After the hotel had operated successfully for 14 years, it was time to evaluate and improve how the HVAC plants at the Radisson Blu Palace Hotel are run and operated. Persy Control Services, a long-time certified Siemens partner, took on this task and helped the hotel establish a basis for reducing its energy usage by as much as 25% – decreasing operating costs significantly while strengthening the hotel’s ambitions in terms of sustainability and energy efficiency.
The Radisson Blu Palace Hotel achieved the Green Key award in 2011 and has been improving its own green footprint ever since. As part of its efforts, the hotel even provides a special parking area for recharging electric cars – at no additional costs.
The hotel also takes part in the Think Planet initiative to reduce energy consumption by 25% within 5 years. To maintain the Green Key status as well as to reach the ambitious goals of the Think Planet initiative, the Radisson Blu Palace Hotel needs a modern, reliable building automation system that controls the numerous heating, ventilation and air conditioning (HVAC) plants and the main heating and cooling plants in an energy-efficient way.
Long-term partnership of cooperation and trust
The 6-story building was constructed in 2001 and has 120 guest rooms, two restaurants and a lounge, 13 conference rooms and a wellness area, including an aquatic center. Because of their usage, each area requires a different climate, depending on the time of day, the outside temperature and other factors. Consequently, after 14 years in operation, it was time to take a closer look at the installed HVAC plants and the way they were being controlled and operated. Originally, the hotel’s building automation system had been planned, installed and commissioned by Persy Control Services, a certified Siemens Solution Partner for building technologies.
For this reason, hotel management once again turned to its long-term partner in 2014 to review the existing building automation infrastructure. As a Solution Partner, Persy Control Services was able to evaluate the current status of the plant operations in the hotel with the support and technologies provided by Siemens. This includes not only product support. More importantly, Persy Control Services has access to multiple calculation tools which help analyze the building automation functionality of the HVAC plants as well as the new “best case” efficiency status after modernization. The Energy Performance Classification (EPC) tool, for example, allows for an initial assessment of the current control strategies and an estimation of potential energy savings and payback time thanks to improved building automation functionality. This assessment is fully based on the standard EN 15232:2012 “Energy performance of buildings – Impact of Building Automation, Controls and Building Management.” If required, additional tools and means are available to analyze the savings potentials of selected plants and building areas in more detail. This helps uncover the largest savings potentials and set implementation priorities.
Following the outcome of these estimations and calculations, both hotel management and its Solution Partner could decide which steps to take first and how to prioritize the modernization measures. What’s more, the tools could also be used to show possible energy savings and thus energy cost reductions. This made it possible to directly correlate the modernization costs with potential savings, emphasizing the benefits of a modern building automation system.
Moreover, this would also give a preview of how far the hotel has come in reaching its goals for the Think Planet initiative.
Starting the project – modernize multiple ventilation plants
At the beginning, the current state of the hotel’s HVAC plants had to be evaluated by sight. An initial walk-through of all plants produced an overview of settings, products and dependencies between the plants. In this case, it was expected that the main air handling units were the key causes of high energy consumption. Due to the variety of areas in the hotel, multiple ventilation plants are installed to serve the different parts of the hotel. Although this is a common way to organize ventilation in a hotel, in this particular case it was found that not all timer programs, setpoints and control strategies of the plants were aligned with the actual usage of the rooms and facilities.
Using the findings from the initial walk-through, the EPC tool was used to obtain more detailed insight into the improvement potential of the plants. All recorded settings of the HVAC plants, timer programs and other relevant factors were considered to provide a first analysis of the current state.
Energy savings of up to 25%
The estimated potential energy savings for the hotel based on a relatively small investment was remarkable. The results not only impressed the owners of the hotel but also increased awareness for potential reductions in CO2 emissions. Energy costs could be reduced by as much as 25% solely with improvements to the building automation functions. The high energy-savings potential also results in a shorter payback time for the investor – and a better sustainability and energy efficiency record. After all, plant modernization will bring the hotel one step closer to reaching its energy efficiency goals.
Based on a more detailed analysis of certain plants, it was then decided in which areas to start and how to prioritize the required modernization steps. As already seen during the initial walk-through, the most urgent step was to improve the controls of the main ventilation plants. It was crucial that the project would not impair the comfort of the hotel guests at any time. For this reason, the plants were upgraded one after the other.
The building automation system of the Radisson Blu Palace Hotel was migrated from the existing Unigyr system to modern Desigo controllers and a BACnet communication-based system which offers state-of-the-art building automation functionality. Variable speed drives, sensors and actuators were installed or replaced where necessary. Going forward, ventilation will be demand-based, i.e. only as much air as needed is provided to the individual rooms while maintaining the required comfort and indoor air quality conditions. In addition, the existing individual room controllers in the hotel rooms were easily integrated into the new Desigo system. This allows for improved supply control of hot/cold water to the rooms for heating or cooling purposes. These improved control functions save a remarkable amount of energy, thus lowering energy costs and improving the green footprint of the hotel.
Ready for the future
During the planning phase, both the hotel and Persy Control Services kept the future in mind. Thanks to backwards compatibility and open communication standards such as BACnet and KNX, upcoming changes, modernizations (e.g. hotel room renovations) or adaptations can easily be integrated into the new Desigo system.
The upgrades within the ventilation system are a key step toward more efficient building automation management in the hotel. The benefits not only include cost savings and a short payback period. More importantly, the hotel has managed to get closer to its goal of achieving a green footprint in its community.
The first modernization measures were completed in 2014. Other system improvement opportunities will be evaluated in the future to get the most out of the building automation system.