Digitalization of Heavy-Duty Controls Revolutionizes District Heating Systems

Introduction?

The digital transformation is reshaping industries worldwide, including the district heating sector. District heating networks, which traditionally relied on mechanical components, are now embracing digital solutions to enhance efficiency and performance. Danfoss, a leader in this field, has been at the forefront of developing advanced self-acting flow and differential pressure controllers, essential components for district heating systems. The advent of digitalized versions of these controllers presents exciting new possibilities for optimizing network operations and reducing costs.?

The challenge of pressure fluctuations?

District heating systems face several challenges, particularly in maintaining optimal pressure and balanced flow conditions. Traditional mechanical controllers, while reliable, have limitations in precision and adaptability in peak and off-peak demand. Issues such as flow and temperature oscillations are affecting hydronic balancing and causing inefficiency of pumping systems. These problems can lead to energy waste, increased wear and tear on equipment and inconsistent heat supply to end users causing them discomfort.?

Digital empowered dynamic hydronic balancing?

Danfoss' Virtus heavy-duty differential pressure and flow controllers offer intelligent solutions to eliminate the pressure and corresponding flow variations. These self-acting controllers significantly increase the performance and efficiency of the system as they establish better control performance and lower return temperatures.??

Besides the traditionally well-known pressure and flow controllers, Virtus also provides more advanced pressure independent control valves, where the regular motorized control valve and pressure/flow controller are combined into one product.?

What is special about these solutions is the fact they can be equipped with advanced electrical actuators, allowing for remote and autonomous adjustments of differential pressure settings and flow balancing for all demands. This digital upgrade enables continuous real-time optimization of the district heating network, reducing heat transfer losses.?

In particular the AFQMP 2 pressure independent control valve offers a revolutionary new solution. Equipped with an extra spring and an AMEi 6 actuator, it allows adjusted differential pressure setting between 0.1 and 1.0 bar for adaptations to different heat demands. By that it offers more precise and lower flows, as well as higher capacities and bigger flows compared to traditional solutions.?

One notable feature of the AMEi 6 is the iSET functionality, which autonomously adjusts differential pressure to prevent flow and temperature oscillations. By monitoring the motorized control valve’s modulating control or feedback signal, it responds to oscillatory behavior. This ensures the valve operates within its high-authority range, stabilizing the control loop and improving overall system performance of a substation.?

Another significant innovation is the AMEi 6 with iNET functionality, which allows remote network balancing function and differential pressure adjustments at a single branch level and critical network points. This is the solution for constantly changing heat consumption which requires corresponding changes in the heat distribution. The remote balancing function significantly optimizes the hydronic conditions of the network, ensuring that pumping stations operate at the minimum required pressure. This reduces pumping costs and improves the stability and efficiency of the district heating network.?

Benefits?

The benefits of these, optionally digitalized, controllers are manifold:?

1. Energy Efficiency: Optimized pressure and flow control minimize energy wastage, leading to lower operational costs.?
2. Improved Supply Quality: Stable pressure and flow conditions ensure a consistent and reliable supply to end users, enhancing their satisfaction.?
3. Cost Savings: Reduced pumping costs and lower maintenance needs translate into significant financial savings for district heating operators.?
4. Enhanced Equipment Lifespan: By eliminating oscillations and ensuring stable operation, the wear and tear on system components is significantly reduced.?

Case Study: Giessen Network?

A practical example of these benefits can be seen in the Giessen district heating network located in Germany. The Stadtwerke Giessen utility, located close to the city of Frankfurt, faced frequent customer complaints about inconsistent hot water temperatures. Traditional methods, including the installation of an extra oil boiler, failed to resolve the underlying issues, and only added to the energy costs.?

The introduction of Danfoss' Virtus valve combined with the intelligent iSET function of the AMEi 6 actuator revolutionized the network's performance. By installing the SCADA tool ECL Portal (which since then has been further improved and renamed into Leanheat? Monitor), operators quickly identified and diagnosed continuous flow and temperature oscillations. The iSET function was able to detect these oscillations and adjust the differential pressure in real time, stabilizing the system within just 20 minutes of installation. This led to a significant reduction in energy consumption and the elimination of the extra boiler, achieving a return on investment (ROI) within weeks.?

The bigger picture of digitalization?

Digitalization in district heating is about more than just connecting devices to the internet. It involves using advanced software, sensors, real-time data processing, and smart algorithms to help these devices work together and optimize the entire system. For example, Danfoss Leanheat? is an application-driven suite of end-to-end software solutions and services that harness the power of digitalization. It enables optimized energy production and consumption, increase operational efficiencies, and put building control and maintenance right on screen.?

As result of this transformation, digitalized district heating systems offer real-time insights and adjustments to ensure optimal operation. This means more efficient energy use, lower costs, and a more reliable heating supply for users.?

Conclusion?

The digitalization of self-acting flow and pressure controllers marks a significant milestone in the evolution of district heating systems. By leveraging advanced technologies, these intelligent controllers offer unprecedented opportunities for optimization and efficiency. Danfoss' innovations in this field not only address current challenges but also pave the way for a smarter, more sustainable future in district heating.?

Incorporating these digital solutions will help district heating operators achieve their goals of reducing pumping costs and differential temperature, plus enhancing overall system performance. As the industry continues to embrace digitalization, the benefits will become increasingly evident, making a compelling case for widespread adoption of these advanced technologies.?

More information?

Find out more about Danfoss Virtus heavy-duty pressure and flow controllers in the new eBook document.??

You can find it right here:?https://bit.ly/3Yghz3K

If you want to learn more about the case at Stadtwerke Giessen utility, you can read the entire case story right here:?https://bit.ly/3YlWyo2

And if you want to read more about the digital solutions and services within Danfoss Leanheat? software suite, find it right here: https://bit.ly/4dbySXY