## 3 Methodology: Requirements Analysis, Selection of Buildings, and Technologies
### Deriving Technologies and Instrumentation Variants
#### 3.3.3 Selected Variants
In case of undesirable behavior, the \"kill switch\" will disable cloud-access to the underlying BACS and activate local, KNX-inherent controllers for, e.g., heating the building. Figure 4: Equipment concept for one floor and wing of an exemplary building layout using EnOcean and KNX. The cables for backbones are orange for EnOcean and green for KNX. The KNX backbones are only indicated for the room in the upper left side, to keep the figure readable. \begin{table}
\begin{tabular}{l l l l} \hline \hline
**Device Type 1** & **Manufacturer** & **Model Name** & **Purpose** \\ \hline Presence Sensor & MDT & SCN-P360K4.03 & \(\bullet\) detect occupancy (PIR) \\ Presence Sensor & Steinel & True Presence & \(\bullet\) detect occupancy (high-frequency technology) \\ Presence Sensor & Steinel & True Presence & \(\bullet\) detect occupancy and measure illumination, air quality \\  & & Multisensor & \\ \hline Person Counter 2 & Steinel & HPD2 & \(\bullet\) count the number of persons in a room \\ \hline HMI & MDT & BE-GT2 TW.01 & \(\bullet\) enable input of user set-points \\  & & & \(\bullet\) display current room state (e.g., air quality, blinds position) \\  & & & \(\bullet\) give feedback to users (e.g., suggest to open a window) \\ \hline Blinds Actuator & MDT & JAL-B1 UP.02 & \(\bullet\) control blinds slope and position (local) \\ Blinds Actuator & MDT & JAL-0210.02 & \(\bullet\) control blinds slope and position (central) \\ \hline EnOcean/KNX Gateway & Weinzierl & KNX ENO 634 & \(\bullet\) convert bi-directionally between EnOcean and KNX \\ EnOcean/KNX Gateway & ABB & EG/A32.2.1 & \(\bullet\) convert bi-directionally between EnOcean and KNX \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Overview of KNX devices installed in addition to the EnOcean devices. Integration of BACnet  
To include automation elements which are connected via BACnet protocol, a connection is also planned and is currently in a first testing phase. BACnet is used especially for automation elements that are relevant for the building instead of the room level, e.g., the control of a heater system feed temperature. To maintain safe operation, again, the \"kill-switch\" principle will be used. Therefore, additional switching elements are going to be introduced in the BACnet automation and a limited access for scientific purposes will be available via an OPC UA [73] server. Another key aspect within LLEC, which is enabled by the use of the BACnet protocol, is the demonstration of the LTDH network, which integrates waste heat from _high-performance computing_ (HPC) resources into the heat supply of surrounding buildings [74,75]. The buildings that will be connected to the LTDH are shown in Figure 5. A section of the existing district heating network is repurposed and extended with new pipes where needed to accommodate the increased mass flows, in order to form the future LTDH network. At the different building connections, orifice plate measuring sections are planned for an accurate measurement of the flows. Since the waste heat's temperature is too low to supply the heat demand of the existing buildings without retrofitting them directly, heat pumps are installed. Via the heat pumps, a connection is established between heat and electricity, which, e.g., allows for the use of the thermal capacity of buildings as a storage, which, in turn, allows for the operation of the heat pump in such a way that the electricity grid is supported. To have a detailed insight on the effects and to have the potential to act on multiple levels, the buildings connected will be equipped with sensors and actuators at the room level, along with additional meters as well as full access to the heat pump with the associated heat storages. This setup makes it possible, for example, to examine the flexibility potential of different buildings for the electricity grid in detail. Integration of M-Bus Metering  
For metering several consumption data points, access to measurements is two-fold in the solution we derived and plan to derive for use in FZ Julich.