Innovation to the rescue
Years of expansion at the Ludmillenstift Hospital resulted in an HVAC system that just could not cope. The introduction of Belimo Energy Valves™ significantly reduced the water flow rate of the heating network, resulting in smart, transparent, and energy-efficient load-dependent heating and cooling systems – while improving comfort and keeping energy consumption stable.
The Ludmillenstift Hospital is located in the city of Meppen in Lower Saxony (Germany). This large multi-discipline hospital forms the main pillar of a comprehensive health network and can boast more than 160 years of providing healthcare to the Emsland region. It prides itself on exceptional levels of care for its patients, backed by modern infrastructure and state-of-the-art medical technology, including advanced diagnostic and therapeutic expertise and other specialised services.
|Institution: Ludmillenstift Hospital||Inpatients: 20 000 per year|
|Location: Meppen (Germany)||Outpatients: 150 000 per year|
|Opened: 1851||Beds: 420|
Cold rooms and bold attempts
Technology also plays a crucial role in ensuring the functionality, comfort, safety and efficiency of the buildings that make up the hospital’s infrastructure. However, patient demand and specialist facilities have grown beyond capacity over the years, and repeated expansion and renovation programs have resulted in major challenges related to controlling and maintaining the hydronic distribution system.
Maintaining a well-balanced HVAC system can be challenging in multiple-building complexes like hospitals. This was certainly the case when the situation came to a head, with many complaints from staff about cold rooms and zones in the winter months. The facilities management team at the Ludmillenstift was aware that certain parts of the site were regularly undersupplied with adequate hot water and recognised that the heating system’s hydronics was struggling to manage and monitor comfort levels.
The team made bold attempts to improve the situation by dramatically raising the boiler temperature, with all pumps set to full load. However, this met with very limited success; the complaints continued and the excessive pumping and generation of additional steam energy led to a huge increase in cost, which heavily stretched the hospital’s budget. At this point, the Ludmillenstift decided to call in experts – in the form of the company G.U.T. August Brötje KG – to find out the root cause of the issue and decide on an adequate solution.
Oscillating heat supply
The engineers from August Brötje KG looked over pre-existing system drawings of the heating supply and decided that only central balancing of the sub-manifolds would solve the hydronic problems. They then carried out an extensive survey of the building’s HVAC system, which disclosed various weaknesses and bottlenecks. For example, the temperatures measured at the hydronic switch were 90/86°C (194/187°F), and the heat supply of the individual substations was oscillating, which made the heat supply come and go randomly. The lack of hot water reaching the heating coils also repeatedly triggered the frost protection system to shut down the ventilation system in winter, which was especially problematic in the operating theatres. Overall, the heating supply simply had not been modernised at the same rate as the rest of the hospital.
To address the enormously high boiler flow and system return temperatures throughout the year, Peter Meier, controls expert
at August Brötje KG, had to define the long-term scope of the improvement project, which included the following specifications:
– All heating manifolds should be adjusted to their nominal flow volume to ensure that only the exact amount of water needed for hydronic balancing is supplied;
– The currently required thermal energy should be recorded and quantified at the respective distribution feeds;
– The system’s return temperature should be reduced to improve the energy conversion efficiency of heat recovery towards the boiler (and prepare for the later
planned use of a combined heat and power unit);
– The flow volume through the entire facility should be load-dependent to make sure that the system can be operated efficiently, and that the maximum amount of water is not permanently pumped through the buildings.
Maintaining comfort and efficiency
Belimo had already introduced Peter Meier to its latest innovation – the Belimo Energy Valve™ – and this seemed the ideal solution for the Ludmillenstift Hospital site. This electronic, characterised control valve combines pressure-independent control, flow and energy measurement, automatic hydronic balancing and data monitoring, all in one device. By continuously measuring water flow and temperature of the supply and return (delta T), the Belimo Energy Valve™ determines the thermal energy being consumed. The automatic flow control function then makes sure that only the required amount of energy is supplied, regardless of any differential pressure fluctuations.
The Belimo Energy Valves™ were put to the test from February to March and proved a complete success in the prevailing weather conditions of temperatures as low as -12°C (10°F). They dynamically controlled and monitored all hydronic manifold circuits by continuously measuring the flow and water temperatures, from the very first moment they were commissioned – problems with the heating supply had finally been localised and solved. From then on, all rooms and zones connected to manifold circuit 1 were supplied with precisely the right volume and correct flow of water actually needed for heating purposes, which considerably reduced the amount of water the hospital had to supply. The data the Belimo Energy Valves™ measured and recorded also provided an in-depth view of what was really happening in the system, leading to recommendations for further potential improvements for energy efficiency.
The energy reports automatically generated from the Belimo Energy Valves™ are much appreciated by the Ludmillenstift because they provide a transparent view of the flow, temperature and overall coil performance. As an additional benefit, the hospital now uses the data from the hot water preparation for regulatory reporting to the health authority.
The Ludmillenstift Hospital maintained comfort and energy consumption in 2020 at 2013/2014-levels despite having expanded floor space by 40 percent in the meantime.
The successful completion, informative results and data transparency of the test phase showed that the Belimo Energy Valves™ would be a perfect fit for the complete HVAC system in the hospital, including other application areas where thermal energy and volumetric flow had to be monitored and recorded.
Combine energy measure and control, certified thermal energy measurement and billing
The Belimo Energy Valve™ integrates energy metering, control, delta T management, and if required IoT-enabled billing in one device. It offers seamless and direct integration to the BMS or to IoT-based monitoring platforms, with IoT-based monitoring, performance improvement tools, and billing data. The two worlds of "energy control" and "certified thermal energy measurement and billing" are being united. Bringing together performance features to save you time and money.
Awarded the Solar Impulse Efficient Solution Label
The Solar Impulse Foundation granted a portfolio of 1000 innovative solutions that meet high standards of both sustainability and profitability. We are proud to announce that the Belimo Energy Valve™ has been selected to be one of the 1000 solutions awarded the Solar Impulse Efficient Solution Label.
Step-by-step to set up the Belimo Energy Valve™
The Belimo Energy Valve™ can be configured in different ways. Follow this step-by-step series of videos to learn how to set up the Energy Valve using the information you have available. These interactive videos feature a decision support tool covering all setup and configuration options while dealing with possible unknowns such as the design flow rate or the required minimum delta T.
Modular design for a fast meter exchange
The Energy Valves thermal energy meter consists of a sensor module, connected temperature sensors, and houses metering and logic functionalities. Data communication capabilities via Bus and NFC. The sensor module is available as a spare part. Certain countries require periodic replacement for recalibration according to national regulations. The logic module can be disconnected from the sensor module (leaving all cables connected), enabling the lower sensor module to be easily exchanged.