April 2011
Energy has become a hot topic with vendors and standards organizations, many of which are offering and creating solutions for energy users. Most governments around the world view energy as a key economic and national security issue and are promoting conservation and SmartGrid concepts to save energy.
In the last two years, I have attended many presentations by organizations, standards groups, and vendors about energy and the SmartGrid. They majority of these presentations are made up of a long list of statistics about energy history (consumption trends, costs, dwindling resources, etc.) and future impacts if we continue to do nothing. The presentations then discuss long established fundamentals of energy conservation and optimization at a macro level. I am surprised how these energy fundamentals are presented as a surprising revelation, because energy conservation has been an issue for years, if not decades.
Because of this fact, I do not have confidence that the presenting organizations and companies are experts yet.
Energy conservation and optimization is simple but not easy. Like playing golf, make par for 18 holes and you have a good game – easier said than done! The simple part is defining the basic steps: understand where energy is being consumed, eliminate waste, optimize utilization, and replace poorly performing equipment. Each step takes more knowledge and investment to accomplish. It is not a linear process.
Similar to the standardization of control system networks that ultimately created a wide range of different standards, these energy related activities have the potential to spawn a number of transaction and data definitions embedded in protocols that are all somewhat different. So there we go again!
Partitioning of functions is tricky and I think care needs to be taken when winding the concepts of energy optimization too tightly with automaton protocols. This may create some strange outcomes and “boat anchors” for users that adopt them.
Any control engineer that has experience interfacing controllers, RTUs, and instruments in a system where each of device represents floating point numbers differently can appreciate the need for standardized data. Fortunately, most devices now conform to the IEEE Standard for Floating-Point Arithmetic (IEEE 754). We need this kind of standardization for energy data from end device to utilities.
The common problem for all the groups is defining common data models for energy and energy control information. Without collaboration, each group will develop a unique model that will be need to be translated at different levels of system architecture - from energy consuming devices to utilities via the SmartGrid.
Based on my experience designing optimization and power demand systems, I know that the majority of energy optimization is supervisory control with response requirements in milliseconds or much longer. The exception is highly sophisticated process optimization that is hard core real-time control - precisely what our present industrial networks are designed to support.
The building automation industry has been miles ahead of industrial automation in the monitoring, optimization and load control of energy. I have personally done this for years-in a previous job-before it was an issue in industrial automation. Although still in its application infancy, the building automation industry and energy providers are using web services to manage optimize, bid, and reverse auction bid for energy today. The building automation industry has been refining protocols and implementing WEB services to improve energy optimization. I was involved in major building automation industry discussions and debates about the roles of protocols and web services that started in 2003.
In my opinion, building automation experts, with their longer history of understanding energy and energy optimization issues, have consciously sorted out functions for protocol and web services. Is it perfect? No, but it is more refined than what is happening in industrial automation.
Web services leverage the IP infrastructure that is becoming the information highway for voice, video, and data. Web services enable network transactions to be more intelligent and are based on broadly accepted standards. A big argument against its use has been that network bandwidth is too low but this issue is rapidly going away in plants. As IPv6 is deployed, IP based communications for everything makes even more sense. It is highly likely that the majority of companies will work towards a single IP network infrastructure.
Having Multiple IP network technologies within a plant adds capital expense to the network, increases maintenance costs, lowers end-to-end performance (more gateways, routers, etc.) and negatively impacts security. This is an architectural change that appears to be happening throughout an enterprise.
OPC UA is a good candidate to provide the web services based standard for energy for industrial applications.
Existing installations need to look at their energy situations and take actions now. Fortunately, it is relatively easy to start an energy savings program now regardless of installed network or systems.
The good news is there are a lot of organizations focusing on automation for saving energy. The other news is there are many groups with initiatives so I have included introductions and links to many if you would like to learn more.
I am certainly interested in your thoughts and insights on this topic. Use the "Feedback" link at the bottom of this article to contact me.
These are groups that are working on standards related to energy monitoring, optimization and SmartGrid:
