of an island in the Pacific Ocean. Inspired by traditional Kanak huts, the project uses natural ventilation through strategically placed openings that promote airflow. The orientation of the buildings and the use of local materials further enhance their environmental harmony and energy efficiency. The project is located on a narrow peninsula near Noumea, with the museum's ten wooden volumes located on the bay side, their curved façades facing the prevailing sea winds. Noumea has a climate considered “oceanic tropical,” hot and humid, in which the incorporation of efficient passive cooling systems can be achieved through ventilation, microclimates and shading devices.
The project is located on top of a hill to maximize natural ventilation, where it can take advantage of the winds from the south. The lack of trees on this side of the island makes it easier for the wind to enter, while tall trees on the east and west sides channel the wind into the project. Ventilation acts as passive cooling, complemented by fresh air generated by the temperature difference between the land and the surrounding water. In addition, two principles are used for natural ventilation: the chimney effect and wind forces. The air circulates between the pieces of wood, with a double panel system that brings in breezes or guides convection currents. The outer shell directs these currents with its design, while the inner skin has horizontal louvers at the base and below the roof. The upper louvers are fixed to balance the pressure, preventing damage to the roof, and the lower ones are adjustable according to the direction and intensity of the wind, also acting as shading for solar control.
The Whitney Museum of American Art at Gansevoort, New York
The Whitney Museum of American Art, located in New York's Meatpacking District, incorporates strategies that improve its environmental performance and sustainability, while providing a comfortable and dynamic space for art exhibitions and visitors. In terms of natural ventilation, the building has several operable windows, which allow fresh air to circulate throughout the spaces, reducing the need for mechanical cooling systems. The museum was also designed to maximize the use of natural light, and strategically placed large windows and skylights allow daylight to penetrate deep into the interior spaces. This reduces the need for artificial lighting during the day, lowering energy consumption and providing a more pleasant, naturally lit environment for viewing art. The design of the windows also includes external shading devices that prevent excessive heat gain, minimizing the cooling load.
The museum also features several outdoor terraces designed not only for aesthetic and functional purposes, but also to contribute to the building's environmental performance. These include green roof elements that provide natural insulation, reducing heat gain in summer and heat loss in winter. The building envelope was designed with high-performance glazing and insulation materials to minimize heat transfer. The glazing reduces heat gain while allowing natural light in, and the insulation helps to maintain consistent interior temperatures, improving energy efficiency.
Padre Pio Pilgrimage Church, Italy
The Padre Pio Pilgrimage Church, located in San Giovanni Rotondo, Italy, is renowned for its organic and innovative design, incorporating several passive strategies that improve its environmental performance and create a serene and contemplative atmosphere for visitors. Firstly, the church makes extensive use of thermal mass to stabilize internal temperatures. The thick stone walls absorb heat during the day and release it slowly at night, maintaining a consistent and comfortable internal climate. This passive thermal regulation reduces the need for active heating and cooling systems, thus reducing energy consumption.
Piano's design strategically incorporates natural light to enhance the spiritual experience and reduce dependence on artificial lighting. It features carefully positioned skylights and openings that allow natural light to penetrate deep into the interior spaces, which also create a dynamic play of light and shadow, enhancing the aesthetic and spiritual environment. Light wells are used to direct sunlight to specific areas, creating focal points of light that highlight the main architectural and religious elements of the church. In addition, vertical ventilation shafts are integrated into the design to encourage warm air to rise and escape, while cooler air is drawn in at lower levels, creating a natural ventilation cycle.
Renzo Piano's architectural masterpieces demonstrate how passive design strategies can be effectively integrated into large-scale projects to increase sustainability and energy efficiency. By employing them, not only is the ecological footprint of his buildings reduced, but functional and inspiring spaces are created that serve as exemplary models for future architectural developments, showing the profound impact of intelligent and sustainable design.
This article is part of the ArchDaily Topics: Passive Architecture. Every month we explore a topic in-depth through articles, interviews, news, and architecture projects. We invite you to learn more about our ArchDaily Topics. And, as always, at ArchDaily we welcome the contributions of our readers; if you want to submit an article or project, contact us.
