Hotel Laguna
Stylish maritime-inspired building, 5 minutes by boat from Venice

The exclusive NH Laguna Palace in Mestre is known for its stylish maritime-inspired buildings, minimal internal design, and its private wet-dock that is covered by a glass sail, which allows its guests to reach the historical centre of Venice in only a few minutes by motorboat. The original architecture divides the complex into three main buildings. Two house the luxurious 384-room hotel with its exclusive decor. The third building, called the Laguna Conference Center, houses an innovative modular congress centre and the 600 m² open-space Laguna Gallery.

The challenge

The numerous services offered each presented different loading and usage profiles, and different air conditioning needs.
The rooms in the hotel have a fairly stable average occupancy rate compared to the Suites and Conference Center rooms, which are used on and off. Certainly, the common needs were to maintain the comfort required by the prestige of the building, the integration of the systems in the innovative architecture, as well as limiting internal and outdoor noise emissions.

Another non-negotiable objective the customer had was cost optimization in installing and managing such an ambitious and highly visible structure.
During the first technical surveys, the presence of an underground fresh water spring was found. In the past it had been used for the neighbouring industrial utilities, but at that time it was no longer in use.

The building

  • 3 structures: hotel, residence, and conference centre
  • Total Volume 80,000 m3
  • 384 rooms and 1,000 seat conference centre

The team

  • Architectural project: DHK Architects, South Africa
  • Structural project: Favero & Milan Ingegneria, Italy
  • Mechanical plant project: Studio T.I., Italy
NH Hotel laguna palace
The solution

The designers at Studio T.I. developed specialized systems for each of the areas, each characterized by specific needs.

The moderate variability of the hotel's load is serviced by a mixed system. It is a two-pipe centralized hydronic system with primary air and room fan coils. For the variable occupation of the Suites and Conference Center, the system is decentralized with autonomous loop type water-water and water-to-air heat pumps.

The hydronic system of the hotel for cooling is entrusted to chillers with screw compressors and continuous capacity regulation. The air is distributed in the rooms using hidden fan coils with integrated delivery diffuser and recovery. The silent operation required by the customer was attained thanks to the implementation of innovative tangential fans with electronic control.

The loop system serving the Suites and Conference Center uses the nearby underground source, and employs plate heat exchangers that can be inspected, located in the utility room.

This loop feeds a number of autonomous heat pumps that are installed in the rooms served, based on their specific use.

Each suite has a water-to-water unit concealed in a utility room in the hall that feeds the two-pipe hydronic terminal units in the various rooms served.

High-efficiency rooftop water-to-air heat pumps cool the largest areas, such as the restaurants and the rooms in the Conference Center. These are automatically regulated units designed to condition the air in high attendance areas, able to manage the significant air changeover required for hygiene and by law. They are also capable of recovering the energy from the exhaust air using an innovative active circuit with a heat pump.

NH Hotel laguna palace
The system

 

  • Three super-silenced Clivet air cooled screw chillers serve the Hotel with a total of 1.3 MW.
  • More than 100 Clivet WSHN water-to-water heat pumps and one 350 kW air-water heat pump serve the Suites.
  • More than five hundred high-efficiency Clivet ELFO hydronic terminals.
  • Eight rooftop water-to-air heat pumps Clivet CSNX-H with integrated energy recovery for high attendance areas, serving the Congress Center and restaurants.
  • About 3.2 MW overall cooling capacity.

The results

By specializing the systems, the cost of installation and use were limited. The units are easier to manage and provide maximum comfort.

The special source used for the loop left the appearance of the system unchanged and significantly reduced the environmental impact. Furthermore, the water used as an energy source is returned to the wet-dock using picturesque fountains that oxygenate the water and make it useful for the basin.

Heat pumps in the areas with irregular use allow the units to be turned on only when effectively needed, overcoming the traditional waiting periods and costs necessary to bring a traditional system into steady state.