By Raymond E. Cline Jr., College of Technology
To witness evidence of the cyber physical revolution, all I need to do is walk the dogs. As I walk through my neighborhood, I see reclosers (“switches”), smart meters, take-out points (communication hubs for that meter data), and a fully instrumented substation. These are all elements that make the smart grid intelligent. I see cars that have keyless entry, keyless ignition, back-up cameras, automated self-parking, hybrid power plants, fully battery operated vehicles, and soon- fully autonomous driving. Coupled with the traffic cameras, pavement sensors, and traffic flow analysis, we could see fully optimized traffic patterns in the future.
As I walk, I reflect on the progress made in digital oil fields, made possible by a plethora of embedded sensors, complex analytics, and automated operations. The combination of sensing, modeling, controlling, and optimizing physical systems has been around for a long time, but even the traditional realms of process control and operation are being revolutionized using cyber physical systems approaches.
The latest phrases to describe such systems include Internet of Things, Industrial Internet, Industrial Internet of Things, Fog Computing, and many other emerging terms. Most of these concepts suggest that the goal is to connect All Things to the Internet.
The challenge with that concept is two-fold:
1) These things cannot always be connected to the Internet.
2) Centralizing control, modeling and optimization will produce performance delays that may degrade the reliability of these cyber physical systems.
Particularly in energy systems, the edge is often remote and degradation of decision performance can be catastrophic. So, perhaps the greatest challenge in energy-related cyber physical systems is providing the utility of the interconnection of things at the edge, perhaps a better definition of Internet of Things, with distributed operations, control and optimization, which utilizes the full power of connectedness when available.
Perhaps the clearest example of these two approaches to systems development is shown by the interaction of smart grids and microgrids. A fully “sustainable” design for local power (residential or commercial) would require power generation (usually solar, wind, or a combination), storage, sensors, controllers, and an intelligent operations system. In a stand-alone configuration this is often referred to as a microgrid. If I can connect my microgrid to other microgrids, or to a larger electric grid, then I can improve reliability by sharing power to cover imbalances that might occur by over or under production/utilization.
The All Things Connected architecture would view these microgrids connected to a larger smart grid, which itself has larger generation, storage and control capability. The Living at the Edge architecture would view the system as composed of interconnected microgrids, which could take advantage of a smart grid if it were available. The All Things Connected approach is the system architecture of choice in the United States, Europe, and any location that already has an established electric grid. The vast majority of the emerging economies do not have the benefit, or the burden of an existing infrastructure. They will likely evolve using the Living at the Edge approach.
Living at the Edge is actually the approach many, if not most, energy systems need to utilize. Upstream oil and gas operations are seldom in areas with fully developed infrastructure. Even refining operations are often required to operate “off grid” when power demand reaches critical levels. Pipelines are often the conduits for infrastructure to and through remote areas. So, Living at the Edge of the cyber physical world is a common necessity for energy systems.
As we consider developing cyber physical systems which support Living at the Edge, we still want to leverage the qualities of the “internet.” This may have many meanings, but at least it implies the use of flexible protocols, establishment of services which support the rapid development and deployment of solutions, and a flexible set of “standards” that promote, in the words of my friend Ben Horowitz, “rough consensus and working code.” We must also incorporate the concept of “best effort” in a slightly different manner than the application of that term to Internet Protocol (IP). Living at the Edge best effort involves being able to live stand-alone or connected, and knowing/exploiting the differences. So, what are some of the system characteristics that we might need in this model of the Industrial Internet of Things (at the Edge)?
- Internet of interacting things – we should rely on things interacting with things, rather than demanding that all things interact over a single logical network.
- Modularity and self-assembly – our system components must have the flexibility to stand-alone and assemble in larger, more capable forms.
- System Awareness – in addition to providing situational awareness (information about the surroundings and those things the system is sensing) our systems must be aware of their level of self-assembly and the capabilities that this may offer.
- Data and service standards – data is the life blood of the system and services are the mechanisms by which data is produced, consumed, transmitted, stored, and transformed for use by the system. The life blood must flow smoothly and nourish all components if the system is to survive.
- Distributed control – stand-alone and partially connected operation will require models of distributed control, rather than reliance on centralized operation and control.
- User/utility experience – the concept of user experience must go beyond the interaction that humans have with the system to include the environment that other components experience when they interact with each other and the system.
- Behaviors and profiles – encapsulation and isolation will limit how components interact with each other, so the most flexible designs will seek to standardize behaviors and profiles, rather than detailed architectures.
As I walk the dogs and observe the burgeoning world of the energy cyber physical systems around me, these are the characteristics that come to mind. What is certain is that management of the edge is essential for energy systems. Living at the Edge design is perhaps necessary for the future of energy. You may agree or disagree, but this much I know, as long as they have food, water, toys, walks and cuddles, Buffy and Glinda don’t much care. They will leave those details to me.