Office Building, LEED Silver
Hydronic System – Ground Water
LEED Silver Certification and savings of 256 tons of CO2 per year of CO2
A building in reinforced concrete and glass with a strong personality from the architectonic stand point, composed of two parts joined together in the two underground levels, with one occupying ¼, and the other, ¾ of the total volume.
The surface of the two underground floors is about 8,700 sq. m while the floors above ground open out to a total of about 13,000 sq. m.
- Compliance with environment constraints, and exploitation of local resources like groundwater
- Abatement of CO2 emissions
- Flexible use of the systems, with the possibility to heat and air-condition different parts of the building simultaneously
Engr. Franco Casalboni, one of the founding partners of the engineering company, Polistudio, and head of the mechanical systems sector of the Feltrinelli Foundation takes the floor.
What elements characterize the project?
In 2008, we had to consider the national and regional regulations on energy consumption restraint. It is clear that in a building where the glass "was the protagonist" and the rest was made of reinforced concrete, the energy performance was a big challenge. All these obligations, together with the fact that in the subsoil of Milan there is plenty of water, led us to choose the ground water heat pumps, which could guarantee very high and constant performance all the year round, because the ground water temperature has annual excursion of only 1 ° or 2 °C.
How did you design the system?
This building is developed along the east/west axis, has very large surfaces extended north and south and, during the same day, there can be the need to heat an area and in the same time to cool another area. The plant was designed as a 4 pipes heat pump plant. The heat pumps can produce hot water for heating and cold water for air conditioning at the same time. The fluid production plant was realized with multi-function water-cooled heat pumps. To manage the summer loads picks, we included a water cooled liquid chiller with multi scroll technology and a heat pump for the domestic hot water production, cooled by the water loop of the air handling units.
One of the constraints imposed by the designers was to have the reinforced concrete at sight, so there were not false ceilings. For this reason we inserted the terminal units in the floating floor and we selected fan coils suitable to be installed below large glass surfaces.
In accordance with the manufacturers, we developed a mockup of the selected devices at the manufacturer’s plant in Germany, where we rebuilt in scale 1: 1 the part of building with inclined facades in order to verify that the air produced by the fan coils was compatible with the comfort of the occupants.
Why did you choose Clivet heat pumps?
The choice of ground water heat pumps fell immediately on Clivet. Over the time we have been able to verify the quality of the machines manufactured by Clivet that offer a performance absolutely on line with the declared values. Clivet also offer a reliable service center that provides prompt intervention also once finished the opera.
What measures have you adopted to ensure the highest comfort level?
Due to the very large glass surface, equal to 10,598 square meters, one of the most important problems we faced was the solar radiation: on the South face we installed external blinds that shield and protect glass surfaces from solar radiation. In this way we obtained the maximum level of comfort with a considerable reduction of cooling loads and energy use. Due to the size and complexity of this realization, we installed also a management system that control all the systems of the building.
The building has an energy class B and has also achieved the LEED Silver certification.