Armin Anders, co-founder & VP business development, EnOcean asks when is a building truly sustainable?

The unbridled CO2 emissions and the current energy crisis make the urgent need for action clear: we need to save energy! Buildings play a central role in this. 99% of buildings are existing buildings, and a complete energy renovation is not economically feasible. For alternative sustainable measures to be viable, social acceptance and economic benefit must also be present alongside energy savings. In other words, the entire value chain must benefit from sustainability measures, otherwise, these alternative solutions will not lead to the desired outcome.

Sustainable buildings through digital data collection

The solution for sustainable buildings lies in automating them digitally using flexible and maintenance-free sensors that send real-time data to IoT systems. The information is then used to determine the exact need for space and equipment and to intelligently control trades or services. A digital building thus fulfills three important sustainability aspects:

  • Ecology: The environment and its valuable resources should be preserved for future generations. Digitized automation enables efficient use of energy and a significantly reduced CO2 balance. In addition, the use of environmentally friendly materials can be increased, and the consumption of limited resources such as copper reduced.
  • Economy: Sustainable building operation should be economical and provide a permanent, sustainable basis for earning and prosperity. Automation should be flexible and able to adapt to the individual needs of the building. It is also important to be able to retrofit additional features that take into account changing needs or new legal regulations. This leads to attractive overall operating costs, which include investment and operating costs, conversion measures, and disposal.
  • Social aspects: The human factor is crucial in digitization. In terms of social sustainability, all members of a community should have the opportunity to participate in a pleasant work or living environment. The individual needs of users, their health, and work productivity are the focus.

The possibilities and advantages of digitization for sustainable energy saving are significant, especially in the building sector. Radio-controlled sensor technology provides the basis for this in both existing and new buildings. Sensors record the required raw data and transmit it to a cloud for storage, processing, and evaluation. This can be done either classically via gateways or recently also via Wi-Fi access points, which eliminates the need for additional gateways. The special advantage of radio sensors is that they can be flexibly placed at various measuring points, on furniture or objects such as desks, printers, etc. This provides them with precise information for efficient evaluation, so building operators can have a 360-degree real-time view of the building and its usage, as well as its history, through suitable applications and dashboards.

Why wired sensors are a no-go

Wired sensors are expensive and anything but sustainable. With wiring costs of over 100 euros per sensor, the typical acquisition costs triple. In addition, wired solutions are inflexible, as rewiring costs and time are incurred for every renovation. For this reason, truly sustainable applications rely on radio sensors, as costs and benefits are in the right proportion. Radio sensors provide the required data from numerous points in the building as a technical basis.

Where do radio sensors get their energy?

Although radio sensors offer many advantages, they also have a major disadvantage: the power supply via batteries. These are usually changed annually by professional service providers to avoid early failures, resulting in high ongoing maintenance costs. After just two years, the sensor price typically more than doubles. The huge amount of battery waste also becomes a problem. For this reason, self-powered and batteryless radio sensors have now established themselves as maintenance-free and sustainable alternatives.

Battery-free wireless sensors use the energy available in their environment. Movement, light or temperature differences can serve as a power source without the need for a battery change. This makes them environmentally friendly and reliable. They can also be freely placed and expanded at any time. They enable the digitization of buildings with thousands of data points and can provide the required information for comprehensive, flexible and demand-dependent control from any location. Thus, battery-free wireless sensors are a basic requirement for a sustainable IoT solution.

Digital technologies are revolutionizing building operation and management

Building data collection through digital technologies enables operators to monitor technical systems in real time and quickly perform necessary work. In the field of housing, more and more companies are using digital functions for both renovation projects and new construction. For example, wireless sensors can report required maintenance and repair work on elevators, heating and air conditioning systems, or other technical systems. Digital door access or doorbell displays are also possible. The sensor data is transmitted to the service provider's system via an IoT gateway or Wi-Fi access points. This enables a more service-oriented, efficient and energy-saving management of the building.

More sustainability with desk sharing

There is currently a very high effectiveness of a digital building in office complexes. With the shift to more remote work over the past years, the use of space in office areas has changed significantly – much fewer on-site employees face an equally large office space. In the concept of desk sharing, several employees share a workspace or desk. There is no longer a fixed workspace or office concept, but each employee chooses a free workspace according to their needs. The workstations can be networked with modern technologies such as laptops and smartphones, so that users can work flexibly and be mobile. Companies use desk sharing to save costs and to create a more flexible work environment that better meets the needs of employees. This is also a suitable solution for spatial restrictions.

Some impressive figures that make desk sharing in connection with sustainability so promising:

  • Environment: Up to 44% energy savings through the combination of desk sharing (25%) and smart heating (26% for the remaining three-quarters of the area)
  • Economy: €2.4 million cost savings per year through desk sharing for 1,000 employees (€8,140 operating costs per workstation on average in Europe according to the office cost report from, 30% of desks saved according to
  • Social: 5% increase in employee productivity through consistent good air quality and contemporary work models

User acceptance for desk sharing

Often, companies want to implement desk sharing quite simply with Excel, Outlook or QR codes. In such a scenario, an employee scans the QR code on the selected table with their phone and thus sends the information that the workspace is taken. But what if the battery is dead, the employee forgets to scan, they do not want to log in personally to protect their privacy, or they simply lose interest after a certain initial euphoria?

With such a partially manual solution, user behavior is simply forgotten because the necessary data for actual table occupancy is not automatically provided. Sensors show the image of the actual situation in real time – independent of the individual user, which is essential for automation and privacy protection. Both, in turn, are the basis for good functionality and operability, and therefore a prerequisite for employees to be happy to use the application based on constantly correct data on availability even after a year, and for the investment to be sustainable.

Interoperability as a sustainability factor

As expected, space management and energy savings are only the beginning of a fully comprehensive smart building in the future. Therefore, it is crucial to pay attention to the modularity and interoperability of the systems and products used.

Examples of the most important sensors and actuators in a smart building:

  • For space management: occupancy sensors for rooms and tables and people counting sensors
  • For health and cleaning: air quality sensors, service call buttons, as well as sensors for space management to determine cleaning needs
  • For further energy savings: temperature sensors, battery-free wireless heating valves, and electrical consumer switches for detecting and switching off standby power consumers
  • For security: window contacts, water sensors, motion sensors, and people counters

Battery-free wireless sensors hit the center of sustainability with all the factors mentioned above and are therefore a crucial cornerstone for sustainable digitization.