Energy-efficient buildings: they’re automatic!

It’s a glimpse of the future that seems promising: after a cold winter‘s night, a heat pump generates warmth destined specifically for the kitchen and living room; at an office, only the workstations where people are actually working are lit; and an electric car is being charged in an optimized way that prioritizes photovoltaic energy from the roof. Measures like these bring us closer to the dream of climate-neutral private homes and large buildings. However, making this scenario a reality requires the individual devices involved to be interconnected in a comprehensive way – and lots of energy, of course, usually in the form of electricity. “We’re doubling or tripling our electricity requirements,” explains Dr. Severin Beucker, founder and partner of the Borderstep Institute for Innovation and Sustainability in Berlin. However, Beucker believes that increasing the energy efficiency of buildings is a very good response to this greater demand.

“Efficiency is the order of the day,” he affirms. This formerly niche topic has taken on a new significance in recent years due to the rise in energy prices. Meanwhile, there is the general need to rethink building use and energy consumption in light of climate change. “Overall, too little attention is being paid to the subject of efficiency in the energy transition,” says Beucker. The potential is huge, even with small adjustments in individual households. Every degree lower in room temperature results in energy savings of around six percent. Thanks to building automation, however, a lower temperature does not necessarily mean less comfort at home. Instead, this new technology facilitates the precise control of relevant appliances.

Building sector accounts for 35 percent of all energy consumption

Calculated at a nationwide scale, building automation is a very important factor with regard to climate protection. After all, the building sector accounts for around 35 percent of Germany‘s total energy requirements, and around 40 percent of the world‘s CO2 emissions are attributable to the construction and use of buildings. The industry association Bitkom estimates that an ambitious expansion of building automation could save up to 14.7 million metric tons of CO2 by 2030. “And that‘s if around two to three percent of Germany‘s existing buildings are automated every year,” says Beucker.

Making even better use of building automation components with AI

For this expansion to succeed, the right technologies are needed. As it happens, Germany is at the forefront of manufacturing components for building automation. Such technologies have actually been around for much longer than one might think given the more well known proprietary solutions offered by Google, Amazon or Apple. Particularly in commercial use, the hard-wired, manufacturer-independent KNX fieldbus plays an important role. A fieldbus is a system that connects field devices such as sensors and actuators in a system to communicate with an automation device. More than 500 member companies are now active in the KNX Association, the alliance of manufacturers of corresponding technology.

“All these companies’ products can communicate with each other,” says Michael Schuster, managing director of Enertex Bayern GmbH. In view of the growing calls for greater energy efficiency, it only makes sense to develop more products in this way. Enertex is currently also working with the Friedrich-Alexander University of Erlangen-Nuremberg (FAU) on the research project KoSIR, which involves developing radar sensors that accurately detect the presence of people in a room. Radar technology has a significant advantage over conventional motion detectors, which are activated by any type of movement. “With motion detectors, the light also goes on when a dog or cat walks past,” says Prof. Dr. Björn Eskofier, holder of the Chair of Machine Learning and Data Analytics at FAU Erlangen-Nuremberg. This leads to unnecessary energy consumption that may be of little consequence for a single motion detector, but is significant on a large scale. Radar technology, on the other hand, identifies people and could be used in settings like office complexes. Then areas would only be lit and heated when occupied. “If everyone is gone, you can gradually switch off the heating,” says Eskofier. Although KoSIR is still a research project, future radar technology could be so simple (thanks mainly to artificial intelligence) that it might really be found in buildings. “AI is what enables us to exchange data,” the scientist points out.

Battery-free wireless solutions on the rise

Sensors, buttons, displays and actuators are becoming increasingly efficient. Indeed, the current trend is towards battery-free systems that communicate via radio and therefore no longer even require complicated wiring. So-called “energy harvesters” draw the power they need to operate directly from the environment – either from simple keystrokes or things like small solar cells, the type found in school calculators. One company driving the advancement of such technologies is Oberhaching’s EnOcean GmbH.

The fact that battery-free devices are becoming increasingly important is also due to current developments: “The focus on saving energy has changed significantly,” reveals Matthias Kassner, product manager at EnOcean. The company manufactures wireless devices that are self-sufficient, drawing power from kinetic and solar energy, temperature differences or electromagnetism. Their sensors often require just a few microwatts. However: “You have to differentiate between commercial buildings and smart homes,” Kassner says. In large hotel or conference complexes, the efficient use of energy makes a much greater difference than in a family home. In addition to lighting, there is potential for applications and savings in a wide range of building areas – from heating and cooling to shade and ventilation. With intelligent sensor technology, for example, the heating switches off automatically as soon as a window is opened, or blinds lower automatically when a certain amount of sunlight is detected. The issue becomes even more important for large commercial complexes, where up to 100,000 sensors are installed in some cases. If every one of them eventually had to have its battery replaced, it would require a tremendous amount of resources. Building automation makes it possible to interconnect all the components of a building and improve its carbon footprint. This involves adjusting the heating based on the weather forecast, for instance. The expansion of electricity infrastructure through the installation of smart meters, which intelligently measure electricity consumption and report it to the grid operators, is also currently on the agenda. This will make it possible to optimize energy management based on precise consumption data.

Experts agree that the increased use of building automation is an important driver of the energy transition. Nevertheless, much remains to be done. According to Severin Beucker, one of the things hampering progress in this field is the lack of clarity regarding related responsibilities. Germany is still a country with a large number of rental apartments. Take heat, for instance: “The costs of investing in building automation need to be divided fairly between landlords and tenants,” Beucker asserts, explaining that improvements that require an initial outlay will significantly reduce utility costs over the long term. Moreover, building automation has long been more of a topic for niche enthusiasts. “The luxury segment will probably continue to be the main driving force behind these innovations,” says Michael Schuster from Enertex. Still, he believes bringing building automation to the masses has to be the goal. For Matthias Kassner, things are moving towards the retrofitting of existing buildings. “There’s a massive trend towards quick and easy-to-install solutions that don‘t require specialists,” he reports. This is where wireless solutions really come into their own.

As building automation continues to advance, nothing will stand in the way of increasing efficiency and sustainability in the energy-hungry building sector. Or, as Borderstep founder Severin Beucker puts it: “There’s a great deal of potential just waiting to be tapped.”

Julian Hörndlein is a freelance technology journalist in Nuremberg.