Anyone designing an IoT architecture must decide which tasks are best performed locally by a device at the network’s edge versus remotely by a cloud-hosted application. Within the IT world, an edge device is defined as a gateway or global controller. Within the building automation world, a direct digital controller (DDC) can be considered an edge controller. Likewise, a global controller is an edge controller. Physically, the network’s edge might be integrated into roof-top equipment, solar arrays, utility-owned equipment, data center infrastructure, etc. The EAC marks a new generation of edge-device in that they will come with tagged, preconfigured apps to automate the workloads typical at these edge locations.
One of the most revolutionary aspects of having robust compute resources at the DDC level is that edge devices like energy analytics controllers can do analytics processing of large data sets. Application developers are challenged to make the most of this new capability. The Buildings-IoT represents an opportunity to radically rethink the software architectures that define core workflows such as detecting and diagnosing faults in equipment, responding to occupant hot/cold calls, shifting energy loads to participate in demand response programs, and performing other building operations management tasks. Energy analytics controllers are capable of high-speed handling of the work involved in trending data, adding semantic tagging and generating analytics. Doing these tasks locally and sharing the results among other edge devices opens the path to a host of new applications.
The basic resources that an energy analytics controller should integrate include a powerful processor, on-board memory, flash storage and IP connectivity. The open Sedona Framework is the type of real-time controls engine that works well in a software architecture built to support EAC devices at the edge. Essentially, app assembly happens here. Using easy-to-learn graphical block programming methods, solution developers can define desired inputs and outputs to EACs. Tridium has opened the Sedona Framework to the public with an academic free license and it has self-sustaining community support.
Another trend is to run building services on an IP backbone, bringing high-speed Ethernet connectivity all the way to EAC devices. This provides unprecedented capacity to store and compute data on the edge. A Smart Building System Integrator can use this broadband capacity and the EAC’s resources to fundamentally change how equipment is controlled. At this point, it becomes practical to design solutions that involve: