At the heart of the Bergisches Land district of Germany is the idyllic Große Ledder seminar and recreational hotel complex set in a wooded area of 50 hectares. In eleven individually designed buildings, which are spread throughout the hilly landscape, there are 91 comfortable bedrooms and 13 light and airy conference rooms with modern media systems. The hotel is run by Bayer Gastronomie. In 2008 the process of gradually modernising and, where necessary, converting the buildings began. Intelligent building technology and a KNX network allow the separate facilities to be managed from a central location. They also make a significant contribution to saving energy and ensure the highest level of comfort for the hotel guests, while creating a strong sense of brand recognition.
The first houses on the site were built in the mid 18th century and were very soon turned into a convalescent home for Bayer employees. Now the hotel is open to everyone. The buildings are distributed across the extensive wooded area and seminar participants have the opportunity to stroll in the woods between sessions. In 2008, Bayer Real Estate began by converting the central reception building. A modern structure was added during this phase of the construction project to link the farmhouse and the manor house together.
brandherm + krumrey interior architecture was responsible for the interior design of the farmhouse and the Böttinger house. The client specified a 3-star-plus level of accommodation with a design and materials that give a timeless yet modern and durable feel. It was important that the furniture was of high quality and made to last. "The conversion of the Böttinger house in 2010 was particularly interesting, because it is a listed building as a result of its striking facade. We wanted to create a modern hotel ambience, while retaining the building's historic charm," explains interior designer Sabine Krumrey. The house was completely gutted inside, leaving only the facade and the hall area intact. The bedrooms and bathrooms were rebuilt and newly furnished. The building now has 27 single rooms with queen-size beds. The rooms have a bright and friendly design that conveys a sense of timeless elegance. The colour scheme consists of white and warm earth shades. The windows are reproductions of the originals and the building has been rewired and replumbed.
The central manor house, which dates back to 1777, was completely renovated in 2012. With its facade covered partially in dark grey slate and its green shutters, the house is typical of the architectural style of the Bergisches Land. It has five suites and three double rooms offering the highest quality accommodation. Here too, shades of brown and white predominate, creating an elegant ambience. A clear division has been made in the suites between the working, living and sleeping areas. A wine merchant's store has been established in the old vaulted cellar of the manor house where guests can taste wines in a comfortable setting.
The buildings of the Große Ledder have retained their historic exteriors, but their interiors are more modern than many other hotels. Because the buildings are spread over a large area, linking them together with a modern building technology system makes running the hotel considerably easier. This means that the rooms that have already been modernised and equipped with the appropriate systems can be checked from a central location to see whether the minibar is working, the air conditioning is in operation, the windows are open, although the guest has already checked out, or whether there are any faults, for example with the heating system. It is even possible to tell at a glance whether the rooms have already been cleaned. The new system has also had an impact on the buildings' energy consumption and the electricity costs have been significantly reduced.
The management team of the Große Ledder received expert advice on intelligent building automation from the electrical engineer Thomas Hering. He explained the options available with a modern KNX network and identified the most appropriate solutions. The aim was to install a system covering the entire hotel which was easy for both staff and guests to use. The hotel management needed a system that provided technical transparency at all times. This includes having an overview of the status of the rooms, the energy consumption and all the fault reports. An intelligent energy management system that operates unnoticed by the guests was another key requirement.
Elektro Hering commissioned the system integrator Willian Vent from microswitch to program the system and produce detailed plans. Together they created a KNX system to link the individual components and functions, including the heating, air conditioning, ventilation, lighting, media and audio systems and locks. The hotel's reservation system is also integrated via a special interface which allows rooms to be prepared automatically after the reservation has been made and the guest has checked in. All the data is stored on two redundant Gira FacilityServers which lie at the heart of the system. The joint project run by Thomas Hering and Willian Vent has already won the Gira System Integrator Award 2014 and the Energy Efficiency Prize 2014 awarded by the ZVEH (German association of the electrical and information technology industry).
In the manor house, the KNX system offers almost all the available building technology functions that are needed to ensure the cost-effective operation of the building and the comfort and safety of the guests.
Self-monitoring rooms and suites If a room is reserved via the Protel hotel reservation system or a guest checks in, this information is automatically sent to the KNX system. As a result, the heating is switched on well before the guest's arrival to bring the room up to a comfortable temperature. The service staff do not need to go to the room to check that everything is as it should be. The rooms report automatically whether they have been cleaned or whether there is a technical fault with the lighting, heating, air conditioning or TV. If the room is occupied, it is possible to tell at any time from the central location whether the room can be cleaned or whether the guest does not want to be disturbed. A total of between 80 and 120 group addresses control all the technical processes in the rooms unnoticed by the guests.
