The aim of the symposium “Future-proof technical building management with BACnet - the digital twin of building automation (BACtwin)” on June 21, 2022 was to find out what it takes to use BACnet in larger real estate portfolios in a manufacturer-neutral way so that they can be managed in an energy- and cost-efficient manner. A number of prominent figures from the building automation scene as well as some operators of large real estate portfolios and building automation planners traveled to the Gutenberg Digital Hub in Mainz to gain a holistic understanding of the topic. The event was hosted by ICONAG-Leittechnik GmbH with the support of the other sponsors GEZE GmbH and Somfy.

Need for further BACnet specifications

For future-proof and digitalizable technical building management, it is not enough to simply prescribe the BACnet standard in accordance with AMEV or other regulations. Anyone who wants to manage several buildings with BMS systems from different manufacturers from a central location has probably learned this by now.

In his keynote speech at the conference, BACman Hans Kranz impressively explains why this is the case: when the BACnet world standard ISO 16484 was formulated between 1995-2005, the so-called bus war was raging. The lowest common denominator had to be found between Profibus, FND, LON, EIB/KNX and BACnet. And this did not include the forward-looking BACnet objects and properties. This created a standardization gap. As the building owners and their planners do not specify the use of BACnet objects and their properties in accordance with the applicable standard, the market cleverly uses this to tie the building owner to the first supplier for extensions under the guise of BACnet. This means that the idea of the building owner being independent of the brand and manufacturer is now a thing of the past.

This standardization gap is still the cause of media disruptions between client specifications, planning output, engineering and operation of BA systems, explained Prof. Dr. Rupert Fritzenwallner from the Austrian Armed Forces (ÖBH). Together with Hans Kranz, he is the author of the highly acclaimed reference book “The digital twin of building automation with BACnet”. In this book, the two experts describe, among other things, how the proven tool of the BACnet function list in BACnet planning can be expanded to include the client's specifications and the installer's specifications in order to achieve BACtwin (see article in BACnet Europe Journal 32 03/20). The ÖBH has now been successfully using BACtwin for 4 years, in particular to achieve the goals of the EU Commission's Green Deal, the targeted circular economy and climate-neutral building management.  Prof. Dr. Fritzenwallner also highlighted the further potential offered by the use of the Internet of Things and Long Range Wide Area Network (LoRaWAN) in conjunction with the BACtwin.

Prerequisites for the successful use of BACnet in real estate portfolios

In order for BACtwin to be used successfully by building owners and operators of their own and larger real estate portfolios, a number of prerequisites must be met. One of these is the interpretability of data, as Christian Wild, founder and managing director of ICONAG-Leittechnik, explained in his welcome address. Without interpretable data, there can be no digitalization, e.g. through the use of artificial intelligence (AI), as the diagram of the stairway to AI illustrates (see Fig. 1).

The key element of the BACtwin data model is therefore the user addressing system (BAS), often also referred to as the labeling system. Jürgen Hardkop (Chairman of AMEV-AK BACtwin) and André Höhne (member of the aforementioned working group) came to this conclusion. As existing BAS are not optimized for BACtwin and are not machine-readable, the AMEV-AK BACtwin has developed a new, powerful BACtwin-BAS (E) in continuation of VDI 3814 and presented it for the first time at the conference. This is machine-readable, user-friendly and future-proof. With the help of the BACtwin-BAS, machines can recognize and clearly interpret the data content. Test tools can validate the mass data 1:1 for planning, execution and operation. IT-based data exchange enables simple, fast and error-free handling in GA projects.

A building owner can only achieve future security without dependence on a specific brand or manufacturer if he demands BACtwin. To achieve this, BAS and the BACnet profiles and object templates for the planned units, assemblies and systems for room and system automation must be defined and enforced via a BACnet specification sheet during tendering and awarding, explained Daniel Rörich, who is responsible for BACnet consulting for building owners at ICONAG.

A simple and very efficient BACtwin test procedure was presented by GA data pioneer Bernhard Ramroth from Excel-for-you. With his Excel-based testing tool, he showed how it is very easy to check during implementation and acceptance whether all automation stations have been set up in accordance with the BACtwin specifications, regardless of make and manufacturer. This also puts a stop to the use of proprietary or even hidden properties.

Clear advantages for operations and management thanks to BACtwin

Even if the formulation of the BACtwin specifications means a certain amount of planning work and the manufacturers of proprietary solutions will certainly not be jubilant, the advantages for the building owner are relatively clear. Christian Wild from ICONAG-Leittechnik showed how great the savings in engineering costs are on the part of the management and operating device if it reads the BACnet automation stations and can recognize which system is involved on the basis of the data and displays the appropriate, standardized system images and carries out alarm and timer configurations largely automatically - and this completely independently of the control brand used.

Thomas Bender from pit-cup explained how building automation can be connected to the BIM model on the basis of BACtwin. With CAFM Connect, the CAFM Ring has created such a standard. This allows the BIM profiles of systems and components to be mapped as an IFC data record in IT systems, such as in the management and operating system or in the CAFM system. Technical building management processes, e.g. for maintenance, repair or energy management, can thus be implemented digitally between the different system worlds without the need for consultation.

Jürgen Keller from GEZE GmbH clearly demonstrated the opportunities and benefits that arise from the integration of “ancillary systems” such as window or door control. The door or window system must, for example, provide data and functions for building automation, as well as fire and burglar alarm systems and access control. Here too, BACtwin offers an optimal basis for standardization.

There are also significant advantages for shading. Dirk Mommaerts from Somfy explained that this is particularly important for increasing user acceptance of the increasingly complex automation requirements. When using functions such as complex automatic wind monitoring, shade management and sun position tracking to optimize energy consumption and increase comfort, maximum transparency for the user and a seamless connection to the building automation system are essential in large projects. The hurdles for both are significantly reduced by the BACtwin.

Prof. Dr. Rupert Fritzenwallner, as an experienced building owner, concludes with an urgent appeal to the building owners present: Demand interoperable solutions for the automation stations (AS) and the management and operating equipment (MBE) and do not allow yourself to be convinced by superficial arguments of proprietary approaches.

The Gutenberg Digital Hub e. V. is a broad alliance of business, science, and politics that is working together to meet the challenges of digital transformation. It is based in the old wine warehouse at the customs port in Mainz. Networking and exchange have been lived here since 2019. The spacious premises between the Rhine and the harbor basin offer room for meetings and events. A culture of exchange and learning from and with each other is to be lived here with the aim of making digitization in companies, the city and the region fit for the future.