Unica Makes Simulation the Foundation for Well-Informed HVAC Decisions with Hysopt

At technical services provider Unica, designing and decarbonising HVAC installations involves much more than simply selecting the right components. Particularly in complex systems involving heat pumps, thermal energy storage and multiple energy sources, it is essential to understand how all the components interact and what performance the installation will ultimately deliver.

‍

For Gerolt Feikens, Hysopt has become an important part of his daily work over the past few years. He uses the software for a wide range of applications, from designing new installations to analysing existing systems that are not performing as expected.

‍

What makes the biggest difference for him is the ability not only to calculate technical design choices, but also to visualise and demonstrate their impact. This is changing not just how installations are designed, but also how Unica communicates with clients and technical partners.

Complex HVAC installations bring together multiple disciplines. Hydraulics, control strategies and energy performance continuously influence one another. Traditionally, these aspects are documented through technical schematics, calculations and functional descriptions.

‍

Although these documents are essential, they do not always make it easy to understand the behaviour of an entire system or clearly explain design decisions to clients.

‍

With Hysopt, Gerolt can bring these different aspects together in a single model. This allows him not only to design an installation, but also to simulate how it behaves under different operating conditions.

‍

He particularly values the ability to demonstrate system performance before installation. “This is the ideal design. This is the simulation. It demonstrates that the system works. Now build it this way,” he explains when describing how he presents the results to technical partners.

‍

The model therefore provides a well-founded starting point for further engineering and implementation. It also offers advantages during commissioning. When questions arise about system behaviour or control strategies, the parties involved can refer back to the original design assumptions and simulation results.

‍

For Gerolt, this represents an important shift: design decisions are not only documented, but also supported by a model that demonstrates why a particular solution works.

A significant part of Gerolt's work involves advising clients who want to decarbonise their existing installations.

‍

Often, the process begins with a relatively straightforward question. A client might want to replace their boilers, reduce natural gas consumption or investigate whether heat pumps would be a suitable solution. However, behind that ambition lie numerous technical and energy-related questions.

‍

“A client comes to us with a building and an ambition. They might want to become almost entirely gas-free, for example, but they don't yet know exactly how,” Gerolt explains.

‍

To provide well-founded advice, Gerolt first examines the building's energy demand and potential installation concepts. Once a direction has been chosen, he develops the design further in Hysopt.

‍

There, he can model and simulate the entire system, including its hydraulic configuration, control strategy and interactions between different components. This helps establish whether the proposed concept will function technically and what energy performance can be expected.

‍

The simulation results then provide an important basis for assessing the electrical feasibility of the concept. This is particularly relevant in the Netherlands, where grid congestion is becoming an increasingly significant challenge in decarbonisation projects.

‍

Thanks to this approach, Unica can not only give clients insight into potential natural gas savings, but also demonstrate whether a proposed solution fits within the available electrical capacity.

‍

And when a particular ambition proves unfeasible, Gerolt can clearly demonstrate why. Rather than simply stating that a solution is not possible, he can use simulation results to show where the limitations lie.

‍

This makes the advice more concrete and helps clients make realistic, well-informed investment decisions.

Beyond the technical benefits, Gerolt also sees considerable potential in how Hysopt can connect different disciplines and project phases.

‍

Within Unica, the software is already being used for a wide range of applications, from engineering and energy simulations to troubleshooting and analysing installations that consume more energy than expected.

‍

Gerolt sees particular opportunities in an approach where different teams work from the same model. Engineers can focus on the design, while other specialists further develop the simulations, control strategies or energy performance assessments.

‍

“You can use Hysopt for everything. For communication, for design, but also to look back at an installation that has already been built and investigate what is actually happening,” he explains.

‍

This versatility makes Hysopt particularly valuable to him. He also uses the schematic diagrams generated from the model as a basis for functional descriptions and discussions with control engineering partners. This ensures that the intended operation of the installation is clearly documented from the outset.

‍

Ultimately, Gerolt sees Hysopt as a way to better align the entire process, from the initial client enquiry and design through to implementation and the analysis of existing installations.

‍

For clients, this primarily means greater clarity. Instead of receiving only technical schematics and calculations, they gain a visual, well-substantiated understanding of their future installation, including its expected operation, energy performance and potential limitations.

‍

As Gerolt himself summarises, “It helps me enormously in my advisory work.” And that is precisely where he sees the greatest value of Hysopt: translating complex technical challenges into solutions that are not only well designed, but whose performance can also be demonstrated and explained.