Making life easier for the service staff Elektro Hering and microswitch have developed a special display system to help the hotel employees. One glance at a floor plan of the hotel shows the status of all the rooms. They can tell whether staff or guests are present in the room and therefore whether it can be cleaned or not. This status display significantly reduces the workload of the hotel employees, because some of the buildings are a long distance apart. The remote maintenance option also saves time and makes the job of the staff easier. If a guest has a technical problem, it can often be resolved remotely. A member of the hotel team can adjust the temperature in the room, the lighting or the air conditioning system. if required. The system also displays a variety of fault reports, allows the external lighting to be switched on and off and monitors the barriers at the entrances using cameras.
Comfort for guests The doors of the rooms open when an entry card is held in front of the lock. The Messerschmitt lock system is integrated into the KNX network. Different functions and permissions are assigned to service staff and guests. When a guest enters a room, he or she is presented with an individual lighting scenario. If guests have already stayed in the hotel and have saved a scenario with lighting and TV or radio programmes as their favourites, they will see these on arrival.
Hands-free calls One very useful feature is the hands-free unit in the rooms, which allows telephone calls to one or more people to be made from anywhere in the room. The guest's smartphone is simply connected to the room system via Bluetooth. It is equally easy for guests to play their favourite music on their smartphones. Concealed loudspeakers in the bedrooms and bathrooms provide excellent sound quality for music, radio and television.
Intuitive control functions for guests Almost all the lights can be dimmed using DALI and 95% of them are fitted with energy-saving LEDs. The lighting and the room temperature can be controlled using classic Gira Esprit Glass C Black switches with an elegant design or the intuitive Gira interface on an iPad which is given to guests for the duration of their stay in the manor house. On the iPad guests can also save individual lighting scenarios and wake-up scenarios with TV programmes and lighting. These are stored permanently on the system and guests can access them during subsequent visits, even if they are staying in a different room.
Automatic fault reports improve safety The system generates fault reports in all safety-related areas including the air conditioning, heating, ventilation, pump systems, lifts and emergency lighting. The light fittings also report faults and the weather station sends alarms in the event of high winds. All the information is transferred to the Gira FacilityServer and displayed in a central location. Depending on their priority, the reports are then sent on to the employee responsible by phone or by e-mail. If the two redundant Gira FacilityServers crash, all the important functions, such as fault reports, fire alarms and emergency lighting, remain in operation.
If the Bosch fire alarm system is triggered, the alarm is sent to the relevant service staff via KNX with the highest priority. "In future, specific alarm information will be given to guests in their rooms in the form of audio messages, for example 'Please leave the building via the left-hand stairwell', in German or English, depending on the guest's booking status," explains Thomas Hering. This useful function is still under development.
Intelligent use of energy The intelligent integration of the heating into the KNX system allows the temperature to be controlled according to the reservation status of the room. KNX room temperature controllers report the current readings and, on this basis, the heating brings the room to the specified temperature. The temperature is reduced in unoccupied rooms and then increased again before the next guest checks in. Window contacts are used to monitor whether the windows are open or closed. If a window is open, the temperature is automatically reduced to ensure that no energy is wasted. Depending on the room's reservation status and the time of year, the air conditioning system may also be involved in this process. Guests can adjust the electric underfloor heating and mirror heating in the bathroom themselves by +/- 3°C to suit their requirements. The LED lighting in bedrooms, suites and conference rooms and the LEDs used in some external lights and the emergency lighting system significantly reduce energy consumption. These long-life lights also help to lower CO2 emissions and the amount of maintenance needed.
Incorporating existing systems Elektro Hering and microswitch have equipped existing systems in other buildings at the Große Ledder, such as air conditioning, ventilation and heating systems supplied by a range of manufacturers, with KNX interfaces, which allows them to be integrated into the KNX world and made "artificially intelligent". This means that these systems can also be operated via the central display unit and any fault reports that they produce can be recorded and passed on.
Seminar rooms The blinds in the seminar rooms are adjusted automatically on the basis of the data from the central weather station and the accompanying safety systems, such as the wind and frost alarms. They can also be operated manually using the Gira push button sensors on the wall or the iPad in the room. The display on the iPad also allows the lighting and the conference media to be controlled. The energy-efficient lighting system adjusts to the amount of daylight available. If it gets lighter in the room during the course of the day, the lighting is gradually dimmed. As it grows darker outside, the lights become brighter.
The result of the close cooperation between the hotel management, the electrical engineer and the system integrator is an intelligent, "thinking" hotel that is equipped for the future. On the basis of the KNX infrastructure, functions can be reprogrammed, enhanced or added at any time, without the need to make alterations to the building or drill holes in the walls.
