Sep 1, 2015 - Building
“If No One Feels Chilly, Then Energy is Wasted”
- When you increasingly incorporate self-optimizing systems into building technology, do you then eliminate the natural behavior of your colleagues to pull on a sweater, when it gets cold?
Zerbst: Our building technology is designed to offer a maximum of economically feasible user comfort. Efficient operation does not mean freezing in winter and sweating in summer. It cannot, however, be the goal to no longer need to adapt to the seasons. We therefore follow an approach by finding the limit at which the first person states that it is too hot or cold for him or her. When I find this point, and then adjust to right above it, then all are satisfied. If no one is too hot or cold, then I am wasting energy.
- That sounds like a nice side effect, because this requires a certain level of communication within the company, doesn't it?
Zerbst: Yes, indeed. When you introduce a continuous improvement process with the goal of sustainably increasing energy efficiency, to do a little bit better every day, then you have to discuss this with your colleagues and bring them on board. We have, up to now, achieved quite a bit in communications, which then leads, for example, to colleagues openly reporting problems. We are then, in turn, in a position to quickly repair defective system equipment or to optimize settings. Comfort is foregrounded. This is because energy efficiency does not function long-term when comfort is ignored; therefore, an energy management system becomes a reflection of corporate culture.
- Are you ever done with the work?
Zerbst: That is not the assumption. Nothing functions perfectly by itself. Therefore, we don't stop when we have discovered possibilities. And the ISO 50001 also provides explicitly for dynamic action. If we did not constantly deal with the increasing complexity of system and building technology, we would quickly fall back into an energy-inefficient range. For example, if the circumstances or use changes in a building area, we have to react. We also have a lot of diverse viewpoints in our work, and we combine these with the building technology.
- What does that mean specifically?
Zerbst: From a maintenance point of view, problem-free operation is foregrounded. An Energy Manager's goal is the greatest possible energy savings during operation. The Facility Manager, on the other hand, prefers the highest level of user-friendliness. These three perspectives quickly clarify the point that installing building automation or a new control system does not save money. Therefore, we have to make the correct decisions regarding the entire system.
- How important is the topic of retrofitting with regard to investments in energy efficiency? After all, it is constantly under construction.
Zerbst: It is very important, because many measures directly address modernization or even — as at our facilities — an expansion of the existing infrastructure. Thus, a new control technology doesn't automatically save money — it has to be correctly set. For this purpose, we collect experience from system operations and transfer it to other systems or facilities. The results are additionally incorporated into new projects and renovations. As a whole, it summarizes quite well how sustainably we act.
- Does this method limit you to single systems?
Zerbst: Let's use a Combined Heat and Power Plant (CHP) as an example. The system does not exist alone in a new construction; instead, it is located directly adjacent to the existing heating system, which was in turn installed at WAGO in 2008, including a control cabinet and controller. The CHP likewise had its own controller in its own cabinet. Ever since then it was clear that retrofitting always has to includes integration as well — and this means spatially as well as regarding technical data.
- How did you solve this technically?
Zerbst: We could keep the existing furnace controller, that is the structure and control hardware, the way it was. We installed the control cabinet for the CHP directly next to it and connected the two. Our WAGO-I/O-SYSTEM 750 offers very good possibilities for this. We linked the existing heating system, using the LON® communication selected for it at the time, via a LON® I/O module, to the ETHERNET, which made the furnace into a participant in the total system. This was super easy: we did not have to convert the drives, sensors, or actuators. This ultimately makes retrofitting more economical, because the integration of modern technology does not always result in mandatory replacement of functional equipment simply due to its age.
- Does this type of uncomplicated integration alleviate the fear of investing in modern building technology?
Zerbst: I am convinced of this. On the one hand, the size of the investment drops to a much lower level. On the other, I can implement modernizations gradually over time, without causing problems that will arise later because the older technology can't speak to the newer, and vice versa.
- Thank you for the conversation.