#projektVukovar - sustavno gospodarenje energijom u višestambenim zgradama

Energy Management in Multi-Apartment Buildings

416 measuring devices, 1000+ measurements every 15 minutes in Vukovar

Marko Habazin, Project Manager at Emasys d.o.o.

Marko Habazin, Project Manager at Emasys d.o.o., talked about the latest project of the Agency for Legal Transfer and Real Estate Brokerage (APN) and about our IoT solution for collecting data on energy and water consumption and air quality. He highlighted the biggest challenges of the project, but also the successful solutions that were implemented.

Establishment of Systematic Energy Management and Development of a New Financing Model

The procurement tender for the pilot area of the City of Vukovar was the first of six public tenders as part of APN’s pilot project. The project is called “Establishment and Implementation of Systematic Energy Management and Development of a New Financing Model”. Can you tell us about the project in more detail?

As part of the National Recovery and Resilience Plan (NRPO), APN has launched an ambitious and commendable pilot project that lays the groundwork for sustainable energy and water management in multi-residential buildings. The aim of this innovative project is to implement systematic energy and water management in multi-apartment buildings, providing users with an insight into their consumption in real time through the national Information System for Energy Management (ISGE). In addition, the project enables the monitoring of indoor climate conditions, comfort and air quality, thus ensuring a healthier and more energy efficient environment for tenants.

This project includes 64 pilot buildings located in six selected cities across Croatia, including Vukovar, Zagreb, Velika Gorica, Karlovac, Rijeka and Split. Each of these cities plays a key role in testing and applying the new energy management model.

Can you give us some more information about the specifics of the tender?

Our task in the City of Vukovar was to equip 8 multi-residential buildings with a automatic meter reading (AMR) system for the purpose of collecting data on electricity consumption (including demand), thermal energy consumption for heating and hot water, as well as cold water consumption. Likewise, the task was to measure and collect data on the indoor climate conditions in the apartments (air temperature, relative humidity and carbon dioxide concentration). The project requires the delivery of data to the National Information System for Energy Management (ISGE) at fifteen-minute intervals over a period of two years.

Project in numbers - 419 metering points

Specific technical challenges

As the only participant in the first call to tender, Emasys was the first to plan, offer and implement a technical solution and, one might say, raised the bar quite high for prospective applicants. Were there specific requirements that influenced your solution?

Emasys has been implementing AMR systems for a long time and is continuously looking for new ideas and solutions. In parallel, we are constantly developing our data management software. Back in 2021, we were already looking for reliable devices for measuring indoor air quality because we recognized the importance of monitoring air quality as a direct consequence of the Covid-19 pandemic. We then prepared our cloud-based software for the reception and display of indoor climate and air quality data.

However, there is simply no universal solution for automatic metering projects. The tender requirements, characteristics of the locality, location of the metering points, any existing infrastructure and the interests of the other involved parties are all factors that influence the solution.

  1. The first challenge was provided by an existing AMR system. More pecisely, Tehnostan is a company for the production, distribution and supply of thermal energy in the city of Vukovar, and the existing system, consisting of metering points for hot water and heat consumption (calorimeters) in buildings, is used for monitoring and billing purposes. For the purposes of the project, we had to ensure the parallel operation of both systems; the uninterrupted operation of the existing system, as well as our newly-installed one.
  2. Another challenge we faced was the integration of several different communication protocols into one compact and functional unit. Since the existing network is based on the M-Bus and wireless M-Bus protocols, we planned to integrate M-Bus and wireless M-Bus, Modbus TCP/IP (due to the project’s requirements for measuring apparent used power) and the LoRaWAN communication protocol. In order to enable “connectivity” for LoRaWAN communication in the City of Vukovar for this and other future projects, we established a LoRaWAN IoT network.
  3. The third challenge was actually a tender requirement: continuous reading and delivery of all requested data to ISGE at a minimum frequency of every fifteen minutes over a period of two years. In addition, APN, the client, defined that the accuracy of the measuring equipment and delivered data as well as the regularity of data delivery will be checked during the contracted 24 months.

Innovation comes first

So what did your technical AMR solution look like?

It’s easier to explain the solution using a standard scheme.

Metering solution for energy management in Vukovar

We installed 14 electricity meters with Modbus TCP/IP communication modules that also offer electricity demand measurement (as per the project’s requirement). In the same electrical cabinet, we installed a data concentrator capable of receiving data via M-Bus, wireless M-Bus, and Modbus protocols.

This data concentrator also provided a solution to integrate our system with Tehnostan’s existing M-Bus and wireless M-Bus network. Specifically, the concentrator offers the possibility of using two ‘masters’ within the same M-Bus network. It is installed between the existing master and the metering points, responsible for reading and transmitting data. This way, the existing Tehnostan M-bus master can operate seamlessly, receiving data from the ‘slave’ interface of the data concentrator.

As the existing AMR system from Tehnostan did not cover hot and cold water meters in the apartments, we expanded their existing system (as per the project’s requirement) by installing new billing water meters and replacing existing water meters that could not connect to a smart metering system. This allowed us to collect measurements from heat meters, hot and cold water meters, and electricity meters connected to the existing M-Bus network.

Unlike the individual apartment water meters, we connected the main billing water meters (for the total consumption of the building) to automatic meter reading devices using the LoRaWAN protocol.

The LoRaWAN protocol also hosts 46 indoor air quality sensors that we installed in 5-6 characteristic apartments in each multi-residential building. As an addition to the project, apart from the requested parameters for indoor comfort (temperature, rh, and CO2) sent in fifteen-minute intervals, we also transmit air pressure and volatile organic compounds (TVOC) concentration data.

Finally, the data concentrators and LoraWAN gateways send the automatically-collected data to our cloud application – AMR Emasys for energy, water and air quality management, which are then processed and forwarded to the APN’s Information System for Energy Management (ISGE).

Joint effort

How do you feel about the completed project? Is there anyone you would like to thank?

The feeling is really great. It was an intense journey full of challenges, but now that the first part of the project has been successfully concluded (installation and commissioning), I feel really proud of the way we planned and executed the works, keeping in mind the need to satisfy the second part of the tender, i.e. continuous delivery data with minimal system maintenance.

Of course, we could not have achieved this success without the support of everyone involved. Therefore, I would like to thank:

  • our suppliers for the timely delivery of equipment, but also their customer support
  • Vodovod grada Vukovara (Vukovar’s water utility)
  • HEP Vinkovci (electricity utility)
  • one big thank you to Tehnostan for their selfless effort, commitment and understanding of all involved employees
  • and of course to the Client APN for the commendable project.



We implement customized advanced metering solutions in order to reduce energy and water consumption for higher operational efficiency and business competitiveness and for a greener future.