Green Bioclimatic Towers

Lisbon (Portugal)

Housing Cooperative “Viver a Luz”


Built between 1998-2002


Leading case typology

   Leading case function



   Industrial, services, etc.

Main Results

  • A 50% superior environmental performance to current practice achieving a class A on the LiderA certification system (Portuguese voluntary system for assessment of sustainable construction);
  • The contribution of solar energy for DHW (Domestic Hot Water) accounts for approximately 16.6% of the total energy consumed and 30.34% of other energy consumption (gas and solar) and 60% of the energy required for hot water heating.

Built on the assumptions of sustainability and energy efficiency, the Green Towers are a demonstrative residential complex that set up ambitious targets of thermal comfort levels, by adopting building energy efficiency and by using renewable energy systems.

Project Details

Green Towers are a residential complex with bioclimatic features and innovative design solutions. It is located at the north area of Parque das Nações in Lisbon, the global area of Expo 98 Lisbon World Exposition. The project is composed by two pioneer’s bioclimatic towers, with a 35.112 m2 built gross area, where the detailed urban plan created very favourable conditions to the bioclimatic architecture design adopted.

The idea for this project was to design a demonstrative residential complex at national and international level, able to achieve high levels of thermal comfort throughout the years, by adopting building energy efficiency measures and by using renewable energy systems.

The first tower was built in 1998 with 41 apartments and approximately 7.200 m2 of building area assembling a set of optimized energy-environmental measures was also made possible by grant Thermie 96 program, provided to the incorporation of solar passive and active technologies.

In 2002, was built the second tower designated South Tower with 55 different typologies apartments. It was designed with the integration of passive solar technologies and thus counted with EU support under the Altener II program, a community program that promotes the implementation of renewable energy in European member states.

The experience obtained on the first green tower contributed decisively to the program definition for the South tower, allowing the introduction of new solutions and taking further what was posted on the first green tower successfully.

Both projects were a solid commitment in the application of bioclimatic principles, especially through the application of passive means. The careful use of materials adapted to the use conditions, contributed simultaneously to the environmental performance of the buildings and constituted an important step to enhance the concept of rationalization of energy consumption in buildings.

To evidence it, the two buildings were subjected to a built environment assessment conducted by the LiderA (Portuguese voluntary system for assessment of sustainable construction) system to undertake an evaluation of each built environmental performance level: integration site; resources; indoor environment; environmental management and innovation.

The towers are situated in an urban redevelopment context which aimed to recover a riverside area previously industrialized and widely polluted, thus ensuring a full recovery and enhancement of the entire local site area, as an excellent measure for the integration site criteria.

In terms of energy resources and due to the implementation of bioclimatic measures, it was provided an excellent passive energy profile that results in an effective reduction of total electricity consumption (average electricity consumption stands at 26.49 kWh/m2.year), satisfying the criteria of quality and comfort indoor air. Besides minimizing the consumption of electricity solutions aimed at maximizing the contribution of renewable energies to other uses, the contribution of solar energy for DHW (Domestic Hot Water) was about 9.72 kWh/m².year, accounting for approximately 16.6% of the total energy consumed and 30.34% of other energy consumption (gas and solar) and 60% of the energy required for hot water heating.

Some measures designed to ensure the quality of the indoor environment were also implemented through the existence of almost exclusively natural ventilation solutions. Thus, thermal comfort is one of the most outstanding aspects of these buildings, having been founded the satisfaction of the ASHRAE (American Society of Heating, Refrigerating and Air Conditioning Engineers) thermal comfort parameters, either in heating or cooling seasons.

In terms of environmental management it was constituted a user’s guide with instructions of equipment operation, maintenance and awareness (reduction and separation of waste, encouraging the use of low-consumption lamps) and it was implemented a monitoring plan to check the inner conditions of temperature and humidity, and also for energy consumption, allowing the fact that the conditions for thermal comfort are ensured.

This evaluation determined the attainment of class A under the LiderA classification system, which came to prove their superior environmental performance compared with current building practice.

Both projects have already collected a set of prizes, including in 1997 the “best development complex of 1997 – urban planning and environment” annual rewarded by the real state magazine, and in 2000 another award (Green Project Award) given by the real state magazine was attributed specifically to the South tower.