Energy savings of 30 percent was realized after installation of five compact pumps, control/monitoring units and motors.
by Bryan Orchard
January 28, 2019

For art galleries and museums, a priority must be creating and maintaining the perfect environmental conditions to ensure the fabric of their artwork is not compromised. For many buildings of historical and architectural significance in Venice, respecting such a status while managing the humidity, air quality and temperature is both expensive and a major challenge. Venetians have modernized building services infrastructure while honoring the past.

The Palazzo GrassiImage 1. The Palazzo Grassi is characterized by two great façades, one facing the Grand Canal and the other facing Campo San Samuele. (Images courtesy of KSB AG)

The Palazzo Grassi (Image 1) is one of the most famous Venetian buildings, described as “the last patrician building facing the Grand Canal to be constructed before the fall of the Most Serene Republic of Venice.” Designed by Giorgio Massari, it was constructed between 1748 and 1772 and is characterized by two great façades, one facing the Grand Canal and the other facing Campo San Samuele and noted for its majesty and whiteness.

Today, it is the premier contemporary art museum in Venice, having been renovated and rehabilitated for its current purpose in 2006 by the Japanese architect Tadao Ando. Owned by François Pinault, it is now host to his collection of contemporary art, which is reputed to be one of the five largest in the world.

Culture Meets Sustainability

In 2016, following a careful analysis of the past energy consumption, an extensive renovation project was implemented. This involved the renewal of parts of environmental services infrastructure to optimize energy consumption, while at the same time delivering the sensitive conditions required for housing valuable works of art. The essential components needed to achieve energy savings were replacement of hot and cold water pumps, valves, strainers and compensators, all of which were sourced from the supplier by the project contractors Siram SPA. The main goal of the project was to update the hot and cold water systems for the two heating and cooling circuits in the building.

The three pumps for cold water dutiesImage 2. The three pumps for cold water duties are equipped with the advanced control/monitoring unit

“The effectiveness of the heating and cooling infrastructure that maintains the heating and air conditioning throughout the Palazzo Grassi is largely dependent on the water pumps,” said Matteo Zanus, Siram project manager. “Energy efficiency is very important in Italy and no more so in large, historical buildings such as the Palazzo Grassi. Having provided pump maintenance to the Palazzo Grassi over a number of years, Siram was contracted to undertake a refurbishment of the pumps facilities, a task involving the installation of three cold water pumps and two hot water pumps.”

The water used in the system is refreshed by pumping water from the lagoon using two submersible pumps.

The salinity and pollution of the water, as well as temperatures changes, are elements that must be dealt with before the water can be used in the closed-loop systems.

Filters remove the pollution, a small desalination plant removes the saline content and two heat exchangers adjust the water temperature to meet the building’s operating requirements.

Making Pumps Pay

Modern centrifugal pumps have already achieved a high level of efficiency. When the pumps appear to be consuming more energy than necessary, it is probably due to lack of attention. Any pump can only operate as efficiently as its system—including valves, piping, filters or heat exchangers—allows it to. At the Palazzo Grassi, the performance of these components working as one ultimately affects the controlled environment within the building.

Designing and installing a completely new pumping infrastructure for air conditioning and ventilation in a historic building does present a challenge, especially because the buildings were never designed for such equipment. In the case of the Palazzo Grassi, the pump room on the lower ground floor is best described as “compact.” Therefore, the first consideration was finding five suitably sized pumps, two for hot water circuits and three for the cold water circuits that could deliver the water flows and pressures for the system. Then there was the matter of connecting new piping to the existing infrastructure. Finally, there was meeting the user’s requirement for energy efficiency.

Fortunately, these three requirements could be satisfied by using compact, close-coupled pumps that are equipped with an advanced control/monitoring unit. Three of the pumps are driven by an energy-efficient motor that meets class IE5 requirements, and two are driven by IE4-class motors. All five pumps are fitted with a modular, self-cooling frequency inverter.

Compact, Close-Coupled Pumps

These pumps have proved successful in many applications around the world over several decades and are especially useful where space is at a premium because the pump, the advanced control/monitoring unit and motor are connected in one compact unit, giving it a space-saving design.