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World's tallest Passivhaus Building: The Towers of Bolueta, Bilbao, Spain


The works of the world's tallest Passivhaus residential building were designed and directed by Varquitectos architects. This 28-storey, 88-meter-high building is the first of the two towers of Bolueta, which is certified according to Passivhaus standards, which is difficult to reach in terms of energy efficiency. Until now, the tallest building in the world with these features was a student dormitory with a 26-story and 82-meter New York, Cornell Building. (1)

Passivhaus certification process

The process followed for a medium-sized building certification is as follows: Since the beginning of the project, the Passivhaus designers (Germán Velázquez and Sara Velázquez) are in the lead, who have planned the necessary measures and solutions. The Certifier and Passivhaus Institut verify the data of the building, but the certificate is only delivered when the building is finished and all requirements are confirmed.

These requirements are generally; It is verified that all data such as insulation, airtightness, ventilation time, heat losses in ventilation ducts, detailed energy consumption amounts including kitchen equipment meet the required conditions. (one)

The Towers of Bolueta projesi Passivhaus sertifikasının sahibi oldu

Thus, Passive House certificate was presented to the Project participants for the Bolueta project at the International Passive House Conference in Munich. With this highly energy efficient standard, residents will save on heating costs in the winter and enjoy a comfortably cool home in the summer. In addition, the controllable ventilation system will provide a pleasant and healthy indoor air quality. (2nd)

Sara Velazquez: "There is no turning back on the road to sustainability."

According to the traditional heating methods of the project, the new apartments, which conserve more than 75% of the heat , surpass even the future norms in Spain, which will come into force in 2019, and aim to consume almost zero energy.

In Sara Velázquez's words, “there is no turning back on the road to sustainability”: Every project is a new challenge where we try to make a building more efficient and sustainable than its predecessors: Until we find perfection, it is self-sufficient, that does not generate waste and cannot be returned to nature. to produce buildings that would not be taken. " as he describes it.

Buildings with Passivhaus certification require their heating demands to be less than 15 kWh / m2.year and their heat demand / load to be 10 Watt per square meter or less. So, for a 75 square meter house, a demand of 750 watts of heating will be enough , or in other words, using a hair dryer to heat two houses. (one)

Project details and features: (3)

Net Total Area: 45 843 m2

Number of Apartments: 361 apartments

Energy consumption: (3)

Primary energy requirement (Heat energy consumption) : 6,00 kWh / m2.year <15 kWh / m2.year

Final Energy (total consumption of all kinds of energy (heating-cooling-hot water-ventilation-lighting-electrical appliances etc.) in the whole building) : 98,00 kWh / m2.year <120 kWh / m2.year

Heat demand / load : 7 W / m2 <10 W / m2 (4)

Mechanical systems (3, 4)

Ventilation: Zehnder, Comfoair 200

Ventilation system:

* Night ventilation (Nocturnal ovarian ventilation)

* Free cooling

* Double flow heat exchanger

Heating systems: Combined heat and power systems (Gas cogeneration)

Hot water systems: Combined heat and power systems (Gas cogeneration)

Cooling system: None. (Free natural air gains were maximized.)

Renewable energy production: 60.00% (of total energy need )

Building envelope performance: (4)

Cost (3)

External wall total U-Value : 0.22 Wm-2.K-1 (Passivhaus standards glass U-Value <0.80 Wm-2.K-1, Exterior elements <0.15 Wm-2.K-1

Basement total U-Value : 0.21 Wm-2.K-1

Penthouse total U-Value : 0.21 Wm-2.K-1

Airtightness Value : 0.37 <0.60 h-1 (under 50 Pa pressure)

Construction / renovation cost: 26,000,000 € (including taxes)

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